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General News

Sorting Salvinia

An aquatic fern native to southern Brazil,giant salvinia (Salvinia molesta) is consid-ered one of the most invasive plants in theworld. Its rapid rate of spread is facilitatedby environmental adaptability coupled withan ability to propagate vegetatively fromplant fragments.

It has been the target of classical biologicalcontrol programmes since the 1960s inAfrica, Asia, and Australia. However, thefirst attempts were unsuccessful in Africa,India, Fiji, and Sri Lanka because of themisidentification of the plant as Salviniaauriculata. Researchers surveyed S. auric-ulata in Guyana and Trinidad and found asmall weevil identified as Cyrtobagoussingularis. Although C. singularis didestablish in several areas, it had no effect onthe infestations. Salvinia molesta wasseparated from S. auriculata in 1972 and itsnative range in Brazil was discovered in1978. In 1980, what was thought to be abiotype of C. singularis from S. molestawas introduced at Lake Moondarra inAustralia and proceeded to destroy morethan 30,000 t of S. molesta in less than oneyear. Closer examination of the 'biotype'resulted in its elevation to species status,namely C. salviniae. This new speciesreversed earlier failures and successfulprogrammes were conducted in Australia,Fiji, Ghana, Kenya, Malaysia, Papua NewGuinea, South Africa, Zambia, Zimbabwe,India, Botswana, Namibia, and Sri Lanka,where control has been dramatic and rapid:in many cases S. molesta was reduced bymore than 90% in less than a year followingrelease of C. salviniae*.

Here we look at progress in twoprogrammes to combat recent invasions.The first, in the USA, underlines how taxo-nomic uncertainties and confusion can stillconfound biocontrol. The second, in theSenegal River in Senegal and Mauritania,deals with management of invasive speciesto mitigate threats to both the environmentand economic development.

*Tipping, P. (2000) Biological controlprogrammes for giant salvinia: history andupdate on US efforts. Water Hyacinth NewsNo. 2, p. 6.

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Salvinia: USA Begins Round Two

Cyrtobagous salviniae was released for thesecond time against giant salvinia (Salviniamolesta) in Texas and Louisiana in October2001. Weevils for this release wereobtained from cooperators in Australiawhere they have been used successfully tocontrol Salvinia molesta. Following thesecond release in the USA, numerousadults and significant damage were foundat most of the sites 2 months later inDecember. The winter season is expectedto inhibit any further activity by the weevilsbut we hope to learn if they can overwinterat locations in east Texas and westernLouisiana. Additional releases of C.salviniae will be conducted if necessaryduring the spring and summer of 2002.

Salvinia molesta has been established in thewild in the USA since at least 1998, but it ispossible that it has been living free in theUSA for rather longer, as it has been widelydistributed as an ornamental plant and iseasily obtained via the Internet. Firstdiscovered in eastern Texas, it now extendsinto western Louisiana.

The first release of C. salviniae wasconducted in June 1999 using weevilscollected from common salvinia, S.minima, in Florida rather than the tried-and-tested stock from Australia, as thisobviated the risk of introducing newpathogens or parasites into the USA.Cyrtobagous salviniae had been introducedaccidentally into Florida prior to 1960 andis now found throughout the state feedingon S. minima, and has also been foundattacking S. molesta at one site insouthwestern Florida. Unfortunately, theresults of the first biocontrol attempt wereunclear as many of the original Texas andLouisiana release sites were corrupted ordestroyed by floods, droughts, saltwaterintrusion, or landowner actions. Significantdamage of the salvinia was noted at onerelease site, though, before it was destroyedby the landowner (despite a previousagreement not to do so).

Gene sequence studies in early 2000 foundminor differences between 'Australia' and'Florida' weevils in the number of base pairsin the D2 gene. Further releases of the'Florida' weevils were suspended becauseof the taxonomic uncertainty this created,and instead efforts were redirected to

populations of 'Australian' C. salviniae,collected originally from Brazil and used insuccessful biological control programmesin Australia, Papua New Guinea, SouthAfrica, and other countries.

However, the release permit for the'Florida' C. salviniae was not extended tocover the 'Australia' C. salviniae.Regulatory officials in the USDA-APHIS(Animal Plant Health Inspection Service)required that a new permit be issued, whichinvolved a lengthy process made morelengthy when a petition written by anotherlab was rejected because of substandardresearch and reporting, thereby causingfurther delays in obtaining a general releasepermit. In cooperation with Wendy Fornoof Australia (formerly of the Common-wealth Scientific Industrial ResearchOrganisation, CSIRO) and SharonDocherty and Martin Hill from SouthAfrica (formerly of the Plant ProtectionResearch Institute, PPRI), we wrote a newpetition, which was approved and thepermit was finally issued, thus facilitatingthe second releases.

Studies designed to sort out the differencesbetween the populations of C. salviniae arecontinuing. Preliminary data shows that'Florida' weevils are equally attracted toboth S. molesta and S. minima, can repro-duce on S. molesta, and live longer and laymore eggs on S. molesta than on S. minima.In addition, the 'Australia' weevil hasdemonstrated the ability to suppress S.minima in tank studies.

By: P. W. Tipping and T. D. CenterUSDA-ARS Invasive Plant Laboratory,3205 College Ave., Fort Lauderdale, FL33314, USAEmail: [email protected] /[email protected]: +1 954 476 9169

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Salvinia: West Africa Battles Invasives

The freshwater wetland systems ofMauritania and Senegal are crucial habitatsfor Palaearctic migrant birds crossing 200km of the arid western Sahara Desert, andas such they are the focus of national andinternational conservation efforts. A seriesof national parks has been set up by thegovernments of Senegal and Mauritania inrecognition of the importance of the

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ecosystems, many of which are designatedWorld Heritage Sites and/or recognized asWetlands of International Importance byRamsar. The wetlands and the rivers thatfeed them, though, are also fundamental tomaintaining local livelihoods and regionaleconomies, providing fishing, irrigation foragriculture and potable water supplies forboth rural and urban areas. Traditionallymaintained by varying seasonal rainfall,advances in hydrology now create oppor-tunities for water flow to be regulated tomeet needs throughout the year. Suchchanges inevitably lead to disruption of theecosystem, and restoring a balance that issustainable in the long term is proving achallenge, and is having to overcome someunexpected obstacles including invasion byalien water weeds, with Salvinia molesta(giant salvinia) causing alarm mostrecently. Concerted efforts involving local,national, regional and international co-operation have been made to mitigate theSalvinia threat. Mechanical clearanceprovided limited and costly short-termrelief, but improved water management andbiological control through introduction ofthe weevil Cyrtobagous salviniae isproviding a permanent solution. In a widercontext, however, this programme providesa blueprint for both preventing theintroduction of other invasive species, andimplementing good management of thosealready present.

Damming a Problem

Historically, the wetlands were sustainedby natural flooding, but this was variableand in some years of diminished rainfall(particularly since the 1960s) it failed torestore water levels. The erection of dykes,sluices, temporary dams and, morerecently, permanent dams on the SenegalRiver by OMVS (Organisation pour laMise en Valeur du fleuve Sénégal, atrilateral organisation grouping Mali,Senegal and Mauritania) formed the basisof a management plan for the Senegal Riverbasin, intended to allow river navigation,and provide reliable irrigation for agri-culture on hundreds of thousands ofhectares as well as water and electricitysupply for rural and urban areas in Senegaland Mauritania. The Diama Dam, built nearthe mouth of the Senegal River and 25 kmupstream from the city of St Louis, preventsseawater incursion into agricultural land inthe delta during the dry season. Since itbecame operational in 1988 it has wroughtsignificant ecological changes in the lowerSenegal River basin. Upstream, the form-erly estuarine, seasonally dry conditions ofthe lower river have given way topermanent freshwater, and this has led toluxurious development of aquatic vege-

tation, and notably dense stands of Typhaaustralis (reed mace) in shallow water, andmats of floating weeds, initially Pistiastratoites (water lettuce) and now Salvinia.Besides visible impacts on the riparianhuman and wildlife populations there havebeen less-evident effects, including asubstantial increase in malaria, forexample, owing to an increase in year-round standing water for breeding. Down-stream, in contrast, conditions becamemore saline and water supply virtuallyceased during the dry season. Thesechanges were enhanced by embankmentsbuilt to separate the river from thefloodplain, which led to large parts of thefloodplain and estuary becoming drier.

The emergence of an invasive weed threatis thus part of a wider issue: the impact ofchanging land-use patterns and hydro-logical management on the naturalecosystems along the lower Senegal river,where salinity traditionally varied fromnearly fresh (during inundation) to brackishas water levels fell through the dry season.The ecological disturbances above andbelow the Diama Dam are reflected in thenational parks that bound the river to thenorth and south.

Djoudj National Park (Parc National desOiseaux du Djoudj) in Senegal was createdin 1971. It was designated a Wetland ofInternational Importance under the RamsarConvention in 1980 and inscribed on theUNESCO World Heritage List in 1981.This seasonally inundated wetland systemcovers some of 16,000 ha of brackish lakesand pools, linked by a network of channelsstemming from the Senegal River. Djoudjforms a permanent sanctuary for some 1.5million birds, and even more migrants: anestimated three million pass throughbetween September and April, and morethan 70 species of migrant birds wereidentified during an expedition to catch andring Palaearctic birds in 1990. Thesanctuary now lies upstream of the dam.Changes in vegetation since it wascompleted included an initial explosivegrowth of Pistia during the first half of eachdry season, accompanied by a moreinsidious but no less damaging spread ofthe emergent weed Typha.

The Diawling National Park (Parc Nationaldu Diawling) lies on the Mauritanian sideof the Senegal River delta, downstream ofthe Diama Dam in the former estuary. Thearea became completely cut off from freshwater after the Dam’s construction, and forseveral years it was flooded only withseawater. Owing to the high evaporationrate, the area quickly became a salt desert,with high pyrite concentrations in the soil,which also made it unsuitable for

cultivation. OMVS constructed four sluicesto re-flood the area and restore the pre-damhydrological scheme and to preserve therich biodiversity. Since then IUCN (WorldConservation Union) has built two moredykes and sluices to optimize watermanagement, and sponsored artificialflooding by the park management. Inconsequence, 16,000 ha of salt desert arerestored and the ecosystem is reviving, aunique example of the reconstruction of anatural environment. Diawling was made aNational Park in 1991 with a mandate tointegrate conservation and development(including fishing and pastoralism withinits boundaries), and was designated aRamsar site in 1994. It, too, has beeninvaded by Typha, and more recently bySalvinia.

Waves of Invasives

The invasive weed problem surfaced in theDjoudj Park soon after the Diama Dambecame operational in 1988. Reports ofPistia were first received in 1989. Theweed’s encroachment over the next 5 yearswas relentless, covering part of the DjoudjRiver water surfaces within the Park in theearly dry season, making navigationdifficult and threatening the habitat ofpermanent and visiting birds. The fall insalinity following the completion of thedam and inadequate control of flooding(leading to an insufficient drying-outperiod) were cited as being responsible forthis and other changes in vegetation in thePark, and similar changes in the nearbySenegal River and other water bodiesincluding Lac de Guiers. This lake, some50 km upstream of the Diama Dam, is thecity of Dakar’s major drinking water supplyand also provides irrigation water for vastagricultural areas.

Fortunately, there was a good history ofsuccessful biocontrol of Pistia with theNeotropical weevil Neohydronomusaffinis, beginning in Australia andsubsequently elsewhere including Africa.Introductions in Senegal began in Lac deGuiers in 1994, with the support of IITA(International Institute of TropicalAgriculture) and GTZ (Deutsche Gesell-schaft für Technische Zusammenarbeit).Introduction of weevils from Lac de Guiersinto the Djoudj Park took place in 1998 andsubsequent years within the framework ofan EU (European Union) funded researchproject (coordinated by (KoninklijkInstituut voor de Tropen/Royal TropicalInstitute, Netherlands (KIT/RTI) in collab-oration with the Finnish EnvironmentalInstitute, the University of Vienna inAustria and the Senegalese Ministry of theEnvironment). The Pistia vegetationbecame markedly stressed, but as the plants

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die off in the course of the dry season owingto the increased salt content of the water,the natural enemy populations collapse.However, Pistia proved to be a prolific seedproducer (because of – some or all of –increased salinity, crowding and nutrient-rich water owing to bird colonies) andstrong seedling regrowth each seasonmeant the biocontrol agents needed to bereintroduced annually. Releases made im-mediately after inundation at the beginningof the dry season in September proved mosteffective. The introduction of the weevilswas accompanied by improvements inwater management, and together thesemeasures have reduced Pistia populationsto a level that does not impact adversely onthe ecological function of the Park.

While the Pistia problem has been solved,though, Typha is still thriving within thenational parks and outside. In less than 10years, it has built an almost impassable wallbetween the river dykes and the open wateron both sides of the river, clogged shallowwaterways within the parks, invaded theeconomically important Lac de Guiers, andhas caused particular problems by itsspectacular take-over of a shallowfreshwater reservoir just above the DiamaDam. Typha continues to have diversenegative impacts on drinking water,fishing, water-borne diseases and pests,which far outweigh any potential of theplant to combat erosion or be used inmanufacturing.

A new threat, from Salvinia, was firstobserved in the Senegal River near theDjoudj Park in September 1999, the resultof an accidental introduction from a nearbyflooded field where it was undercultivation. By then, though, Salvinia hadalready invaded a stretch of more than 70km of the river between the village ofRosso and the Diama Dam, approximately20 km upstream from the city of St Louis*.It had formed thick mats along the Typhafields, which occur in shallow water alongthe southern shore in Senegal and thenorthern shore in Mauritania. Tributaries ofthe Senegal River as well as narrowchannels through the Typha, which hadbeen kept clear by the local populationusing laborious manual methods, were nowentirely overgrown by Salvinia. Con-sequently, it had become very difficult forthe people in the villages along the river toreach open water and even when they didfishing was impossible because their netsbecame clogged with Salvinia plants. Onlythe main flow of the river was still open.Dense plant masses also piled up againstthe Diama Dam, and these led to it beingopened three times a week to flush downthe Salvinia plants. Ironically, this

unplanned release of water turned out to bevery beneficial downstream of the dam.The remaining mangrove trees, cravingfreshwater during the dry season, staged arecovery. Other beneficiaries were theyoung marine fish that still try to use thisformer estuary as a nursery, and of coursethe local people.

As Salvinia spread through adjacent waterbodies and basins, including the Lac deGuiers, it became increasingly apparentthat this was a new threat, not just to theecological equilibrium, but also to theeconomic stability and human health of theregion. It provided a substrate for otherweeds to encroach on water bodies, andthere was a threat that it could spread intorice fields, as it has elsewhere in the world.The weed also impedes gas exchange, andas the plants decay they consume oxygen,which further disturbs the ecologicalbalance and impacts negatively on aquaticfauna and potable water quality.Conversely, though, weed cover increasesthe available habitat for disease vectorssuch as snails and mosquitoes.

Weevils Win Again

The recognition of the threat from a newinvasive floating waterweed precipitatedprompt action in both Mauritania andSenegal, although fear of nontarget effects,even from the tried-and-tested Salviniabiocontrol agent, led to delays in fundingand of biocontrol implementation inSenegal.

In Mauritania, Salvinia blocked water inletsto the Diawling Park completely, ham-pering the annual artificial flooding.Barriers built in the river in front of thesluices, intended to prevent Salviniaentering the Park, collapsed under theweight of plants as soon as the sluices wereopened during the rainy season inundationin July-August 2000. Worse, the Parkauthorities could not now close the sluicesbecause of the remaining plants. Thuswater continued to leak into the formerfloodplain for 5 months before the sluiceswere repaired and closed. This extendedperiod of freshwater in the Park alsoallowed Typha to establish itself in theareas around the sluices. Salvinia hadserious impact on local people, as fishinghad become impossible and some 40% ofthe fishermen left the area to work in thecity or in the rice fields, thus jeopardizingthe 7 years of ecosystem restoration effortsaimed at promoting re-migration back tothe delta by re-establishing the naturalresources to sustain riparine livelihoods.

The Minister of Rural Development and theEnvironment in Mauritania gave a greenlight to biological control in February 2000.

Donors were slower to react, however.Instead, contributions from the Ministerhimself, the Senator of Rosso, nationalenvironmental NGOs, the fishermen of theDiawling Park, and some DGIS (DutchDevelopment Aid Agency) workers paidfor a shipment of 300 Cyrtobagoussalviniae weevils from PPRI (PlantProtection Research Institute), SouthAfrica in April 2000. Charmed by thisprivate initiative, PPRI charged onlytransportation costs: a mere US$300. Theweevils were used to establish a startercolony in plastic containers (purchased byan Austrian and Dutch developmentworkers) on the shores of the SenegalRiver. Continuing the spirit of ‘do-it-yourself’ biocontrol, local fishermen fromthe village of Zirét Takhredient becameinvolved in rearing and maintaining theinsect cultures, regularly refreshing thebreeding culture with fresh Salvinia plantsand removing dying ones. These peoplenormally fish in the Park, migrating to theriver as the Park dries up. Continuingsupport for Diawling Park staff and thefishermen was provided by a GTZtechnical advisor working at the Ministry ofRural Development. First releases weremade in June 2000 at various sites from theDiama Dam to Rosso, and 9 months laterthe impact was visible within the Typhastands: Salvinia had completelydisappeared. More fishermen are nowbeginning to return.

The only international funding for thisstriking success was from China, whichcontributed to the state budget formechanical removal of Salvinia in front ofthe main water inlets of the Park, just beforethe artificial flooding period in 2000. Thespeed with which control has beenachieved is testament to the dedication ofthose involved, decisive action at everylevel, and the cooperation and generosity ofall involved. Such qualities may not beenough to meet future invasive threats:Salvinia is acknowledged to be an ‘easy’target for biocontrol, and the internationaldonor community needs to be ready to helpMauritania in the future.

Across the river in Senegal, the Djoudj Parkhad remained free of the weed. Sluiceswere kept closed to prevent Salviniaincursion, but clearly this bought onlylimited time. The weed was, in any case,impacting seriously on the livelihoods andhealth of the population outside the Park.The Ministry of the Environment quicklymobilized initiatives. The scientificcommittee (Groupe de Réflexion etd'Appui Scientifique et Technique;GRAST) of the National Parks Directorate(Direction des Parcs Nationaux; DPN),


comprising scientists, decision makers andlocal people was tasked with developing,directing and evaluating a Salviniamanagement strategy. This met first inFebruary 2000 with Dr Arnold Pieterse(KIT/RTI). Recognizing the need forregional coordination, the managementstrategies of Senegal and Mauritania weredeveloped during and following furtherinter-country meetings held in April 2000and June 2001.

Participants at the February 2000 meetingagreed that biological control would be thelasting lynchpin of Salvinia management inSenegal too, with mechanical control beingused to provide rapid and short-termalleviation. While the biological controleffort was being set in motion, mechanicalremoval began to clear important water-ways and in particular keep backwaters andtributaries near the sluices for the DjoudjPark clean of Salvinia.

A joint civilian and military committee formechanical eradication (Comité Civilo-Militaire d'Appui au Développement;CCMAD) was coordinated by the Sociétéd’Aménagement et d’Exploitation du Deltade la Fleuve du Sénégal (SAED). CCMADcomprises representatives of local people,military personnel, Djoudj Park staff,regional water and forests inspectionservices, the tourist office and DPN.Funding for mechanical control came fromboth state and private sources and from theUN Development Programme (UNDP)Global Environment Facility (GEF).During 6 weeks in May-June 2000, 200civilians and military personnel put in 6000h to remove as much weed as possible (andparticularly to clear infestations upstreamof sluices), and to erect barriers to preventfurther spread into backwaters feeding thePark. More than 20,000 m3 of weed wasremoved, which provided short-termalleviation of the weed problem andcontributed to containment of its spread.Cost, however, was prohibitively high interms of manpower and fuel costs (5000litres of diesel fuel, for example, was used),and mechanical measures could delay butnot indefinitely prevent Salvinia's invasionof the Park and were not practical on thelarger scale needed for widespread control.

The biological control component of theSalvinia management strategy was placedunder the management of DPV (Directionde la Protection des Végétaux), which wastasked with coordinating efforts by nationaland international bodies. The first batch of300 weevils was imported from PPRI(shortly after weevils were introduced intoMauritania), financed by the Dutchgovernment via IUCN. The release of thesefirst weevils in Senegal ended in failure, as

a so-called 'starter' population was notcultivated at a protected site. Instead, all theinsects were released at unmarked sites inthe river where the infested plants could notbe kept together. Subsequent surveys failedto recover any weevils and it may beassumed that the small number of insectsbecame too dispersed to build up apopulation. With the support of the Dutchgovernment, IUCN imported 1200 moreweevils from South Africa in March 2001,a year later. A rearing operation was startedat the Biological Station (StationBiologique) in Djoudj Park in the frame-work of a new policy project of the EU,which is coordinated by RTI. In thiscontext, two Senegalese students at theUniversity of St Louis were trained inrearing techniques by PPRI, andsubsequently insects from their rearing pro-gramme were released in the Senegal Riverin the vicinity of the Park and in the Lac deGuiers. A UNESCO (UN Educational,Scientific and Cultural Organization)funded mission to Senegal in April 2001found that the rearing operations werebeing hampered by a severe lack ofresources at the Biological Station of DPN,however. The mission concluded that theoperational capacity in terms of logistics,materials and staff, could be improved.

Despite these misgivings, it soon becameapparent that the weevils were doing amagnificent job. Within 6 months of thisvisit, Salvinia plants were dying throughoutthe Senegal River, and their colour wasturning from green to dark-brown or black.Evidence for the weevils' wide dispersalwas seen both in Senegal and in Mauritania.In Senegal, Salvinia plants were infested atdistances far from the release sites near theDjoudj Park, and it may be assumed that theweevils had flown across from Mauritania,where they had been successfully releasedalmost a year earlier. A workshop held in StLouis in October 2001 on the problem ofinvasive plant species made it possible forthe participants, who came from all overAfrica, to see the Salvinia die off in theSenegal River with their own eyes.

Battle Won, War Continues

The rapid and spectacular invasion of theSenegal River delta by Salvinia capturedthe attention and stimulated action by local,regional, national and international stake-holders. However, the Salvinia explosion inthe River happened in the wake of thelargely unchallenged invasion by theequally damaging but less conspicuousspecies, Typha, along the river, inreservoirs and inside the parks.

Even worse could follow: water hyacinth(Eichhornia crassipes) is not far away and

threatens the ecosystem. During the StLouis workshop, participants learned thatwater hyacinth plants are being sold asornamentals at a plant nursery in the city.This does not pose an immediate threat toSt Louis, as the water in the Senegal Riverdownstream of the Diama Dam is toobrackish for water hyacinth to survive.However, if plants were somehow to betransferred to the river upstream of theDiama Dam, which is only 20 km away, anew ecological disaster would emerge.Water hyacinth is even more aggressivethan Salvinia and the available biologicalcontrol agents are less efficient thanCyrtobagous. The authorities announcedthat the plants would be destroyed. How-ever, as large numbers of water hyacinthplants are present in the markets of Dakar,extreme watchfulness remains a priority.

Thus, although first Pistia and nowSalvinia have been brought under control,invasive weeds continue to threaten theregion. In this sense, what is happening inthe Senegal River basin is an example of aproblem facing the whole continent: land-use change owing to population pressureand agricultural development is allowinginvasive species to threaten Africa'sbiodiversity, economy and health. Theagriculture, river traffic, hydroelectric andother developments that the dams on theSenegal River were built to help are underthreat from invasive weeds. The actions ofthe parties involved in the threat to theSenegal River basin, and in particular theconcerted and cooperative actions of thecountries in recognizing the need to includeinvasive species issues in management anddevelopment plans for the delta, provide agood model for other parts of the continent.

*Pieterse, A. (2000) Aquatic weedmanagement. In: Rijn, P.J. van (ed) Weedmanagement in the humid and semi-humidtropics. Amsterdam, The Netherlands;Royal Tropical Institute, pp. 169-176.

Websites:Djoudj National Bird Park:www.senegal-online.com/senega292.htmUNESCO World Heritage List:www.unesco.org/whc/sites/25.htmRamsar: www.ramsar.org/

Contact:Dr Arnold Pieterse, Royal TropicalInstitute, Mauritskade 63, 1092 ADAmsterdam, The NetherlandsEmail: [email protected]: + 31 20 6684579

M Sara Diouf, Directeur Adjoint, Directiondes Parcs Nationaux, PO Box 5135, Dakar-Fann, SenegalEmail: [email protected]: +221 252399

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M El Waled ould Mome, Director,Diawling National Park, PO Box 3935,Nouakchott, MauritaniaEmail [email protected]

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Black Wattle Problem Emerges in Indian Forests

Black wattle (Acacia mearnsii) is a fastgrowing leguminous tree native toAustralia. It is widely used as a source oftannin, fuel wood, charcoal, poles, greenmanure and windbreak. Suited to coolertropics, this tree grows well in tropicalareas where the annual rainfall is more than1000 mm.

Extensive areas of black wattle plantationshave been established in South Africa,South America, southern Europe andSoutheast Asia. The main purpose ofintroduction was for the commercialproduction of tannins, which is used forleather tanning and in products such aswood adhesive.

In Kerala State in southern India, A.mearnsii was introduced in the 1980s andmainly grown in the high altitude areas(over 1000 m above sea level; masl). It waspreferred over other candidate forestryspecies because of its fast growth rate andthe minimum post-planting care required.However, attempts to grow A. mearnsii ona plantation scale were not successful inmost places in Kerala owing to highseedling mortality, eco-climatic stress andother factors. Hence, it now occupies only avery small area in the State, and freshplanting is not undertaken because ofrecurrent failure in establishment.

The experiment with black wattleplantations has left an ominous legacy,however, for A. mearnsii has not simplygone away. Recent surveys conducted bythe Kerala Forest Research Institute (KFRI)indicate that in certain isolated pockets inthe high altitude areas, some trees of A.mearnsii survived against the odds and arenow growing luxuriantly, forming smallscrub jungles. At Vattavada (1800 masl) inIdukki District, it was noticed that, within aperiod of 3 years, A. mearnsii haspenetrated and spread over a 1 km2 area inthe dense subtropical montane (shola)forests, suppressing the native vegetation.Spread of the trees into the core areas of thehighly diverse shola forests atKolukkumalai (2480 masl) in the samedistrict was also observed. The highcompetitive ability and seed production,prolonged seed dormancy and high rate ofseed viability of the species probablyhelped the tree to spread like a wildfire into

these forests. Collection of branches andlogs of A. mearnsii by the local people forfirewood purposes will also have helpedspread of the tree species. Wild animalssuch as bison and deer also aid in seeddispersal. The allelopathic properties ofleaves and branches are other possiblefactors favouring the gregarious growth ofthe species.

Needless to say, the biodiversity of thesubtropical montane forests in Kerala isnow under great threat owing to thisunchallenged invasion by A. mearnsii.Control methods need to be consideredurgently, and in this context it should benoted that this species is a serious weed inSouth Africa, where it was introducedmuch earlier than in Kerala.

By: Dr K. V. Sankaran, Kerala ForestResearch Institute, Peechi – 680 653,Kerala, IndiaEmail: [email protected]

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Black Wattle: South Africa Manages Conflict of Interest

Australian Acacia (wattle trees) have beenutilized in South Africa since the 1820s forsand stabilization, garden ornamentals,timber and pulp production and tanninextraction. Their use has been widespreadand most of the 13 naturalized species forman integral, although not always welcome,part of South African socio-economicculture. Black wattle (Acacia mearnsii) isthe most economically important Aus-tralian Acacia present in South Africa, bothas a silvicultural crop plant and as aninvasive weed.

Black wattle is indigenous to southeastAustralia where it forms a commoncomponent of Eucalyptus forests. Thespecies was utilized initially in SouthAfrica as an ornamental as it appeared inthe 1858 catalogue of the Cape TownBotanical Gardens. However, thecommercial potential of black wattle wassoon realized by John van der Plank whocommenced the development of plantationsin KwaZulu-Natal in 1864, primarily forthe production of tannins, which areextracted from the bark. Black wattle barkis a rich source (31-51% dry weight ofbark) of water-soluble tannins, primarily3,7,3’,4,’5’-pentahydroxy-2-phenyl chrom,which is used for tanning leather and themanufacture of water resistant resins oradhesives for reconstituted wood products.Black wattle wood is also an importantexport product of South Africa with themajority being processed as pulpwood for

the production of paper and paperboardproducts. In 2001, South Africa exported1.2 million tonnes of black wattle woodproduct worth around R360 million(US$31.5 million) from 130,000 ha ofmanaged plantations centred in theprovinces of Mpumalanga and KwaZulu-Natal in northeast South Africa, and fromblack wattle control programmes. In 1998,the industry directly employed between10,800 and 13,000 people, mostly unskilledlabourers. In addition to this, black wattle isa source of firewood utilized for cookingand heating in lower income rural com-munities where it is also used for informalhousing and building construction.

Environmental Impact

Despite the economic virtues of blackwattle in South Africa, the tree has seriousenvironmental impacts, which are reflectedin its status as a weed of nationalimportance. Black wattle occurs on 2.5million hectares in South Africa mostly inthe southern and eastern sectors of thecountry where mean annual rainfallexceeds 500 mm. The invaded area is theequivalent of 131,000 ha of condensedinfestation and this is expected to increaseat 5-10% per annum without proactiveintervention. The main negative impactsassociated with black wattle are thereduction in surface stream flow with a netpresent value cost of R16,285 million(US$1425 million) (based on an annualwater consumption of 577 million m3), lossof biodiversity, and increased soil erosionand destabilization of river banks. Blackwattle has invaded grassland, fynbos,savanna and forest biomes in South Africaand is considered a threat to the species-richCape Floral Kingdom and many of thebiodiversity ‘hot spots’ of southern Africa.The potential for species’ reduction andloss is therefore substantial. The keyecological traits that contribute to thesuccess of black wattle are its ability todevelop large soil-stored banks of long-lived seeds that are triggered to germinateen masse by fire (a characteristic that isshared by many other Australian acacias)and the development of a large,structurally-dominating crown.

Biological Control

The vast scale of black wattle invasion inSouth Africa, coupled with the speciesnegative impacts, led in 1973 to theinitiation of a biological control pro-gramme that targeted the seeds of blackwattle. Organisms that could develop orfeed on vegetative parts of the plant werenot considered because of the directnegative impact these may have on theblack wattle industry. However, resistance


to research on seed-reducing agents forblack wattle mounted over the subsequentyears. The industry challenged the validityof the research programme by questioningthe status of black wattle as a seriousinvader, which had not been adequatelydocumented at the time. In addition,growers were concerned about the possibledepletion of seeds within plantations thatare required for natural regeneration ofcrops, and the protection of seed orchardsused for mass production of seed fromselected tree stock. The research effortshifted as a result of this conflict andfocussed on the biological control of otherinvasive, mostly non-commercial Aus-tralian acacias, particularly A. longifolia, A.melanoxylon, A. cyclops, A. saligna and therelated Paraserianthes lophantha (Mimo-saceae). As a result of this research, allthese species are now considered to beunder satisfactory, or partial, biologicalcontrol in South Africa using seed-reducinginsects and a host-specific gall-forming rustfungus. However, in 1987 the researchprogramme found itself again in conflictwith the black wattle industry when a seed-feeding curculionid, Melanterius servulus,proposed for the biological control of P.lophantha, was found to feed on seeds ofblack wattle in laboratory tests. The blackwattle industry opposed the release of thisinsect from quarantine due to concerns ofpotential damage the insect may cause toblack wattle seed supplies. The researchprogramme was suspended, but thenrecommenced following pressure byenvironmentalist and farmers affected by P.lophantha. A negotiated agreement wasachieved stipulating that releases of M.servulus could be made on P. lophanthaproviding it could be demonstrated thatblack wattle seed orchards could beprotected with insecticides. Syntheticpyrethroids registered for use in wattleplantations were found to cause highmortality in the field on the analogous M.ventralis, which develops in seeds of A.longifolia. As in vitro tests showed M.ventralis and M. servulus had similarmortality responses to these insecticides,the wattle industry accepted that seedorchards could be protected, should theneed arise. The beetle was formallyapproved for release in 1989 on thecondition that releases were confined to theCape Peninsula in the extreme southwest ofthe country, until it could be confirmed thatM. servulus would not attack black wattleunder field conditions. Subsequent fieldsurveys showed that M. servulus does notuse black wattle as a host and that feedingon this plant in laboratory tests was anartefact of confined, non-choice testconditions.

Conflict Resolution

Resolution of the potential conflict by anegotiated agreement, in retrospect, wasthe most pragmatic approach that couldhave been taken on this issue. Negotiationswere founded on basic trust and the abilityof both sides to acknowledge andunderstand each other’s concerns. Theeventual outcome was satisfactory to bothsides of the conflict, but the fact that it tookabout 25 years to resolve the issue using anadequately represented industry andbiological control research has been rightlycriticized. In South Africa today, biologicalcontrol research is governed by a process ofpublic consultation and liaison withaffected parties. In the case of black wattlebiological control, a steering committeewith industry representatives, researchersand other relevant organizations orindividuals, share in information transfer.Potential conflicts of interest are identifiedin the early stages. This process has nowbeen formalized as a mandatory procedureunder the National Environmental Manage-ment Act 1998 (No. 107). Although attimes the legislative process is admin-istratively clumsy and inefficient, it enactsthe principle of freedom of information andequitable consultation and is therefore aprogressive move.

Melanterius Seed Weevil

The resolution of the conflict of interestassociated with the release of M. servulus inSouth Africa opened the opportunity to re-commence the search for seed-reducingagents for black wattle. A small, univoltinebeetle, M. maculatus, that feeds ondeveloping seeds can be locally commonon black wattle and closely related Acaciaspp. (section Botrycephalae) in Australia.The beetle was approved for release in1993 after it was proven that non-targetspecies, particularly indigenous Africanacacias, were not accepted as hosts.Mounting public concerns over theenvironmental impact and continuedspread of black wattle in South Africa,coupled with the knowledge thatMelanterius could be controlled in seedorchards facilitated the process of approvalfor release. Once again, release approvalwas conditional, in that beetles would onlybe distributed in the Western Cape, to allowthe wattle industry time to prepare forfuture incursions of the beetle intoplantation areas. The insects have becomeabundant in the vicinity of their originalrelease sites, but their natural dispersal hasbeen slow. The beetle has not been detectedanywhere near the commercial wattlegrowing regions of South Africa.

Gall-Forming Fly

Black wattle is a difficult target forbiological control. The species inhabits abroad eco-climatic range in South Africa,has a high fecundity, sometimes aseasonalflowering and fruiting, and an early sexualmaturation period. These attributes make itunlikely that satisfactory control will beachieved by any single seed-reducingspecies. Although M. maculatus is causingincreasing levels of seed damage, sufficientseed reduction across the full range of blackwattle in South Africa will probably onlybe achieved by the additive effect ofcompatible seed-reducing insects. We areexamining the potential role of a gall-forming cecidomyiid midge as anadditional seed-reducing agent for blackwattle. Gall-forming insects have beenspectacularly successful in reducing seedloads on A. longifolia and A. pycnantha inSouth Africa by committing the plants toallocate host resources to gall formation atthe expense of fruits. This ‘forcedcommitment’ acts as a resource sink andvegetative performance of infected trees isreduced in the process. Clearly, this indirectimpact would not be accepted on blackwattle in South Africa, and indeed othercountries where the species is economicallyimportant. However, an undescribedcecidomyiid, Dasineura sp. has beendiscovered that forms flower galls (2-3mm) by causing the ovary to swell soonafter oviposition and form small, multi-chambered galls. Fruit production is thenprevented. A low biomass of galls, despitehigh infection levels, together with ashorter activity period compared to fruitdevelopment, releases the host tree fromresource commitment and could havebeneficial consequences on vegetativegrowth. The cecidomyiid appears to havesensitive host-finding abilities and as adultsare readily dispersed by wind, offers thepotential for effective seed-reduction ofblack wattle in South Africa. As with mostgall-forming cecidomyiids, the insect has anarrow host range and presents no threat toAfrican Acacia, which belong to differentsubgenera from Australian Acacia.

Protecting Seed Orchards

The issue of protecting black wattle seedorchards from attack by the cecidomyiid isparamount to the debate on whether thisinsect could be approved for release inSouth Africa. Trials utilizing a range ofinsecticide formulations on trees inAustralia will be undertaken to resolve thisproblem. Insecticide spraying for thesuppression of M. maculatus or Dasineurasp. in black wattle seed orchards willinvolve an additional cost to the industry.Indigenous pests such as foliage-feeding

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Lepidoptera can warrant pesticideapplication in plantations, but outbreaks aresporadic and annual applications are mostlynot necessary. Most wattle growers inSouth Africa (75%) regenerate treesfollowing harvesting using line-seeding,where treated seeds are drilled into the soil,especially in colder areas, or use nursery-raised seedlings from improved tree lines.About 1000 ha of seed orchard services thismarket in South Africa and would requireannual protection from seed-reducingbiological control agents should theseestablish within seed production areas. Allbut 18 ha of this area is dedicated to thecollection of seed for line-seeding thatyields around 3 t of seed per annum.Melanterius maculatus and Dasineura sp.have a period of overlapping adult activitybetween September and October andinsecticides applied to the tree canopyduring this time should limit the impact ofboth insects. A single application ofinsecticide is likely to be sufficient forcontrol of Melanterius, but several may benecessary for the Dasineura, if the totalpotential seed crop is to be protected, asadults emerge from the soil during theentire flowering period of black wattle.Systemic organophosphate insecticidesmay have a greater role in the protection oftrees from Dasineura than foliar-appliedsynthetic pyrethroids. The projected cost tothe wattle industry for the protection of1000 ha of seed producing plantations fromboth Melanterius and Dasineura sp. isbetween R115,000-R300,000 (US$10,000-26,000) per annum, based on the aerialapplication of cypermethrin at R110/ha.This cost could be reduced with improvedline-seeding techniques, which areconsidered wasteful of seed, or the phasingout of line-seeding in favour of replantingwith nursery-raised seedlings. This hasbeen the trend in many areas of SouthAfrica, and the implementation ofbiological control in wattle growing areascould accelerate this rate of change.

Natural Regeneration of Wattle Crops

Wattle growers that rely on natural seedlingregeneration as a method of crop re-establishment (25%) are unlikely to requireprotective insecticide sprays. Even in thepresence of biological control agents, lownumbers of seed will be produced that willaccumulate in the soil over the 10-year croprotation period. A single application ofsynthetic pyrethroid during a prolificflowering season would certainly guaranteeseed supply for the next crop. Also, severalsilvicultural practices will reduce theimpact of biological control agents. Afterclear-felling, there is a 2- to 3-year sexualmaturation period for flower production

and a 3- to 4-year period for fruitproduction. During this time, populationsof Melanterius and Dasineura will becomelocally extinct, and recolonization mustoccur from neighbouring sources at theonset of flowering or fruiting. The rate ofre-establishment of seed-reducing insectswill depend on the size of founderpopulations and their intrinsic rate ofincrease. Very little is known about thelatter for both Melanterius and Dasineura.Geographic and weather variables willinfluence the size of founder populationswith distance from the neighbouringsource, the nature of barriers between sites,and the direction of the prevailing windbeing most important. Plantations that areisolated are likely to experience slowcolonization by Melanterius and Dasineuraand seed production in the first few years ofthe establishing crop should be close tonormal. Alternatively, grouping two orthree consecutive seasons’ plantingstogether within a mosaic of non-Acaciaplantation species could reduce migrationrates and lower the impact of the insects onsubsequent seed crops. As black wattle isoften grown amongst blocks of Eucalyptusand Pinus, only minor changes to farmplanning would be required to implementthis model.

The ‘Sterile Tree’

Emerging technology is very likely to havean important impact on the way biologicalcontrol of black wattle seed is managed inSouth Africa. In an innovative initiativesponsored by the wattle industry, abreeding programme has commenced toproduce a ‘sterile tree’ throughmanipulation of the tree’s geneticcomposition using gamma irradiation, andthe formation of triploid trees. If successful,the sterile tree will produce no flowers orseeds, and if adopted by the wattle industry,biological control could be practised inSouth Africa with minimal conflict ofinterest. In this situation, the benefits of theindustry could be preserved while allowingwild black wattle trees to be freelysuppressed using biological control. It isthis situation that is expected to positivelychange the cost:benefit ratio of black wattlein South Africa from a current undesirable0.4 to 4.3. If this were achieved, the dividedperceptions of black wattle in South Africawould change to that of a generallywelcomed ‘guest’ with great utilitarianvalue. Also, effective implementation ofbiological control of black wattle seed inSouth Africa may greatly enhance theindustry’s success in seeking approval toexpand plantation areas to meet marketdemand for its products.

Black wattle is grown commercially inmany other countries and is reported tohave escaped cultivation in Tanzania,Zimbabwe, Swaziland, India, Madagascar,Hawaii, La Réunion, Brazil and NewZealand. The impact of naturalized blackwattle in these areas is largely unknown,but given the experience in South Africa, itis likely to be considerable or has thepotential to become so. Introduction ofseed-reducing biological control agents ofblack wattle to these countries, particularlyin the early stages of invasion, is likely toresult in massive long-term cost savings.

By: Robin Adair, Agricultural ResearchCouncil, Plant Protection ResearchInstitute, Private Bag X5017, Stellenbosch7599, South AfricaEmail: [email protected]: +27 21 883 3285

The author thanks S. Neser, B van Wilgenand J. Hoffmann for comments on anearlier version of this article.

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Harmonizing Weed Biocontrol in Australia

Over the coming issues of BNI you will bereading about a range of biological controlof weeds projects that are underway inAustralia with CSIRO (the CommonwealthScientific and Industrial Research Organ-isation). [See the next two articles, and alsoTraining News, this issue.] Here we givesome background to these initiatives, andoutline the development of the strategy ofcooperative action that lies behind them.

Weed control is a problem that is faced bymost farmers no matter what agriculturalproduction regime they belong to. Therewould be few farmers in Australia, orindeed around the world, who could claimto be running weed free properties, whetherthey are raising ostriches or growing trees.

In Australia weeds are the most widespreadproblem faced by growers, much more sothan salinity, for example. Weeds do notdiscriminate between natural environmentsor manipulated production systems, nor dothey stop at the farm fence or any border.Realizing this is an important step in weedcontrol, as is the realization that weedissues cannot be addressed one species at atime using only one technique. A holisticapproach to weed management is required.

One of the initiatives that is helping to bringtogether a range of weed control options inAustralia is the National Weed Strategy andthe relevant strategic plans associated withthe 20 Weeds of National Significance(WONS).


As well as thinking about weeds in aholistic manner, organizations involved inweed management need to work together.A major step towards greater collaborationwas taken in 1995 when the CooperativeResearch Centre (CRC) for WeedManagement Systems was established andthis has continued with the commencementof the new CRC for Australian WeedManagement in July 2001. The originalWeeds CRC formally brought togetherleading organizations involved in weedcontrol and was a catalyst in the integrationof various weed management practices.The new Weeds CRC takes this collab-oration one step further and incorporatesnorthern Australia, allowing a trulynational approach to weed management.

One of the options in weed management isbiological control, the use of naturallyoccurring invertebrates (such as insects) orpathogens (fungi) to control plants thathave become weeds. Biological controldoes not eradicate a weed, but if successfulit can restore Nature’s balance to a pointwhere the weed is no longer of economicimportance. Currently it is estimated thatagricultural weeds in Australia cost morethan Au$3.3 billion per annum, so reducingthat economic impact by even a smallfraction would be a major achievement. Formany years, CSIRO Entomology has beeninvolved in the biological control of a rangeof agricultural and environmental weeds.Some of these weeds are on the WONS listas part of the National Weed Strategy.

There are currently a number of agriculturalweeds that are targets for biological controlby CSIRO. For temperate Australia,projects exist for Paterson’s curse (Echiumplantagineum), Onopordum thistles, nod-ding thistle (Carduus nutans), Scotchbroom (Cytisus scoparius), Emex and blueheliotrope (Heliotropium amplexicaule).New projects have recently commenced onwild radish (Raphanus raphanistrum) andserrated tussock (Nasella trichotoma),although it will be some years before agentsare released and established on these latterweeds. For environmental weeds, agentshave been released on bridal creeper(Asparagus asparagoides), bitou bush andboneseed (Chrysanthemoides moniliferaspp.), horehound (Marrubium vulgare),blackberry (Rubus fruticosus), St John’swort (Hypericum perforatum) and Scotchbroom with work commencing onMontpellier broom (Genista monspes-sulana).

In tropical Australia agents have beenreleased on mimosa (Mimosa pigra),parkinsonia (Parkinsonia aculeata),mesquite (Prosopis spp.) and sida (Sidaacuta) and research is being conducted into

control for Mexican poppy (Argemonemexicana), Hyptis and bellyache bush(Jatropha gossypiifolia).

The impact from some of these agents isonly just starting to be felt becausebiological control is a long-term option.Some of the target weeds have been inAustralia for over 100 years, and it wouldbe blithely optimistic to expect the agents toreverse a century of damage in the space ofa year or two. For instance, for most weedsthere is a huge build up of long-lived seedin the soil and this stock of seeds must bedepleted before any kind of control can beaffected. In some cases this amounts tohundreds of thousands of seeds per squaremetre of soil, all waiting to germinate andall capable of surviving for up to 10 years ormore.

As organizations work more closelytogether, biological control is increasinglybeing looked at as an important componentin overall weed management, rather than asa last resort when all else has failed.Research into the integration of biocontrolagents with other management practices isallowing Weeds CRC researchers todevelop best practice management guidesthat will ultimately provide landownerswith a package of information that they canimplement on their properties.

Contact: Kate Smith, CSIRO Entomology,GPO Box 1700, Canberra, ACT 2601,AustraliaEmail: [email protected] +61 2 6246 4177

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Rollers Released on Australian Coastal Weed

Bitou bush (Chrysanthemoides moniliferarotundata) is a major conservation weed ofcoastal southeastern Australia and throughthe National Weeds Strategy is listed as oneof Australia’s 20 Weeds of NationalSignificance. [See also BNI 20(4), 108N(December 1999) ‘Speedy seed fly’.]

One more biological weapon has now beenadded to the assault on this South Africanconservation menace and it comes in theform of a moth. The leaf-rolling moth(Tortrix sp.) is the most damaging insectfeeding on bitou bush in its homeland,South Africa, and is the sixth biologicalcontrol agent to be released on this weedalong the New South Wales (NSW) coast.

Bitou bush was first recorded in NSW inthe early 1900s and from 1946 throughuntil 1968 it was deliberately planted alongthe NSW coast to aid control of erosion andpost-mining rehabilitation. It was so

successful in this role that it continued toinvade coastal habitats in southeasternQueensland, NSW and Lord Howe Island.Bitou bush is particularly prevalent on thecentral and north coasts of NSW and thetotal area infested in Australia is nowestimated to be over 70,000 ha.

CSIRO Entomology, in collaboration withthe Cooperative Research Centre forAustralian Weed Management and NSWAgriculture, has attracted funding throughthe National Heritage Trust to allow therearing, release and evaluation of the leaf-rolling moth. The moth was first releasednear Grafton NSW in 2001 and subsequentreleases have been made along the NSWcoast from Moruya in the south to theQueensland border.

The life cycle of the leaf-rolling moth takesabout 8 weeks from egg to adult, dependingon the season. Eggs hatch after about 8 daysand the larvae move to the shoot tips wherethey begin to feed. The larval stage lastsabout 30 days and during this time thelarvae feed on leaves, stems and surfaces ofyoung shoots resulting in death of shoottips. High larval populations in summer,when the insect is most active, mayseverely defoliate, weaken or kill plants.The larvae then pupate for around 10 daysand then live as adults for about 14 daysduring which time they mate, lay eggs andthe cycle begins again.

Biological control agents, like thepreviously released tip moth and seed fly,as well as the leaf-rolling moth, comple-ment each other and increase pressure onbitou bush, making it less competitive.Biological control is a long-term strategyfor control and is most often best used witha combination of other control methods.The best combination to achieve control isoften site specific, but may includeherbicide, manual removal or fire.

Once the weed has been removed from anarea it is important to ensure that anotherweed does not take its place. Revegetationof heavily infested areas has a major role toplay in the prevention of further problems.


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Australia's Two-Step Strategy for Blue Heliotrope

The mauve coloured flowers of the deadlySouth American blue heliotrope (Helio-tropium amplexicaule) infest thousands ofhectares in eastern Australia. Originallyintroduced in the 19th century as anornamental garden flower, blue heliotropehas now spread from southern Queenslandas far south as the Victorian border and intoSouth Australia. It is poisonous to stock,causing liver damage that can result in lossof condition and often death.

The first biological control agent, the leaf-feeding beetle Deuterocampta quadrijuga,was released on 21 November 2001. Therelease of this beetle is due to the efforts ofthe Blue Heliotrope Action Committee ofnorthern NSW, who continued to seeksupport for biological control and weresuccessful in gaining funding through theRural Industry Research and DevelopmentCorporation (RIRDC).

In the early 1990s CSIRO conductedsurveys in South America that identifiedsome insect species as potential biologicalcontrol agents. However, at the time blueheliotrope did not attract sufficient industryfunding, so no further work was done andthe plant continued to spread. After a longdelay CSIRO was able to begin in earnest in1998. Professor Miguel Zapater of theUniversity of Buenos Aires, Argentinacame on board to study the biology of anumber of the potential agents that wereidentified in the earlier study. As a result,D. quadrijuga and Longitarsus sp., a flea-beetle whose larvae feed on the roots, wereprioritized for the biological control of blueheliotrope.

In March 2000, CSIRO received the firstbatch of D. quadrijuga eggs. The larvaeand adults of the beetle feed on leaf tissueand can cause complete defoliation of theweed. They were reared in quarantine andspent a year and a half being tested toensure that they would be safe to releaseinto the Australian environment. Testsshowed that the beetles only attacked theSouth American blue heliotrope and did notpose a risk to non-target plant species,including native Australian Heliotropiumspecies.

Based on these results, in July 2001Australian Plant Biosecurity authoritiesapproved the release of the beetle for thebiological control of blue heliotrope.Efforts are currently underway to obtainfunding for host-specificity testing of theflea-beetle and eventual redistribution of

these agents throughout the infested areasof southeastern Australia.

It is hoped that the planning and evaluationcarried out thus far will bring the desiredresults of curtailing the unchecked spreadof blue heliotrope and limiting its impact inthe areas in which it has gained a presence.


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Cocktail for a Sharpshooter

The vineyards of California are under threatfrom an old enemy given a new lease of lifeby a new ally, the glassy-winged sharp-shooter (GWSS), Homalodisca coagulata.Pierce's disease, a serious malady of grapes(caused by the xylem inhabiting bacteriumXylella fastidiosa) was first identified inCalifornia over a century ago. Thebacterium produces xanthan gum, whichblocks the xylem vessels. The leaves ofdiseased plants typically develop drying orscorching symptoms, and the vines becomeunproductive and usually die within 1-2years of infection. GWSS is a xylem-feeding insect that readily acquires andtransmits X. fastidiosa. Currently, there isno known cure for eliminating the diseasefrom infected vines.

In rapid response to this deadly alliance, aninter-disciplinary collaborative effort in-volving the US Department of Agriculture– Agricultural Research Service (USDA-ARS) and Animal and Plant HealthInspection Service (USDA-APHIS), theCalifornia Department of Food andAgriculture (CDFA), County-based Co-operative Extension Personnel, theUniversity of California (UC) and industryand private organizations planned andlaunched a multi-pronged attack tosimultaneously manage the threat posed bythe GWSS-Xylella combination. Its goalsare to contain the sharpshooter's spread,and at the same time develop a cocktail ofcontrol and curative measures to protect thewine industry in the south of the state fromfurther devastation. A meeting held in SanDiego, California in December 2001provided an opportunity to reviewprogress.

Until recently, Pierce's disease was spreadby native sharpshooters, principally theblue-green sharpshooter (Graphocephalaatropunctata). These are poor fliers andprefer other plants in preference to grapesfor feeding. However, even G.

atropunctata was able to bring about thedestruction of the Orange County wineindustry in the late 19th century. During the1880s Pierce's disease decimated more than16,000 ha of grapes in the Anaheim area.The incurable disease has appeared on andoff ever since, but its spread was limited.Farmers in most parts of the state were ableto control it by pruning infested branches,grubbing out infected vines, and replanting.

The status quo was shaken by the arrival inCalifornia of H. coagulata, a cicadellidnative to the southeastern USA. Firstidentified in the state in Ventura County in1990, it began wreaking havoc in 1999when the first disease outbreak occurred inthe vineyards of Riverside County'sTemecula region. Much larger, vagile, andmore robust than native sharpshooters, itspreads the disease much more efficiently.Moreover, it has a recorded host range ofover 70 species, and thrives in urban andrural environments. As well as Pierce'sdisease, it can transmit diseases such asoleander leaf scorch (in California), phoneypeach disease (in the southern USA),almond leaf scorch and alfalfa dwarf. InCalifornia, GWSS has two generations peryear and overwinters as adults. It can flydistances over 400 m and up to heights of 8m, frequently appears in high numbers, andsurvives winter temperatures dipping to −6.5°C in citrus orchards. It spreadthroughout the wine producing areas ofsouthern California, and into the south ofthe San Joaquin Valley threatening thetable grape industry there. Current losseshave been estimated at US$14 milliondollars-worth of damage to the wineindustry in just a few years. GWSS has nowestablished in San José and threatensCalifornia’s premier wine producing areasof Napa, Sonoma, and Mendocinocounties.

A state-wide management programmeincludes survey activities to determine thedistribution of GWSS in California anddetect new infestations, and regulatoryactivities to prevent artificial spread touninfested at-risk areas. In this context, UCCooperative Extension (UCCE) haslaunched an information campaign to alertgrowers and enlist their assistance inmonitoring for the disease.

Biological control is seen as the keyingredient in an IPM solution. One nativeegg parasitoid, Gonatocerus ashmeadi, isalready abundant in California, but isprimarily effective during the summer.Researchers at UC Riverside are evaluatinganother species from the same genus, G.triguttatus, which attacks earlier in theseason, and could potentially depressnumbers of first generation sharpshooters.


In cooperation with CDFA, they havereleased G. triguttatus reared from stockimported from Texas and Mexico invineyards and citrus groves in Riverside,Ventura, and Tulare counties, and are nowwaiting to see whether this species cansurvive the Californian winter.Additionally, UC Riverside researchers arelooking at the preferences of parasitoids forGWSS of different ages to assist with massrearing efforts of these natural enemies.The outcomes of competition betweendifferent species of egg parasitoids forGWSS egg masses of different ages arebeing studied to determine if new naturalenemy additions to California will becomplimentary or antagonistic to GWSScontrol. One other area that is beinginvestigated is the importance of flowersand other sugar sources for helping increasethe longevity and fecundity of GWSSparasitoids in citrus orchards and vine-yards. This strategy may be particularlyimportant for helping parasitoids survivethrough the winter to attack the springgeneration of GWSS eggs. The springGWSS egg population currently suffersfrom low levels of parasitism (around 30-60%) by G. ashmeadi. Summer levels ofGWSS egg parasitism by G. ashmeadi aremuch higher, often exceeding 95%.

Scientists at the USDA-ARS BeneficialInsects Research Unit in Weslaco, Texasare looking at egg parasitoids found insouth Texas, Louisiana and northeasternMexico. Surveys in south Texas during2001 showed that 86% of GWSS eggmasses were attacked by the parasitic wasp,G. triguttatus. This species will continue tobe released in California during 2002.Gonatocerus fasciatus is one species beingtargeted for importation into Californiafrom Louisiana this year. Natural enemiesin the home range of GWSS are thought tobe at least partly responsible for the lowdensities of sharpshooters in these regions.At the same time USDA is conductingDNA analysis on the Californian sharp-shooters, and comparing results withpopulations from elsewhere to try anddetermine the source of origin of theinvasion. The results may help delineatewhere the most effective biocontrol agentsmight be found.

Exploration for sharpshooters and morenatural enemies, though, is already beingconducted in South and Central America.At the USDA-ARS South AmericanBiological Control Laboratory in Argen-tina, scientists are surveying and collectingparasitoids from the eggs of the SouthAmerican sharpshooter, Tapajosa rubri-marginata, collected from areas ofArgentina with subclimates similar to those

found in the grape-growing regions ofCalifornia. Over a dozen species of eggparasitoids have been collected. Shipmentsto US quarantine for evaluation againstGWSS are expected to begin in 2002.Parasitoids or other sharpshooter naturalenemies from similar subclimates mightoutperform natural enemies imported fromdifferent climates. Chile, also, has somegood climate matches and is being includedin new explorations for new biologicalcontrol agents.

Even good biological control will notprovide a complete answer to the GWSSproblem, as small numbers of insects canstill transmit disease and wreak havoc.(Consequently, there is not a viable grapeindustry in areas of the USA where GWSSis native.) Biocontrol will therefore be justone part of the GWSS managementstrategy, and other possibilities includingchemicals (insecticides and bactericides),cultural control (barriers), breedingprogrammes (traditional and transgenic),and monitoring strategies (for GWSS andXylella) are being investigated.

Plant resistance is a good complementarytool for biocontrol, but currently there areno commercial vines resistant to Pierce'sdisease. Research is focused oninvestigating the molecular mechanisms ofsusceptibility to X. fastidiosa, and also oninvestigating mechanisms of resistance inwild grapevine relatives that do not developthe disease. With this information, classicalbreeding or biotechnology could beemployed to create a vine more resistant toXylella.

Making vines physically unattractive to thesharpshooter is another approach. USDA-ARS scientists in West Virginia have foundthat a coating of white kaolin particlesmakes them inhospitable. Field trialscoordinated by USDA-APHIS in vine-yards, some bordering citrus orchards, inKern County, California gave encouragingresults. Three treatments applied from mid-March to mid-April resulted in sharp-shooter numbers lower than those found oninsecticide-treated vines. In addition, thekaolin treatments were cheaper than sixinsecticide treatments. It could provide apromising non-toxic early-season alter-native to insecticides. It may not be suitablefor use once the vines have bloomed, asvisible white kaolin residues on grapes,although harmless, do affect wine qualityand would probably be unacceptable toconsumers.

Innovative biotechnology may allow thecausal agent of Pierce's disease to betargeted. Armed with the full genomesequence of X. fastidiosa, scientists at UC

Riverside are studying some 100 genesthat, if removed, could render the bacteriumharmless by preventing transmission orinfection. To be successful, the modifiedbacterium would need to be able tooutcompete the wild-type disease-causingform. An alternative strategy is to useanother a bacterium or virus to kill Xylella.This would entail using bioengineeringtechniques to modify an antagonist fromthe gut of the sharpshooter to produceenzymes lethal to X. fastidiosa. Infectedsharpshooter populations could potentiallypass this on from generation to generation.A candidate bacterium has been shown toreproduce in the sharpshooter gut. Now asuitable lethal gene is being sought, whichwould need to be inserted into thebacterium, and then application technologywould have to be developed, and of courserigorous safety standards would have to bemet before any genetically modifiedorganism could be released. Anotherpotential method for disarming X.fastidiosa is to prevent it producing thexanthan gum, the substance that damagesand eventually kills the plant. Somebacteria are known to break down xanthan,and the search is on for one that does thisinside diseased grapevines. Although thesetools are at an early stage of development,they could be a powerful boost for controloptions.

The wide host range of GWSS causesparticular problems. A variety of commonweeds can carry X. fastidiosa, and thisreinforces the importance of good weedcontrol to prevent disease spread. Inaddition, fava bean, a common cover cropin vineyards in northern California, canalso host the bacterium, and legume cropsare now contra-indicated as crops invineyards.

The sharpshooter is especially problematicwhere citrus and vines are cultivated inclose proximity. Although GWSS cantransmit disease in citrus, these pathogensare not found in California, and thesharpshooters feed and reproduce in citruswithout causing significant damage. Theytend to overwinter in the citrus trees'protective foliage and move out to colonizevineyards in spring. Trials coordinated byUC Davis Extension Service staff in KernCounty demonstrated that contactinsecticide applied to citrus in winterreduces adult numbers, while a follow-upsystemic treatment in spring targets thewingless nymphs, which are confined to theplant they hatch on. Thus fewer survive tomove onto the vines when they mature. Inseparate trials conducted by the USDA-ARS Western Cotton Research Laboratoryin Arizona and UC Riverside researchers,

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pyrethroids and neonicotinoids gave fastestknock-down of the pest, with onepyrethroid compound giving 100% kill in 6hours. Compound residues from bothclasses also continued to give goodknockdown beyond 28 days. However,resistance development is a major concernwith sole reliance on insecticides forGWSS management.

An additional problem with this approach,however, is that significant areas of citrusare under IPM for primary pests or underorganic production. Therefore, consid-erable grower resistance to paying for andusing insecticides for a pest that is not aproblem in citrus is being experienced anddisruption of stable IPM programmescaused by broad spectrum pesticide use isresulting. GWSS control where organic orIPM citrus borders grapevines is thusparticularly difficult and controversial.Although biocontrol by egg parasitoids andother compatible measures are expected toalleviate the problem to some extent, theintroduced parasitoids will take time tohave an impact in citrus, wilderness andresidential areas. In the meantime, cagetrials to test the efficacy of augmentativereleases of commercially produced greenlacewing larvae (Crysoperla rufilabris)conducted by CDFA scientists in thesouthern San Joaquin Valley gavepromising results. Further trials are plannedwith other commercially available preda-tors. Results of trials in organic lemonshave reduced sharpshooter numbers,although not as much as in conventionallytreated citrus.

USDA is also researching alternatives tochemical pesticides for killing the eggswithout affecting natural enemies.

Contact: Mark S. Hoddle, Department ofEntomology, University of California,Riverside, CA 92521, USAEmail: [email protected]: +1 909 787 3086

Walker Jones, USDA-ARS, Kika de laGarza Subtropical Agricultural ResearchCenter, Beneficial Insects Research Unit,2413 East Highway 83, Weslaco, TX78596, USAEmail:[email protected]: +1 956 969 4888

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New Legislation Benefits Weed Biocontrol in South Africa

Biological control, by definition, does notresult in the complete eradication of thetarget weed. The continuous presence of

remnant populations of the target weed is aprerequisite of sustainable biocontrol; yet itis this aspect that often brings biocontrolinto conflict with weeds legislation,because legislation usually requires thetotal and immediate eradication of declaredor noxious weeds.

Until recently, this has also been thesituation in South Africa, where biologicalcontrol has not always been recognized bylaw as a viable, long-term control measurefor alien invasive plants. Severalpotentially successful biocontrol projectshave been impeded by the insistence of therelevant authorities that herbicides ormechanical control, often in an attempted'eradication', be applied as soon as thepopulations of biocontrol agents go througha temporary depression that is part of theirnatural population cycle. Other biocontrolprojects never got off the ground becausethe authorities were not prepared to risk thephasing out of the herbicidal regime infavour of biological control. Stands ofdeclared weeds under complete biologicalcontrol have frequently been clearedchemically or mechanically by order of theauthorities or out of ignorance, resulting inthe loss of valuable biocontrol material.

The recent amendment of the relevantlegislation in South Africa has gone a longway to rectify this situation. During March2001, regulations 15 and 16 of theConservation of Agricultural ResourcesAct (CARA) were drastically revised.Despite a much tougher stand on weeds, asreflected by the substantial increase in thenumber of plant species that are now eitherprohibited or regulated, some imaginativechanges in the regulations havesignificantly improved the prospects forbiological control.

In the original 1983 version of CARA,harmful plants were divided into 46 speciesof declared weeds (which had to beeradicated) and 35 species of invader plants(which needed to be controlled in ruralareas only, if they were threatening anyagricultural resource). Of these invaderplants, ten species were alien plants, whilethe other 25 were indigenous species. Bymaking no distinction between alieninvaders and indigenous species thatbecame unnaturally abundant only as aresult of inappropriate managementpractices, several valuable indigenousspecies were placed under unnecessary'suspicion' in well-managed areas in whichthey were not causing problems. Noprovision was made for dealing with plantspecies that were clearly harmful in certainsituations, yet were valuable to part of thepopulation.

The amended CARA regulations separatealien problem plants (discussed underregulation 15) from indigenous ones (dealtwith under regulation 16), differentiatebetween three categories of alien problemplants, and are unique in making speciallegal provision for biological control.

Classification of Problem Plants by theCARA Amendments

Bush encroachment indicators. Theindigenous problem plants (44 species) arenow called 'indicators of bushencroachment'. The amended regulationsdisplay an understanding of the ecology ofbush encroachment by advising land usersto take extra care in areas characterized bythe listed species. In addition, theyprescribe ecologically sound managementpractices aimed at preventing bushencroachment and at combating it where italready occurs.

Declared weeds and invader plants. Alienproblem species are subdivided into threecategories, based on their current utilization(or lack thereof) in South Africa.

1. The greatest proportion of alienproblem plants (124 species) are thosethat have no function to fulfil in SouthAfrica or whose harmfulnessoutweighs any useful properties theymight have. These were placed intoCategory 1, and are called 'declaredweeds'. This denotes that they areprohibited and must be controlledwherever they occur. The onlyexception is that they may grow inbiological control reserves (discussedlater).

2. A much smaller group (35 species)consists of invasive plants thatnevertheless have certain beneficialproperties that warrant their continuedpresence in certain circumstances.These were placed into Category 2,and (together with Category 3 plants)are called 'invader plants'. They havecommercial, structural or utility valueas timber, fruit or medicinal plants, soilstabilizers, wind breaks or sources offodder, fuel or building material. Landusers will be allowed to cultivate orretain these species on condition thatthey take the necessary responsibilityfor the water use and seed pollution bythese trees. Permission has to beobtained from the Executive Officer,who will demarcate a specific area forthe growing of a particular Category 2plant species. Category 2 plantsgrowing anywhere except in suchdemarcated areas or in biologicalcontrol reserves will be regarded asdeclared weeds, and will have to becontrolled. Category 2 plants may be


sold only to, and purchased only by theusers of areas demarcated for theparticular species.

3. Another group of 'invader plants',placed into Category 3 (39 species),consists mainly of popular ornamentalplants. It was considered unnecessar-ily harsh to prohibit them outright,and instead a ban was placed on allnew plantings. The existing speci-mens of Category 3 plants, exceptthose growing in or near watercoursesor wetlands, may be retained untilthey die naturally. In cases wherethese plants threaten any agriculturalresource, the Executive Officer hasthe authority to enforce additionalmeasures. No further trade in Cate-gory 3 plants will be allowed, plantsmay no longer be propagated and allseedlings must be controlled.

Another feature of the recent amendmentsto the CARA legislation is that certainsterile or less invasive forms of plants fromCategories 1 to 3 may be grown and soldlegally. Examples include the steriledouble-flowered cultivars of Neriumoleander, the sterile form of Lantanamontevidensis, all spineless cactus pearcultivars and selection of Opuntia ficus-indica, the sterile cultivar ‘Rubrum’ ofPennisetum setaceum, and all cultivars ofPyracantha angustifolia. Similarly, severalplant species were placed into differentcategories in different provinces, based onthe climate in which they are likely tobecome invasive. Examples are Acaciadealbata, which is a declared weed in theWestern Cape Province and a Category 2invader plant in the rest of the country;Ardisia crenata, which is a declared weedonly in the Northern Province, KwaZulu-Natal and Mpumalanga, and Schinusterebinthifolius, which is a declared weedin KwaZulu-Natal and a Category 3invader plant in the rest of the country.Most of these exemptions were negotiatedin consultation with the nursery industry.

Implications for Biological Control

Control of weeds and invaders instead oferadication. The amended CARA reg-ulations do not insist on the eradication ofall declared weeds or invader plants thatgrow in areas where they are forbidden bylaw, but only on their control. CARAdefines 'control' as: “the combating ofplants by means of the prescribed methods”(including biological control), “to theextent necessary to prevent or to contain theoccurrence, establishment, growth, multi-plication, propagation, regeneration andspreading of such plants”.

This formulation allows scope forbiological control. Seed-destroying insectshave the potential to prevent or contain theestablishment and spreading of the targetweeds, e.g. the snoutbeetles Melanteriusspp. that destroy up to 100% of seedsproduced by several Australian Acaciaspp., aided in certain cases byinflorescence-galling wasps (Trichilogasterspp.); the flowerbud-feeder Trichapionlativentre together with the seed-feederRhyssomatus marginatus that almostobliterate seed production in Sesbaniapunicea and the combination of a fruitweevil, Erytenna consputa and a seedmoth, Carposina autologa, which togetherdestroy the vast majority of newlyproduced seeds of Hakea sericea, as well asseeds accumulated on the plant. Naturalenemies that weaken their target plant byattacking its vegetative growth can be saidto contain the plant’s growth, propagationand regeneration. Examples are the'nutrient sink' effect of the gall wasps(Trichilogaster spp.) mentioned above, andthe leaf, bark and flower feeding beetlesLeptinotarsa texana and L. defecta thatreduce the photosynthetic surface anddeplete the nutrient reserves in therhizomes of Solanum elaeagnifolium, thuscontaining its growth and vegetativereproduction, and preventing fruit set byfeeding on the flowers. In all the casesmentioned above, effective biologicalcontrol complies with CARA’s definitionof control.

Recognition and safeguarding of biologicalcontrol. The CARA regulations prescribethe following control methods, as long asthey are appropriate for the particularspecies and ecosystem:

• uprooting, felling, cutting or burning

• treatment with registered herbicides

• biological control carried out inaccordance with the stipulations of allthe relevant Acts

• any other method recognized by theExecutive Officer

• a combination of the above, except thatbiocontrol reserves and areas wherebiocontrol agents are effective, shallnot be disturbed by other controlmethods to the extent that the agentsare destroyed or become ineffective

Today this is probably the only weedslegislation that specifically mentionsbiological control as an acceptable controlmethod.

CARA goes even a step further byprotecting biological control frominterference by other control measures. Anexample of such interference, which would

now be regarded as illegal, was theenforced herbicidal treatment of Opuntiaaurantiaca in areas where the cochinealDactylopius australis was effectivelycontrolling the cactus. This used to happenfrequently in the Eastern Cape Province,especially while the cochineal populationswere at the bottom of a natural curve, butstill managed to keep the weed populationbelow the economic damage threshold. Astate subsidy on the registered herbicide,MSMA, encouraged land users evenfurther to use herbicides instead ofbiological control. Nevertheless, theherbicide campaign against this weed was afailure, despite being the country’s mostexpensive weed control project. Wherebiological control was given an opportunityto reach its full potential, O. aurantiaca isno longer a problem. The same applies toHypericum perforatum in the WesternCape Province.

Biological control reserves. Biocontrolresearchers need protected areas in whichto monitor the establishment andperformance of newly-released biocontrolagents, even though the agents cannot yetbe expected to exercise effective control oftheir target weeds. Protected areas forbiocontrol agents also serve the purpose ofletting the agents build up their numbers toallow their collection and mass-release intonew areas, or to enable the agents tocolonize recently cleared surrounding areasas their target weed regenerates. Mindful ofthese requirements, CARA provides for thedesignation of biological control reserves.

Biocontrol reserves will be designated bythe Executive Officer, on application inwriting by a biocontrol researcher orpractitioner (“biological control expert”). Itwill be illegal to destroy the biocontrolagents in such a reserve, or to do anythingthat will reduce their efficacy. Thisstipulation implies that a mechanism has tobe created by which all persons involved inthe control of alien invasive plants areinformed of the whereabouts of biologicalcontrol reserves.

Biocontrol as an Instrument forResolving Conflicts of Interest

Biological control in the form of seed-destroying agents has the potential torestrict the invasive potential of a formerlyinvasive plant species without interferingwith its utilization. This is illustrated by theuse of the curculionid, Melanterius acaciaeto destroy the seeds of the valuableAustralian timber species, Acaciamelanoxylon, without affecting the qualityof the wood. Different Melanterius spp.have been released to reduce the invasivepotential of several Australian Acacia spp.

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in South Africa [see also 'Black wattle:South Africa manages conflict of interest,this issue]. Similarly, the bruchids,Algarobius prosopis and Neltumiusarizonensis, which destroy the embryos inthe seeds of Prosopis spp. withoutsignificantly reducing the nutritional valueof the pods, allow the continued utilizationof this valuable shade tree and source ofstock feed. In this case, the efficacy of seeddestruction depends on the measures thatare taken to keep the pods away from thelivestock until the beetles have had theopportunity to complete their life cycle inthe seeds.

The availability of biological control as aconflict resolving tool was one of thefactors that has made it feasible for CARAto allow persons to continue farming withinvasive plant species, such as Acaciamearnsii, Acacia melanoxylon, Prosopisspp. and several Pinus species. Category 2plants may be grown only in legallydemarcated areas and under controlledconditions. One of the few practicable waysfor the land user to comply with therequirement of preventing or restricting thespreading of the invader plant from thedemarcated area is by releasing host-specific seed-destroying natural enemies.Without this option, the present Category 2plants would probably have had to beincluded under Category 1 (declaredweeds). This step would have caused suchan outcry by the present users of these plantspecies that Government would most likelyhave withdrawn all the species concernedfrom legislation altogether, leaving them toinvade the country unchecked.

Seed-destroying biocontrol agents alsohave a function to fulfil with regard toCategory 3 invader plants (mainlyornamental trees). Despite the general banon further planting of Category 3 plants, aclause was included whereby the ExecutiveOfficer may grant exemption from thisstipulation, amongst others. Such anexemption will only be granted if theExecutive Officer is satisfied that the risk ofinvasion was minimal, e.g. if the climate isunsuitable for seedlings to survive, or ifseed production is negligible. The cityplanners of Pretoria and Johannesburg

might invoke this exemption clause toobtain permission to continue plantingjacaranda trees along their roads oncondition that a host-specific seed-feedinginsect be introduced and released againstthis popular street tree.

Conclusion

The amended CARA regulations might beunpopular because of the inclusion of sucha large number of popular plant species:every farmer, forester, landscaper andnursery owner – in fact almost everylandowner – is now at risk of transgressingthe law, albeit inadvertently. With regard tobiological control of alien invasive plants,however, the amendments create anawareness of this control method amongstthe authorities, promote its use and itsintegration into management strategies, andsafeguard the valuable agents that havebeen released into the field. The country issure to reap the benefits of this forethoughtin the form of improved, cost-effective andsustainable control of invading alien plants.

Further Reading

These three key publications givebackground information on the weedprogrammes referred to in this article.

Hoffmann, J.R. (ed) (1991) Biologicalcontrol of weeds in South Africa.Agriculture, Ecosystems and Environment,Special issue, 37(1-3), 255 pp.

Olckers, T. & Hill, M. P. (eds) (1999)African Entomology Memoir No. 1.Biological Control of Weeds in SouthAfrica (1990-1999), 182 pp.

Olckers, T.; Zimmermann, H.G.; Hoffmann,J.H. (1998) Integrating biological controlinto the management of alien invasiveweeds in South Africa. Pesticide Outlook9(6), 9-16.

See also the two PPRI handbooks describedin ‘New Books’, this issue.

By: Hildegard Klein, ARC-Plant Pro-tection Research Institute, Private BagX134, Pretoria 0001, South AfricaEmail: [email protected]: +27 12 3293278

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Portuguese Leave British Standing!

Which would you least like to have to workwith: an invasive impenetrable thicket-forming, intensely prickly shrub, or aminute, almost immobile insect controlagent? Spare a thought for scientistsinvolved in gorse (Ulex europaeus)biocontrol in New Zealand, then, for theyhave both to contend with. The gorse thrips(Sericothrips staphylinus) imported fromthe UK and released in New Zealand some10 years ago has the dubious honour ofbeing named “slowest moving biocontrolagent of all time” by Landcare Research.

As this 1- to 2-mm-long, usually winglessinsect had not dispersed far beyond itsoriginal release sites, it was clear to thescientists involved that it would need afairly massive redistribution exercise if thecontrol programme were to succeed. Notentirely surprisingly, they found the publicreluctant to help – not just because of thegorse prickles, but also because the size andcryptic nature of the insect made peopleless than confident in dealing with it.

However, dialogue with colleaguesworking on gorse biocontrol in Hawaiisuggested that the British thrips was a bit ofa non-starter. Hawaii had imported bothBritish and Portuguese strains of S.staphylinus, and while they had also foundthe British strain to be slow-moving orworse, the Portuguese insects dispersedwith encouraging rapidity. For example,one 6000-ha area of gorse was completelyinfested within 6 years.

Portuguese thrips from Hawaii wereimported into quarantine in New Zealand,and were being reared for releases plannedfor early 2002. No one is quite clear whythe Portuguese insects move faster. It maybe that more develop wings… or could it bethat the Portuguese have more of anexplorer's sense of adventure than theirstay-at-home British relatives!

Contact: Hugh Gourlay, Landcare Research,Lincoln, New ZealandEmail: [email protected]

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IPM Systems

This section covers integrated pestmanagement (IPM) including biologicalcontrol, and techniques that are compatiblewith the use of biological control orminimize negative impact on naturalenemies.

More US Apple IPM Success

As a follow up to ‘Apple of their eye’ in thelast issue [BNI 22(4), 81N-83N (December2001)], which described the achievementsof the Areawide Program for Suppressionof Codling Moth in the Western UnitedStates, there is news of more good appleIPM practice from the other side of theUSA.

Fruit Notes Vol. 66 (2001) contains twointeresting articles germane to the ongoingdiscussion of pesticides and the ability ofapple growers to move away from high-riskorganophosphates. Fruit Notes is apublication from the University ofMassachusetts's Fruit Team, whosemission is to assist fruit growers with allaspects of horticultural and pest manage-ment. This is a cooperative programme ofthe research and extension efforts of theDepartments of Plant & Soil Sciences,Microbiology, and Entomology, and is partof the University's Extension's Agro-ecology Program.

Ron Prokopy's article ‘Twenty Years ofApple Production under an EcologicalApproach to Pest Management’, describesthe efforts made on a small commercialfarm to produce apples with largelyecological, prevention-based IPMmethods. The orchard started in 1977. Thearticle presents time-series data on anumber of pests in the orchard, comparinglevels to a nearby unmanaged orchard. Theresults are encouraging; pest damage waskept at or below levels experienced incommercial orchards. Pesticide use wasmuch less frequent and generally involvedsofter materials, because of the emphasis(requirement, actually) to preservebeneficials. This is one of very few articlesthat presents a long-run view of ecologicaladaptation among pests and beneficials in abiointensive IPM orchard. Access thearticle in pdf at:www.umass.edu/fruitadvisor/fruitnotes/twentyyearsof.pdf

A second article in the same issue comparesthe efficacy of insect control when the newreduced risk insecticide indoxacarb(Avaunt) replaces the old, high-risk

material azinphos-methyl (Guthion).Again, the results are encouraging;comparable levels of control wereachieved. The much less severe impact ofindoxacarb on a range of beneficials also islikely to help restore a number ofbiocontrol processes in orchards where hot,broad spectrum organophosphates, carba-mates and pyrethroids are used sparingly ifat all. This article is at:www.umass.edu/fruitadvisor/fruitnotes/comparisonofavaunt.pdf

The careful research behind these articleslends further support to two generalconclusions that most pest managementexperts now embrace, some strongly,others begrudgingly:

• First, prevention-based, bioIPM sys-tems can and are working. Thetechnology and knowledge are therefor those growers with thedetermination and support to make itwork. The reason hard chemical-basedsystems still dominate agriculturalproduction in the USA is thatpesticides are relatively cheap tofarmers and they are easy to use. It isnot that farmers like to handle hotmaterials, or are anti-biology, it isbasically pragmatic. As long as USpolicies remain as they are, pesticide-based systems will remain price-competitive and therefore the commonchoice of most farmers. Almost acrossthe board, high-risk, older pesticidesare the cheapest to use per acre/hectare– to the farmer – since so much of theindirect costs of pesticides are borneby people other than farmers.

• Second, the new generation ofreduced-risk pesticides and bio-pesticides that have been coming onthe market in the last few years areoffering farmers viable alternatives,which can and are serving as steppingstones along the transition to bioIPM.

Website: www.umass.edu/fruitadvisor/

Contact: Wesley Autio, Department ofPlant & Soil Sciences, Bowditch Hall,University of Massachusetts, Amherst, MA01003, USAEmail: [email protected]: +1 413 545 0260

Ronald Prokopy, Department ofEntomology, Fernald Hall, University ofMassachusetts, Amherst, MA 01003, USAEmail: [email protected]: +1 413 545 2115

Congratulations for some really nice,patient work to the apple IPM team at theUniversity of Massachusetts!

By: Charles Benbrook, Benbrook Con-sulting Services, 5085 Upper Pack RiverRoad, Sandpoint, Idaho 83864, USAEmail: [email protected]: +1 208 263 7342

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West African Recipe for Cocoa IPM

Regional collaboration and a participatoryapproach were the key ingredients of ameeting of cocoa scientists held in Benin inlate 2001. It led to the formulation of anoverall concept note for a regional cocoaIPM initiative in West Africa, which willencompass various sub-projects that can besubmitted to various donors. Thisindication of regional commitment tosupport cocoa growers comes as cocoaprices, following years of decline, took anupswing owing to fears over productiondeclines. Falling cocoa production isblamed on recent bad weather and disease,together with the impact of long years ofpoor returns on cocoa growers.

The West Africa Regional Cocoa IPMworkshop held on 13-15 November inCotonou was organized jointly by CABIBioscience and IITA (the InternationalInstitute of Tropical Agriculture). It wassponsored by STCP (the Sustainable TreeCrops Program) and BCCCA (the Biscuit,Cake, Chocolate and ConfectioneryAlliance, UK), and provided scientists fromthe various West African cocoa-producingcountries a platform to exchange ideas.

The BCCCA has a long tradition of supportfor cocoa research and currently funds arange of innovative projects together withkey international resources which willbenefit the world cocoa community. Itsresearch programme aims to achievesustainable production of good qualitycocoa through the development of cost-effective and environmentally responsibleways of controlling the range of pests anddiseases afflicting cocoa production.

The STCP, launched in Ghana in May2000, is a joint public-private partnershipbetween European and American chocolatemanufacturers, bilateral donors (such as theUS Agency for International Development;USAID), NARES (national agriculturalresearch and extension systems) andIARCs (international agricultural research

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centres) in West and Central Africa.Coordinated by IITA, STCP uses a systemsapproach focused principally on thesustainable supply of cocoa, coffee, andcashew nuts through diversified multi-product agroforestry systems. Activitiesunder four programme components(research and technology transfer, growerand business support services, market andinformation systems, and policy) have beenendorsed by a broad coalition ofstakeholders including farmer organiza-tions, marketing agents, industry, researchand extension.

West Africa produces some 60% of theworld's cocoa, and by far the majority ofthis is produced by smallholders, who growit with a number of different crops. At themoment, cocoa production in Africa isfalling. Farmers find it increasinglydifficult to make a living from the crop, inthe face of pest and disease constraints andpoor prices, and are abandoning their trees.The organizers of this workshop, however,described this bleak outlook as a window ofopportunity to steer IPM towards abiologically based system for high qualitycocoa production, in response also to ever-louder calls for environmentally friendlysolutions to pest problems in these areas ofhigh biodiversity where cocoa is grown. Inorder to stem abandonment of the crop, ithas become imperative to rehabilitatecocoa groves and to find new ways to startnew ones in areas where the rainforest hasalready been cut down, and to devise newIPM systems.

The workshop's participants included threecocoa IPM scientists from each STCPmember country (Cameroon, Côte d'Ivoire,Ghana, Guinea-Conakry and Nigeria)together with others from the host countryBenin, CABI Bioscience, CRIG (CocoaResearch Institute of Ghana), NRI (NaturalResources Institute, UK) and IITA. Theworkshop programme was developed inconsultation with the participatingcountries, and provided a platform forscientists to exchange ideas on cocoa IPMresearch and implementation. Each countryoutlined its pest and disease problems, pastand current control measures, and the statusof its cocoa IPM research and implement-ation. Workshop sessions then focused onfinding solutions to common key pestproblems, and options for regional col-laborative research and implementation bypiloting new methods for cocoa extension.

The three key constraints to cocoaproduction in the region were agreed to beblack pod disease caused by Phytophthoraspp., the mirids Distantiella theobroma andSahlbergella singularis, and the cossidmoth stem borer Eulophonotus myrmeleon.

Diseases currently devastating SouthAmerican production (witches' broom,Crinipellis perniciosa, and frosty pod,Moniliophthora roreri) were alsorecognized as looming threats. Interest-ingly, swollen shoot virus (transmittedlargely by mealybugs in the generaPlanococcus and Stictococcus) was, alongwith mistletoes, termites and weeds,considered a threat, but was not accordedthe priority it has sometimes been given.

Three regional groups, with one memberfrom each STCP member country, focusedon one prioritized pest problem. Theyconsidered its current status, available IPMoptions and options in development,identified experts in member countries, andcame up with suggestions for regionalcollaboration to alleviate the problem.Following this, participants came togetheras national groups, and each evaluatedcocoa IPM extension in their country, theexperts they have and how currentmethodology could be improved to reachmore farmers or improve impact.

By synthesizing this information, theworkshop was able to come up with aninventory of on-going and potentialregional cocoa IPM research andimplementation, and a menu of possiblesolutions to the three key pest problems toachieve sustainable and cost-effectivereduction in cocoa yield losses, whilemaintaining good cocoa quality. Corecomponents of the menu are:

• biocontrol using indigenous micro-organisms

• rational pesticide use

• host plant resistance

• cultural controls including habitatmanagement and tree pruning

Strengthening quarantine was added to thislist, to address the need to prevent diseasesfrom other regions of the world gainingaccess to the cocoa-growing areas of WestAfrica.

The next step is to formulate projects andsecure funding to develop and evaluatedifferent methods. The goal is to developsustainable farming systems in the forestzone with cocoa as the main cash crop andfarmers in the driving seat. The solutionshave to be based on what is acceptable tofarmers, and what is needed is a basket ofoptions that alleviate cocoa farmers’ majorpest problems. These should then beevaluated and implemented in 'best-bet'trials using farmer participatory methods.

This will make real the dream of farmersbenefiting from more profitable productionof cocoa using largely biologically-basedIPM. Besides the economic benefits, this

will be better for the health of the farmingcommunity. In addition, such an approachwill sustain the forest environment, evenproviding habitat bridges between forestpockets.

Workshop proceedings will be producedand distributed in 2002.

Contact: Janny Vos, CABI Bioscience UKCentre, Bakeham Lane, Egham, Surrey,TW20 9TY, UKEmail: [email protected]: +44 1491 829100

Peter Neuenschwander, Director, PlantHealth Management Division, IITA, 08 BP0932, Tri Postal, Cotonou, BeninEmail: [email protected]: +229 350556

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PAN Full of IPM Resources

Advice on cocoa IPM can be found in oneof the latest briefings prepared by thePesticides Action Network UK (PAN UK)under the 'Control of pesticides and IPM inDeveloping Countries Project', funded bythe European Commission. One of theproject's outputs, Pest Management Notes(PMN), is a series of four-page briefings forgovernments, development agencies,policy and technical advisers, researchersand others on policies and issues related topesticides and IPM.

Number 12 in the series, 'Sustainable cocoaproduction systems' summarizes major pestand disease problems facing cocoaproducers worldwide, and reviews currentoptions for its sustainable management.Cocoa, it points out, is a crop ofsmallholder farmers, but low prices andhigh input costs have had a major impact onproduction and incomes. In the face offalling prices in this notoriously volatilesector, which have reduced farmers' profitsin many cases to minimal at best, manyfarmers have virtually abandoned theircocoa trees. They have invested the bareminimum of time and inputs, and suchneglect has in turn exacerbated many pestand disease problems. These are legion, butthe conclusions of the workshop describedin the article above mirror some of theconclusions in this Briefing. It identifies themost important pests in West Africa as:black pod disease (caused by Phytophthoraspp.), which causes losses of a staggering44% of global production each year; cocoaswollen shoot virus, transmitted largely bymealybugs (Planococcus and Stictococcusspp.) and leading to losses of some 25%and eventual death of the tree; capsids(Distantiella theobroma and Sahlbergellasingularis), which cause up to 75% loss;


and parasitic mistletoes. The Briefing alsowarns that pests and diseases currentlydevastating cocoa in other parts of theworld loom as threats on the horizon.

Conventional pesticide-based control hasbecome uneconomic and increasinglyineffective. In addition lindane, which hasbeen used to control capsids, is a highlypersistent and toxic insecticide now bannedby many countries. PMN No. 12 outlinescurrent options for sustainable cocoaproduction, including maintaining crophygiene, using resistant varieties, managingshade, biological control, rational pesticideuse and maintaining fertile soils.

The briefing concludes:

• all stakeholders need to be involved ina partnership to develop effectivesustainable systems for cocoaproduction

• apparent farmer reluctance to take upresearch results generally reflectsinappropriate recommendations owingto the failure of research and extensionservices to appreciate farmers'constraints

• participatory approaches build theknowledge and confidence for farmersto make their own crop managementdecisions, and such approaches havealready notched up successes in cocoain Central and South America

PMN is just one output of the first phase ofthis project, which was designed to increasethe speed of implementation of farmerparticipatory IPM and to improve

awareness of essential steps in the soundmanagement of pesticides. The project isimplemented by PAN UK, part of PANEurope, which is one of five regionalcentres coordinating a global networkcomprising over 600 participating non-governmental organizations, institutionsand individuals in over 60 countriesworking to replace the use of hazardouspesticides with ecologically sound alter-natives.

Pesticides continue to be used indeveloping countries, in spite of ofteninappropriate conditions facing women andmen farmers and workers applying theproducts. Policy makers in governmentsand developing countries require accessibleinformation on strategies for improvingcapacity to regulate pesticides, implementbest practice, and develop IPM. PAN UKaims to meet this knowledge gap by makinginformation and resources that promote‘progressive pest management’ widelyavailable. They are drawing on PAN'swide-ranging research of best practice, andon their own and others’ experience ofpesticide regulation and farmer partici-patory IPM strategies. The resourcesproduced are the result of consultations andstudies of needs at both policy and fieldlevel, and will be made available inEnglish, French and Spanish.

In its first phase, the project has produced aguide to reducing pesticide use anddeveloping and implementing IPMpolicies. Comprehensive information andresources have also been gathered and

made available on pesticide hazards andIPM. Profiles provide a snapshot of howsome countries in Africa are progressing inthe transition to safer, more sustainableagriculture, and there is a database ofprojects containing a strong element ofparticipatory IPM. PMN briefings adviseon sustainable management of other majorcrops besides cocoa (coffee, cotton andfruit) and pests (locusts), introduce theconcept of IPM, and give practical andregulatory guidance on pesticide issues.Also forthcoming is a report from fieldstudies on 'Progressive pest managementfor food security and the environment'conducted in four countries (Senegal,Benin, Ghana and Ethiopia) in a variety ofcrops (cotton, vegetables, pineapple, andcereal grains and legumes). The findingsfrom these case studies on the problems andcosts associated with pesticide dependencewill be shared with stakeholders and policymakers in Africa and Europe in order todevelop recommendations for policy andfield-level actions.

Information: www.pan-uk.org/Internat/IPMinDC/ipmindex.htm

Contact: Barbara Dinham, Director,Pesticide Action Network-UKEurolink Centre, 49 Effra Road, LondonSW2 1BZ, UKEmail: [email protected]: +44 20 7274 9084

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Training News

In this section we welcome all yourexperiences in working directly with theend-users of arthropod and microbialbiocontrol agents or in educationalactivities on natural enemies aimed atstudents, farmers, extension staff orpolicymakers.

Community Involvement Underpins Biocontrol in Australia

The South African plant bridal creeper,Asparagus asparagoides, has made animpact in Australia and is listed as one ofthe twenty Weeds of National Significance.It was deliberately introduced in the mid1800s owing to its popularity in bridalbouquets, and with the help of birds eatingits berries and spreading its seeds, it is nowslowly smothering its way across southernAustralia. In severe infestations the foliagesmothers all vegetation to a height of 2-3m.

However, above-ground parts form only afraction of the plant: the vast majority ishidden underground in the form of tubers.Its marked impact is being felt severelythroughout numerous national parks and insome cases it is threatening the existence ofAustralian native species.

Bridal creeper is now a target of twobiological control agents that have beenintroduced, by the Cooperative ResearchCentre (CRC) for Australian WeedManagement and CSIRO Entomology, inan attempt to bring it under control. Thefirst, a leafhopper, Zygina sp, was releasedin July 1999. [See also BNI 20(4) 108N-109N (December 1999) ‘Green giant’.] Itsmost dramatic impact has been seen inWestern Australia (WA) where large areasof bridal creeper have turned white throughthe insect’s sucking activity. Similar resultsare also being found in South Australia(SA) and New South Wales (NSW).

WA is also the site where thousands ofschoolchildren have embraced thisbiological process, rearing and distributingas many insects as possible under theguidance of Technical Officer Ms KathrynBatchelor and project leader Mr TimWoodburn. The results have beenoverwhelming. By the end of 2000 over 40schools and community groups hadbecome involved in the campaign in WAand by the end of 2001 the numbers hadclimbed to more than one hundred.

The attack from the leafhoppers preventsthe plant from photosynthesizing andcauses it to gradually use its stored energyfrom the tubers, making them shrink. Thecontinued shrinking of the tubers will givenative plant seeds a greater opportunity forgermination and establishment than iscurrently the case.

There are numerous generations of theleafhopper every year and this gives the

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insect the ability to build up numbersrapidly. However, more than one biologicalcontrol agent is required and in July 2000the rust fungus, Puccinia myrsiphylli, wasreleased. The rust completes its life cycleon bridal creeper, infecting the leaves andstems. It obtains nutrients and water fromthe plant thus limiting resources availablefor the production of stems, fruit and tubers.

The fungus also destroys leaf tissue byreducing the photosynthetic surface of theplant, causing severely diseased plants toshed infected leaves prematurely. In thewinter rainfall regions of South Africa, therust is usually observed within 12 weeks ofappearance of new shoots in autumn. Fromthen on, the incidence of the rust steadilyincreases during winter to reach its peak inspring when the plants are flowering andfruiting.

Weed CRC/CSIRO pathologist Dr LouiseMorin is in charge of the pathology workand has praised the efforts of communitygroups so far, all of which have had a bigrole to play with the distribution of both theleafhopper and the fungus. The importanceof this role is only going to increase in thefuture.

CSIRO has recently received funding fromthe Natural Heritage Trust which will allowmore community groups to get on board theredistribution process and help release andspread these agents across bridal creeperinfested sites in a much more rapid and

coordinated manner. The funding willallow these groups to be trained by CSIROstaff to develop the basic skills andunderstanding they will require. It will alsoallow for the development of releaseinformation kits outlining the processes,maintenance of a national database onrelease sites and further enhancement of thebridal creeper website (see below).

As well as the work being undertaken byKathryn Batchelor, the Weed CRC’s MrAnthony Swirepik has been the NationalRedistribution Coordinator for biologicalcontrol agents for the last 6 years and has amajor role to play in this project.Swirepik’s job will involve making furthercontact with appropriate groups, organizingbiological agents for them to release,liaising with them to ensure all is goingwell, and determining the level ofmonitoring that is required. The monitoringwill allow researchers to determine howquickly the agents are spreading and whatother areas need to have releases made toensure rapid coverage of bridal creeperinfestations.

Control of massive environmental weedssuch as bridal creeper can only be achievedwith community support. Since the late1980s CSIRO has been developing closerelationships with groups that have anactive interest in biological control. Fromhumble beginnings, national programmeshave now been developed and the future of

some target weeds is looking bleak. This isa situation that could not have beenachieved without the efforts of thecommunity and the state departments thathave been involved.

There remains one more agent to bereleased against bridal creeper, the leaf-beetle Crioceris sp., and an application forits release is now being assessed byregulatory authorities. Both adults andlarvae of this beetle feed on the youngshoots and leaves of bridal creeper. It hasone generation a year and is active duringthe autumn and early winter months whenbridal creeper is commencing its rapidgrowth stage. All three biocontrol agentsco-exist on the plant in its native SouthAfrica, hence researchers anticipate that theaction of these three agents will combine tobring around the future demise of bridalcreeper.

Groups interested in the bridal creeperresearch programme are encouraged tocheck out the web site at:www.ento.csiro.au/bridalcreeper


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AnnouncementsAre you producing a newsletter, holding ameeting, running an organization orrearing a natural enemy that you wantother biocontrol workers to know about?Send us the details and we will announce itin BNI.

BCPC Conference

This annual, international conferenceorganized by the British Crop ProtectionCouncil (BCPC) for the global cropprotection industry will be held inBrighton, UK on 18-21 November 2002,and this year focuses on pests and diseases.

Always a feature of this Conference is thepresentation of new compounds andstrategies for pest and disease managementin temperate and tropical crops. Specialistsessions will examine key strategic topicsthat will influence the management of pestsand diseases in the future with an emphasison meeting expected challenges, includingthose faced in ICM (Integrated CropManagement) and organic farming and byuse of biological control agents.

Website: www.bcpc.org/

Contact: Brighton Conference Secretariat,5 Maidstone Buildings Mews, Bankside,London SE1 1GN, UKEmail: [email protected]: +44 20 7940 5577

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Reason to Consider GMOs

Partisan arguments over GMOs (genetic-ally modified organisms) and theirenvironmental effects continue to behighlighted in the world’s media. Rationaldebate is going on, however, although thatrarely makes headlines. Following on fromour announcement of the IOBC Conferencein Montpellier in November [see BNIDecember 2001], here are two moremeetings this autumn on related themes.

GMO Biosafety Symposium

The International Symposia on theBiosafety of Genetically Modified Organ-isms (GMOs) have been held biennially, to

address the scientific basis for biosafetyissues associated with GMOs (includingenvironmental, as well as human andanimal health concerns). The Symposiumseries is designed for senior scientists,policy makers, regulators, environ-mentalists and industry representativesinvolved in the commercial release ofGMOs. The 7th Symposium will be held on10-14 October 2002 in Beijing, China,under the responsibility of the newly-founded International Society for BiosafetyResearch.

Sessions will focus on diverse issues,including

• New science for enhanced biosafety(chaired by Dr Joachim Schiemann)

• Consequences of gene flow (Dr AllisonSnow)

• Why regulate and how (Prof. JulianKinderlerer)

• Pest control and biosafety (Dr MarjorieHoy)


Contact: Professor Hongya Gu, College ofLife Sciences, Peking University, Beijing100871, ChinaEmail: [email protected]: +86 10 62751841 / 62751194

Ecological Dimensions of GMOs

An international conference is beingorganized jointly by the UK Association ofApplied Biologists and the RoyalEntomological Society to discuss theecological dimensions of GMOs. This willbe held in Reading University, UK on 9-11September 2002.

Sessions will be organized on the themes:

• Gene flow and its consequences

• Impact of GMOs at the crop ecosystemlevel

• Soil and soil processes

Website:www.aab.org.uk/meetings/mtgs2002/gmos.htm

Contact: Carol MillmanEmail: [email protected]: +44 1789 470 234

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Biocontrol in California

The 3rd California Conference on Bio-logical Control (CCBC) will be held on 15-16 August 2002 at the University ofCalifornia (UC), Davis, providing anopportunity to review the latest informationon biological control and its application forpest management in California. Sessionswill cover:

• Transgenic crops and their compati-bility with biological control agentsand other non-target organisms (Mod-erator: Brian Federici, UC Riverside)

• Invasion biology and lessons forbiological control (Les Ehler, UCDavis & Michael Pitcairn, CaliforniaDepartment of Food and Agriculture)

• Biological control of invasive speciesin California (Mark Hoddle UC River-side & Ray Carruthers US Departmentof Agriculture – Agricultural ResearchService, Albany)

• Reduced risk pesticides and compati-bility with biological control agents(Nick Mills, UC Berkeley)

Conference information:www.biocontrol.ucr.edu/

Or contact: Mark S. Hoddle, Department ofEntomology, University of California,Riverside, CA 92521, USAEmail: [email protected]: +1 909 787 3086

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IPPC in China

The 15th International Plant ProtectionCongress (IPPC) will be held in Beijing,China on 6-11 July, 2003, sponsored by theInternational Association for the PlantProtection Sciences and organized by:China Society of Plant Protection.

The 15th IPPC will focus on currentprogress in plant protection sciences andtechnology, and its foreseeable develop-ment in the 21st century. To meet the newchallenge facing plant protection in the newmillennium, the tentative theme of theCongress is ‘The First Great Gathering forPlant Protection in 21st Century’. Topicscovered will include:

• Extension of IPM strategy in the 21stcentury

• Resistance of crops to pests

• Biocontrol

• Chemical pesticides (new products,application techniques, resistance,pesticide management, etc.)

• Biotechnology for plant protection

• Plant protection and the environment

• Information technology in plantprotection and pest prediction

• Ecological regulation and control offarmland pests

• Plant quarantine

• Relationships and coevolution ofcrops, pests and natural enemies

• Non-chemical pest control techniques

Pest management will also be consideredby system, i.e.: grain crops, commercialcrops, orchards, forests, vegetable crops,grassland, flowers and lawns, farmland,pre-planting and postharvest, and forfarmland rodents.

Conference information:www.ipmchina.net/

Or contact: Ms Wen Liping, Secretariat,15th IPPC, C/O Institute of Plant Pro-tection, Chinese Academy of AgriculturalSciences, Beijing 100094 ChinaEmail: [email protected]: +86 10 62815913

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African Insect Science

The 15th Biennial Meeting and ScientificConference of the African Association ofInsect Scientists (AAIS) will be held inNairobi, Kenya on 11-14 June 2003, inpartnership with the Entomological Societyof Kenya (ESK). The conference coincideswith AAIS Silver Jubilee (25thAnniversary) celebration.

The theme of the 15th Biennial Meetingwill be ‘Integrated Pest (IPM) and VectorsManagement (IVM) on African Rural andUrban Livelihoods: Perspective and FutureStrategies’. Subthemes will be:

• Impact of IPM on food and horti-cultural crops production/productivity

• Impact of IVM on human, animal andplant health

• Capacity building, collaboration andnetworking

• Environment, biodiversity and naturalresource management

• Advances in biotechnology and bio-safety

• Conducive policy environment forIPM: modalities and content

Contact: The Hon. Secretary, AAIS, DrFrancis E. Nwilene, West Africa RiceDevelopment Association, 01 BP 2551,Bouaké 01, Côte d’IvoireEmail:[email protected] / [email protected]

Local Organizing Committee (LOC):Entomological Society of Kenya (ESK),PO Box 76662, Nairobi, Kenya

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IOBC Made Easy

IOBC (the International Organization forBiological Control of Noxious Animals andPlants) has a revamped website at:www.oilb.agropolis.fr/

IOBC was established in 1956 as a globalorganization and promotes environ-mentally safe methods of pest and diseasecontrol. As a voluntary organization ofbiological control workers, it givesindividuals and organizations the oppor-tunity to participate in biological controlactivities beyond their specific jobs andworkplaces, to step outside theirbureaucracies, and to contribute to thepromotion of biological control worldwide.IOBC has developed a structure basedprimarily on a regional basis, but withanother (working group) layer defined bytopic, to meet these challenges. Currentlythere are six Regional Sections and tenGlobal Working Groups. Informationdissemination is not easy in such adevolved structure – yet good com-munication is key to IOBC achieving itsaims.

The new site overcomes some of thehurdles. Easily navigable links betweenregions and working groups, with contactdetails, websites and newsletters, allowvisitors quickly to gain an overview IOBC'sinterests, and for biocontrol workers in one

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(geographical or topical) area to keep up todate with other activities and interests ofmembers.

Contact: André Gassmann, CABI Bio-science Switzerland Centre, CH-2800Delémont, SwitzerlandEmail: [email protected]: +41 32 4214871

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Linking African IPM Practitioners

The new Africa Link website is live at:www.ag.vt.edu/ailand in French at:www.ag.vt.edu/ail/french/index.htm

The website has been developed by theAfrica Integrated Pest Management (IPM)Link, a project of the IPM CollaborativeResearch Support Program (IPM CRSP),managed by the Office of InternationalResearch and Development (OIRD) ofVirginia Tech in Blacksburg, Virginia,USA with funding from two US Agencyfor International Development (USAID)units (the Bureau for Africa, and the Officeof Sustainable Development).

The website is the latest venture of theproject, which is fostering the developmentof a network of IPM practitioners in sub-Saharan Africa by facilitating access to thelatest electronic communication and infor-mation exchange tools, in collaborationwith AfricaLink (a USAID initiative), andwith the Consortium for International CropProtection (CICP).

The AFRIK-IPM listserv has beenoperating as an electronic forum fornetworking and information sharingbetween Integrated Pest Management(IPM) professionals throughout sub-Saharan Africa since March 1998, when itwas set up for participants of the IPMCommunications Workshop for Eastern/Southern Africa, held at the InternationalCenter for Insect Physiology and Ecology(ICIPE) in Nairobi, Kenya. Since then ithas continued to serve individuals insideand outside the African continent with aninterest in promoting IPM research andinformation dissemination for sub-SaharanAfrica.

Contact: Miriam Rich, Office ofInternational Research, and Development,1060 Litton Reaves Hall (0334), VirginiaTech, Blacksburg, VA 24060-0334, USAEmail: [email protected]: +1 540 2316741Website: www.ord.vt.edu

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Good Ideas from the Global IPM Facility

The legendary efficiency of the African‘bush telegraph’ as an informationdissemination system has been broughtbang up to date by the Global IPM Facility.

eWAZO (from ‘wazo’, Kiswahili for‘idea’) is a new bi-monthly news service toprovide information from IPM programmedevelopment activities focusing on IPMpolicy, education, and research at regional,country and local levels. Launched inJanuary 2002 by the Global IPM Facilityfrom their office in the UN Food andAgriculture Organization (FAO) head-quarters in Rome, it will be edited by KevinGallagher:Email: [email protected].

To subscribe to this free service, contactM.E. TagliatiEmail: [email protected]

Also keep an eye on the revamped GlobalIPM Facility website, available in English,French and Spanish at:www.fao.org/globalipmfacility/

Although still under development, thislooks set to provide a wide range ofinformation about the Facility, its co-sponsors and donors and other internationalIPM-related information. Already availableis useful information on its operations,which includes pages describing fieldactivities throughout the world.

Text-only and full versions of the completesite, to cater for all needs, set a goodexample that others could follow!

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New Whitefly Website

After 3 years of being hosted by the JohnInnes Centre in Norwich, UK, a newEWSN (European Whitefly StudiesNetwork) website is now live at:www.whitefly.org

The site is designed to provide rapid accessto a wide range of whitefly-relatedinformation, including EWSN members'expertise and publications, EWSNactivities including meetings, sponsors andpartners (with links to websites) and theEWSN newsletters. Coming on-line arelinks to databases to allow access todetailed information on whitefly species,whitefly-transmitted viruses, naturalenemies and control strategies, togetherwith a facility for submitting newinformation and asking questions.

Contact: EWSN Research Facilitator,Department of Disease and Stress Biology,John Innes Centre, Norwich Research Park,

Colney Lane, Norwich NR4 7UH, UKEmail: [email protected]: +44 1603 450045

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Rice IPM CD

RiceIPM is a new interactive informationand identification system released inNovember 2001 by the Centre for PestInformation Technology and Transfer(CPITT) and IRRI (the International RiceResearch Institute), who have developed itjointly, with the help of an internationalteam of IPM specialists from SoutheastAsia. CPITT, part of the University ofQueensland, Australia, develops innovativetools for training and decision support,which are currently being used in more than25 countries.

The new CD is structured according to thecompetency standards required forproficient IPM and thus aims to provideextension officers, researchers, studentsand farmers with a user-friendly andcomprehensive source of information andtraining materials for improving manage-ment of pests in tropical rice.

The new CD uses a range of techniques,including video, images, hypertext linksand interactive keys, to cover pest ecology;crop checking; major insect pests, rats,diseases, weeds, nutrient deficiency andtoxicity; crop growth and pest damage; pestmanagement options and decision-makingand economics. A separate section providesmaterial for researchers and advisers onvarious aspects of implementing IPM,including Farmer Field Schools, multi-media campaigns, and stakeholderworkshops.

Information:www.cpitt.uq.edu.au/software/riceipm/

Obtainable from: CPS-Marketing andDistribution Unit, IRRI, DAPO Box 7777,Metro Manila, PhilippinesEmail:[email protected] / [email protected]: +63 2 761 2404 / + 63 2 761 2406Webpage:www.irri.org/pubcat2000/newtitles.htm#IPMCDPrice: US$5 to developing countries /US$35 to developed countries

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Conference Reports

Have you held or attended a meeting thatyou want other biocontrol workers to knowabout? Send us a report and we will includeit in BNI.

Arthropod Biocontrol Meeting HI-lights

The First International Symposium onBiological Control of Arthropods (1stISBCA) was held on 14-18 January 2002 inHonolulu, Hawaii, USA, and attended by150 scientists from 25 countries. Thismeeting launched a new series of meetingsthat will be held every four years. The goalof the meeting was to bring togetherscientists working on the use of predatorsor parasitoids for control of insects or mitesto discuss projects and issues. The formatof the meeting is small (about 200 keypeople) with no concurrent sessions andplenty of time for discussion.

Introduction, augmentation and conser-vation biological control were each coveredby a full day of 16 talks each, with theopening day devoted to consideration ofissues and methodologies affectingbiological control projects broadly. Themeeting series is conceived to be theanalogue of the long running and highlyeffective International Symposia on theBiological Control of Weeds, which havebeen going since 1960. The new ISBCA isintended to bring together people workingon control of insects and mites to fostercommunication and stimulate work onissues of common interest.

The first day of the meeting (Monday) wasopened by a keynote address from MarkHoddle of the University of California anda special talk by Jim Cullen of Australia(CSIRO) honoring Doug Waterhouse,recently deceased. The first session, 'Issuesin Future Expanded Use of ClassicalBiological Control', was opened byMatthew Cock of CABI Bioscience,followed by Lloyd Loope of the USNational Park Service, Frank Howarth ofthe Bishop Museum, Barbara Barratt ofAgResearch in New Zealand, and DonSands of CSIRO in Australia. Issuesdiscussed included perspectives on therising tide of invasions in an age of globaltrade, legal issues in the regulation ofbiological control, and technology forestimating host ranges of new parasitoidspecies being studied for introduction. Thesecond session of the day, 'Methods toColonize, Evaluate, and Monitor NaturalEnemies', presented material on studies ofnative whitefly host relationships in

Australia, introduced whitefly parasitoidsin the US, and the successful control of aeucalyptus borer in California. Theafternoon programme continued with asession, 'Use of Molecular Methods inClassical Biological Control', organized byMarjorie Hoy of the University of Florida,which featured case studies on how to usemolecular methods to do such things asseparate out cryptic species in naturalenemy collections, exclude contaminatingpathogens in groups of natural enemies inquarantine, and obtain field estimates ofpredation and parasitism. This session wasfollowed by 'Modeling and Theory as Toolsto Clarify Causes of Success or Failure ofBC Projects', organized by Nigel Barlow ofAgResearch in New Zealand, withpresentations by scientists from California,France, and the Czech Republic.

Tuesday was devoted to studies ofbiological control through augmentation ofnatural enemies. The keynote speaker forthe day was Kevin Heinz of Texas A & MUniversity (USA). Two sessions focusedon crop-specific examples: 'Successes inAugmentative Biological Control', whichcovered use in greenhouses and apples and'Survey of Actual and Potential Use inOutdoor Crops', organized by Bob Luck ofthe University of California, USA, on useof augmentative biological control in citrusand hops. The other two sessions coveredeconomics of natural enemy production('Economics of Production and use ofReared Natural Enemies', organized byRon Valentin, Koppert, Canada, Inc.) fromthe producer’s perspective and the ecologyof natural enemy movement ('Post-ReleaseDispersal, Distribution, and Impact ofAugmented Natural Enemies in FieldSettings', organized by Livy Williams, USDepartment of Agriculture; USDA).

The middle day of the programme wasdevoted to a tour of the Island of Oahu, withstops to see natural enemy research onmites on papaya and mealybugs onpineapple, and also stops at the StateDepartment of Agriculture and the USDAfruit fly research laboratory.

Thursday was devoted to studies ofbiological control by means of naturalenemy conservation. The keynote speakerwas H. F. van Emden of ReadingUniversity, UK. Sessions were presentedon 'Nectar Feeding by Parasitoids'(organized by George Heimpel ofMinnesota, USA and Robert Pfannensteil,Texas, USA), featuring speakers fromAustralia, New Zealand, and the

Netherlands; on 'Alternative Hosts andHabitat Refuges for Natural Enemies'(same organizers); on 'Effects on NaturalEnemies of Using Bt Crops in IPMSystems' (organized by Brian Federici,University of California, Riverside); and'Pesticide Effects on Natural Enemies'(organized by Livy Williams, USDA).

The final day of the programme (Friday)was given over to recent projects ofclassical biological control. Tom Bellows,University of California, Riverside waskeynote speaker and speakers addressedprojects from Benin, Guam, Papua NewGuinea, Australia (Queensland), NewZealand, the USA (Florida and California),Japan and Switzerland. In addition, therewas a session organized by RussellMessing of the University of Hawaii'Monitoring for Effects of BiocontrolAgents on Nontarget Organisms'.

The proceedings of the meeting (shortpapers of all 147 presentations – 66 talksand 65 posters) will be published withsupport of the US Forest Service and freecopies will be available by late summer2002 (contact Roy Van Driesche forcopies).

The next meeting in this series will be heldin late September-early October, 2005 inSwitzerland in the high Alps. UlliKuhlmann, CABI Bioscience Switzerland,will put together the local organizingcommittee. An international programmecommittee to develop the meeting's contentwill be headed by Mark Hoddle, Universityof California, Riverside. Anyone interestedin helping on the committee should get intouch with Mark.Email: [email protected]

The long term importance of this series ofmeetings will be in fostering closer contactamong insect biological control workersand providing a forum for discussion ofcritical issues and organizing ad hoc groupsto address them. We hope to haveapproximately 200 of the world’s toppeople in attendance in Switzerland.

By Roy Van Driesche, Department ofEntomology, University of Massachusetts,USAEmail: [email protected]

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Hot Topics in Australasian Plant Pathology

The Australasian Plant Pathology Societywas founded in 1969 and every 2 years anorganizing committee from an AustralianState or Territory or New Zealand hasconvened the APPS conference and held itat a local venue. The 13th BiennialAustralasian Plant Pathology SocietyConference was held in Cairns in northQueensland, Australia on 24-27 September2001. This was the first time the conferencehad been held in a regional location and thefirst time it had been held in a tropicallocation. Around 325 delegates from 20nations attended the conference andpreceding workshops. Delegates camefrom all states of Australia, New Zealand,South Africa, Japan, Papua New Guinea,Fiji, Samoa, Indonesia, Vietnam andThailand. Some delegates travelled fromEurope and the USA to participate in theconference.

The workshops that preceded theconference dealt with a wide range oftopics including:

• Identification and classification ofAscomycetes

• Identification and classification ofUstilaginomycetes

• Uncultivable plant pathogens

• Introduction to Bionavigator

• Soil nematode ecology

• Plant defence mechanisms

• Dieback in tropical rainforests

• Diagnosis of plant diseases caused bybacteria

• Plant pathology diagnostics

The workshop on plant defencemechanisms proved to be the most popularat this year’s conference. The nematodeecology workshop run by Dr Gregor Yeateswas able to use the diversity of nematodesassemblages to demonstrate the impact thatdifferences in agricultural practices have onthe soil ecology. A report on the results ofthis workshop is to be published in theAustralasian Nematology NewsletterDecember publication.

The conference was divided into threesymposium sessions, 25 concurrentsessions and eight poster sessions.

The first symposium on PathogenDynamics in the Plant Environment dealtwith genetics and genomics of fungalpathogenicity (Dr Richard Oliver), cellularinteractions of biotrophic fungal pathogens(Dr Michelle Heath) and microbial ecologyin the rhizosphere (Dr Dan Kluepfel). Thesecond symposium, focussing on getting

the message out, dealt with relayinginformation to farmers about plant diseasesand the importance of two-way com-munication when dealing with complexissues such as plant diseases (Dr Joe Noling& Dr Joe Kochman). An account of whatfarmers are faced with was given by MrAlan Zappala who manages a mixedfarming enterprise which includessugarcane, tropical fruit and flowerproduction. The final symposium dealtwith plant pathology in the tropics. The pestand disease situation of sugarcaneproduction in Papua New Guinea, the homeof sugarcane, was highlighted by Dr LastusKuniata. The need for quality biodiversitythrough resistance breeding and use of wildtypes was presented by Dr Jill Lenne. Thediagnostic and advisory support needed indeveloping countries to deal with plantdiseases was highlighted by Dr MarkHolderness.

Two additional keynote addresses weregiven by prominent international delegateson fungal population genetics (Dr BruceMcDonald) and on virus vector relation-ships (Dr Tom Pirone). The presidentiallecture (Dr David Guest) and the McAlpineMemorial Lecture (Dr Alan Dubé) bothhighlighted the difficulty in funding plantpathology research, an analysis of externalfactors influencing research and employ-ment of plant pathologists as well as theneed for succession planning to ensure highquality plant pathology research continuesin Australasia.

There were 141 oral presentations and 159poster presentation at the conference. Theconcurrent oral and poster sessions werecategorized into extremely diverse subjectgroups. Oral session topics were soil bornediseases, exotic pathogens and quarantine,disease surveys and new pathogens (twosessions), biological control of weeds,virology (two sessions), bacteriology, plantpathogen interactions (two sessions), popu-lation genetics of pathogens, epidemiology,diagnosis and detection (two sessions),phytoplasmology, disease management(three sessions), nematology, breeding fordisease resistance, biocontrol of pathogens,diseases in natural ecosystems, inducedresistance, and tropical plant pathology(two sessions). Contributed posters weredivided into suitable topic groupings andeach poster presenter was given a shortperiod of time, in designated posterdiscussion sessions, to informally present abrief overview of their work to interestedlisteners. Poster discussion session topicswere detection and diagnosis, diseasemanagement, nematology/bacteriology/phytoplasmology/virology/diseases of un-certain etiology, fungal diseases (two

sessions), breeding for disease resistance,disease and weed management, and hostpathogen interactions.

Following the conference, two busloads ofdelegates were given a chance to see firsthand, Australian tropical agriculture andhorticulture in action. As always, thismeeting facilitated ample social interactionand informal networking. A welcomemixer and the formal dinner took place atthe Cairns Convention Centre. A farewellfunction was held poolside at a nearbyhotel.

The 14th Australasian Plant PathologySociety Conference is to be held inconjunction with the 8th InternationalCongress of Plant Pathology in Christ-church, New Zealand on 2-7 February 2003at the Christchurch Convention Centre.Information on the conference can beaccessed at their website:www.lincoln.ac.nz/icpp2003

By: Tony Pattison, Queensland Depart-ment of Primary Industries, Centre for WetTropics Agriculture, PO Box 20, SouthJohnstone, Qld 4859, AustraliaEmail: [email protected]: +61 7 4064 2249

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Weed Biocontrol in Europe

The latest weed biological controlworkshop of the European Weed ResearchSociety (EWRS) was held in the School ofPlant Sciences, the University of Reading,Reading, UK on 6-7 January 2002 and wasattended by 28 delegates from eightcountries. These workshops are run by theBiological Control Working Group of theEWRS and are held roughly every 2 years(recent ones have been held in Switzerland,Germany and France). They aim to providean informal forum for the discussion ofcurrent research and weed biologicalcontrol issues in Europe.

Dick Shaw (UK) started proceedings bydiscussing the challenges facing classicalbiological control of weeds in the UK.Despite much experience with natural pestcontrol there has never been a full release ofa weed biological control agent in Europe:a successful example would greatly helpfacilitate the further development of thisfield. Heinz Müller-Schärer (Switzerland)then described the genetic populationstructure of Senecio vulgaris in relation toits pathogen Puccinia lagenophorae.Despite significant within and betweenpopulation genetic variation in sus-ceptibility to the rust fungus, sustainabilityof biological control was estimated as highas no incompatible reactions were


observed. Blair Grace (Switzerland)followed and reported that placing inoculaof P. lagenophorae in the field early in thegrowing season can make S. vulgaris lesscompetitive against carrots, thus increasingtheir marketable yield. This could be apromising example of the systemsmanagement approach.

Jonathan Gressel (Israel) described recentwork in obtaining hypovirulence againstAbutilon in Colletotrichum coccodes afterintroducing the nep 1 gene. He then talkedabout a proposed system for 'bio-barcodingTM' mycoherbicides to mark andprotect transgenic and/or patented lines, orto trace mycoherbicides in theenvironment. This was followed by fourpapers exploring different aspects ofherbivore interactions with weeds. AloisHonek (Czech Republic) described thedevelopment of two Coleoptera seedpredators of Taraxacum officinale inrelation to their temperature requirements,Esther Gerber (Switzerland) reported onexperiments into the effect of the rootherbivore Ceutorhynchus scrobicollis onthe invasive weed Alliaria petiolata, anenvironmental weed in North America, IanKeary (UK) reported on experimentsdetermining the effects of insects and fungi,applied alone and in combination, on theestablishment of Rumex obtusifolius inLolium perenne, and Urs Treier (Switzer-land) explained the effect of cattle andmollusc grazing on seedling recruitment of

the mountain grassland weed Veratrumalbum.

The second day of the workshop startedwith a paper by Alan Gange (UK)describing the results of some novelexperiments investigating the potential forbiological control of Poa annua in sportsturf using mycorrhiza which appear to beantagonistic to this weed. This wasfollowed by three papers reportingexperiments into biocontrol of Orobancheusing fungi. Dorette Müller-Stöver(Germany) described successful green-house trials of a granular formulation ofFusarium oxysporum f. sp. orthocerasagainst O. cumana. However, the level ofthe disease and its influence againstOrobanche emergence was far lower in thefield compared to the pot experiments.Joseph Hershenhorn (Israel) detailedseveral new pathogens against Orobanchethat were being tested in the greenhouseand Jonathan Gressel (Israel) gave a talk onwork in his lab on engineeringhypervirulence in F. oxysporum and F.arthrosporioides pathogenic on O.aegyptiaca using genes that causeoverproduction of IAA.

In addition, posters were displayed onallelopathic compounds from Inula viscosa(Joseph Hershenhorn, Israel), the potentialof biological control as a management toolfor Rhododendron in the UK (MarionSeier, UK), progress on the Japaneseknotweed biological control programme in

the UK (Dick Shaw, UK), and the insectnatural enemies of Cuscuta and Orobanchein Slovakia (Peter Toth, Slovakia).

The workshop finished with a guided visitto CABI Bioscience's Ascot weedbiological control laboratories. The paperspresented at the workshop demonstratedthat research into the biological control ofweeds in Europe is still strong, with a greatdiversity of target systems and biocontrolapproaches being investigated. It isespecially healthy that new approaches arealso being actively investigated. However,bearing in mind the opening presentation,there was a discussion session during theworkshop on ideas for improving thevisibility of weed biological control and theworking group in Europe. It was decidedthat as a first step a web-site would be set upto provide a forum for exchange of ideasand information.

The next working group meeting will beheld in conjunction with the EWRSsymposium in 2004.

For an email copy of the abstracts from thisworkshop, or to be placed on the (e)mailinglist, please contact the working groupchairman (Email: [email protected]).

By Paul Hatcher, University of Reading,UK

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New Books

Beautifully Moth-Eaten

This book* is a welcome second volume inan ACIAR (Australian Centre forInternational Agricultural Research) serieson using arthropod agents for biologicalcontrol of water hyacinth (Eichhorniacrassipes). Happily, like its predecessor, itis as useful and authoritative as it is good tolook at, and provides a complete 'do-it-yourself' guide to the use of twolepidopteran biological control agentsusing the CSIRO methods that have beensuccessfully employed in manyprogrammes.

The first volume** in the series dealt withNeochetina weevils; this second volumedeals with the moths Niphograptaalbiguttalis and Xubida infusellus. Bothbooks include introductory sections on thebiology and impact of water hyacinth,together with options for its management,and then go on to deal with the agents andtheir use in biological or integrated control.

This book describes the biologies and hostranges of the moths, gives a history of theirintroductions and a comprehensivesummary of host specificity testing. Theoutstanding feature once again, however, isthe clearly written, highly illustratedsections on rearing, releasing andmonitoring techniques for those who wantto use the moths for biological or integratedcontrol of water hyacinth.

*Julien, M.H.; Griffiths, M.W.; Stanley,J.N (2001) Biological control of waterhyacinth 2. The moths Niphograptaalbiguttalis and Xubida infusellus:biologies, host ranges, and rearing,releasing and monitoring techniques forbiological control of Eichhornia crassipes.ACIAR Monograph Series No. 79, 91 pp.ISBN 1 86320 295 1

**Julien, M.H.; Griffiths, M.W.; Wright,A.D. (1999) Biological control of waterhyacinth. The weevils Neochetina bruchiand N. eichhorniae: biologies, host ranges,

and rearing, releasing and monitoringtechniques for biological control ofEichhornia crassipes. ACIAR MonographSeries No. 60, 87 pp. ISBN 1 86320 267 6

Obtainable from: ACIAR, GPO Box 1571,Canberra, ACT 2601, Australia.

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South African Weed Handbooks

Two useful handbooks in relation to ‘NewLegislation Benefits Weed Biocontrol inSouth Africa’ (see General News, thisissue) are described here.

Declared Weeds and Invasive Plants inSouth Africa

The main objective in producing thishandbook* was to enable members of thepublic and the relevant authorities toidentify the declared weeds and invaderscovered by the Conservation of

News 23N

Agricultural Resources Act, 1983 (Act 43of 1983) (CARA), as amended duringMarch 2001. It is the officially recognizedguide to the plant species banned orregulated by the amended CARAregulations, sanctioned by a foreword bythe Minister for Agriculture and LandAffairs.

Even dedicated environmentalists despairat the task of learning to recognize thealmost 200 plant species on the list,remembering to which category eachbelongs and learning how to deal with eachcategory. Several over-zealous gardenersand land managers have acted on rumours,mistakenly destroying indigenous trees orspecies not mentioned in the CARAregulations.

The new book should put an end to theuncertainty and rumours amongstgardeners, horticulturists, foresters andagriculturists about which plants may stay,which ones have to be removed, whichones may no longer be sold and which onesmay only grow in demarcated areas. In thewords of the Minister for Agriculture andLand Affairs “It is a guide that is longoverdue, and will provide for a systematicand sustainable assault on invasive alienplants”.

Some of the features of the new book are:

• descriptions, distribution maps and linedrawings of 234 species of alien weedsand invasive plants in South Africa(including some species that have beenproposed for legislation but have notyet made it into the CARA list)

• all 198 species of declared weeds andinvaders, and a complete copy of theregulations concerning their control

• colour photographs of 100 speciesincluding some of the less familiarones

• a quick guide to the identification ofthe major groups of plants, based on

characteristics that are always visibleand easy to understand

• an indication of whether the plantspecies are subjects of herbicideregistration and biological control, andwhether they are poisonous or irritant

• other sources of information, acomprehensive glossary and an indexto botanical and common names

The major sponsors of this publication werethe Department of Water Affairs &Forestry and the National Department ofAgriculture.

Rehabilitation of Areas Cleared of AlienPlants

This handbook**, which includes region-specific ‘GRAB-A-GRASS dials’, is aimedat people who want to clear alien vegetationfrom their land without causing soil erosionor a resurgence of weed seedlings in thecleared areas.

It provides guidelines and recom-mendations for the selection of suitablegrass species, using practical rehabilitationmethods after removal of alien vegetation.Integrated control strategies for alien plantshave been categorized for alien trees,shrubs, succulent species and herbs. Thebook contains colour photographs andeasy-to-follow graphics.

Part 1 of the book deals with the integratedcontrol of alien plants and covers:

• control of standing trees

• how to fell trees and control stumps

• burning strategies

• how to control alien shrub species

• follow-up control methods includingchemical, mechanical and biologicalcontrol

• planning for integrated alien plantcontrol

Summary tables at the end of part 1describe provincial distribution and abun-

dance of the most common alien plants, andthe available mechanical, biological andchemical methods for their control.

Part 2 reports back on five workshops thatwere held to collate the known informationon the selection of grass species forrehabilitation. It introduces suitable grassspecies to cover bare soil after alien plantcontrol, and explains how to select the grassspecies according to land-use aims andenvironmental constraints.

A 'GRAB-A-GRASS dial' provided withthe book is an easy-to-use device composedof three rotating discs. The discs havewindows cut into them, which describe indetail the seven steps to follow when usinggrass to rehabilitate and manage alienplants.

Part 3 describes harvesting methods forgrass species that are not commerciallyavailable, and practical grass plantingmethods that have been tried and testedover many years.

This book also forms part of two alien plantcontrol courses approved through Act 36 of1947 for the registration of Pest ControlOperators.

*Henderson, L. (2001) Alien weeds andinvasive plants: a complete guide to de-clared weeds and invaders in South Africa.Pretoria, South Africa; ARC-PPRI, PPRIHandbook No. 12, 300 pp.

**Campbell, P. (2001) Rehabilitation rec-ommendations after alien plant controlPretoria, South Africa; ARC-PPRI, PPRIHandbook No. 11b, 124 pp.[This book notice is adapted from PlantProtection News No. 59, Summer 2001.]

Available from: Mrs Hannetjie Combrink,the PPRI Librarian, Private Bag X134,Pretoria 0001, South AfricaEmail [email protected]

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Proceedings

Enhancing Biocontrol Agents and Handling Risks

This publication* is the proceedings of aNATO Advanced Research Workshop heldon 9-15 June 2001 in Florence (Italy).Initially it annoyed me immensely. Ideclare a slight prejudice in reviewing thisbook, based on the preface. The firstsentence makes no sense, raising doubtsabout the care taken with the editing, and

throughout the book there are annoying, butunimportant, formatting errors.

Then later in the preface came a paragraphthat was preposterously arrogant anduntrue. "A large proportion (but not all) ofthe major groups intent on enhancingbiocontrol agents attended the workshopand contributed to this volume.” Whatnonsense! There is only one representativefrom sub-Saharan Africa, so what of theInternational Institute of Tropical Agri-

culture in the Republic of Benin, CABInternational Africa Regional Centre andthe International Centre of Insect Pathologyand Ecology (both from Kenya), KawandaAgricultural Research Institute in Ugandaetc., etc. South America and Asia are notrepresented at all. Even from the UK atleast three significant groups were notpresent.

And then: "Some could not attend, leadingto a few gaps in subject matter." Indeed, for


example the use of insects – not unknownas control agents, viruses for insect controlperhaps, something more than a passingmention of mass production. Some mayconsider agricultural management relevant,the ecology of insects, their pathogens andthe environment has recently been shownto be critical and quality control ofbiological pesticides is pivotal etc., etc. Afew gaps in subject matter!

The volume reads (largely but notexclusively) as one for the academic ratherthan the practitioner and there is a strongemphasis on genetic engineering and onpathogens. With a more accurate title andless pomposity in the preface, the bookwould have been easier to evaluatedispassionately. Within the limits ofspeculative and innovative research onenhancing pathogens as biocontrol agentswith an emphasis on genetic engineeringand handling risks, it is a good book withmany interesting chapters. However,despite the comments above about thelimitations of coverage, there is still muchto cover and it is difficult to see who theaudience would be. A specialist is unlikelyto learn much new and the generalist isfaced with very specific examples (oftenused as generalizations). The chapters varyin depth and the very diverse topics meansthat the book lacks continuity, although thisis probably inevitable when dealing withinnovation.

There are 24 chapters, in four sections, plussix one-page abstracts. The first section, onNeeds for Enhanced Biological Agents andStrategies for Enhancement, contains threepapers with an eclectic mix of biocontrolagents against weeds, a geneticallymodified virus for fertility control in rabbitsand the use of microbial toxins.

Technologies of Enhancing BiocontrolAgents contains eight chapters that thesession organisers divide into five groupswith brief descriptions (these sessionsummaries are probably the best way ofgetting the essence of the book). Aspects ofproduction and delivery of pathogens arebriefly covered. Here again titles can bemisleading. What does “Enhancing Bio-logical Control Through SuperiorFormulations: A Worthy Goal But StillWork in Progress” mean? As it turns out, it

is a very interesting and informativechapter on a very specific matter, improvedshelf life of Metarhizium anisopliaeblastospores. Why couldn’t it say that? Butthe section also contains fascinatingchapters on natural phytotoxins for weedmanagement, using genes from biocontrolagents (neither, incidentally, biocontrolagents as per the book title) enhancingbioherbicides by, for example, manipu-lation of the culturing media, andenhancing antagonists of postharvestdiseases.

The remainder of the book consists of fivechapters in Risks from Enhanced Bio-control Agents and their Mitigation, eightin Genetics and Molecular Biology ofEnhancing Biocontrol Agents, and six onepage abstracts. These are outside my area ofexpertise, but a couple could be valuablereference chapters. “Introducing Trans-genic Biocontrol Agents into theEnvironment: Legal, Ethical and PoliticalProblems” is very readable and informativeand the title describes the content.

One very good aspect of the book is theattention paid to references, which areusually very comprehensive. But overall,this is a book that could be occasionallydipped into: one to borrow and not to buy.

*Vurro, M.; Gressel, J.; Butt, T.; Harman,G.E.; Nuss, D.L.; Sands, D.; St. Leger, R.(2000) Enhancing biocontrol agents andhandling risks. Amsterdam, The Nether-lands; IOS Press. NATO Science Series:Life and Behavioural Sciences, Vol. 339,200 pp. Hbk. ISBN 1 58603 216 X. PriceUS$90/€95/UK£60.

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IOBC Water Hyacinth Meeting in Beijing

The proceedings of the 2nd Meeting of theGlobal Working Group for the Biologicaland Integrated Control of Water Hyacinthhave now been published*. Held in Beijing,China under the auspices of theInternational Organization for Biologicaland Integrated Control of Noxious Animalsand Plants (IOBC) in October 2000 [seeBNI 22(1), 16N-17N; March 2001], themeeting brought together 31 delegates from11 countries. It was organized by the

Institute of Biological Control, ChineseAcademy of Agricultural Sciences(CAAS), and supported by the NationalNatural Scientific Foundation of China,CAAS.

The proceedings contain 22 papers,including three keynote presentationswhich review arthropod biological controlof water hyacinth (M. H. Julien);opportunities, challenges and develop-ments in its control by pathogens andmycoherbicides (R. Charudattan); and thecurrent status of research on the weed inChina (Ding Jianqing, Wang Ren, FuWeiding & Zhang Guoliang).

Other papers give a broad coverage of keyissues and challenges in water hyacinthmanagement, and include news of progressmade and obstacles still to be overcomefrom South Africa, Zimbabwe, Malawi,Rwanda, Tanzania, Kenya, Egypt andChina; assessments of research pro-grammes on mycopesticides; weed andnatural enemy ecology; safety and hostspecificity and efficacy testing of naturalenemies; potential new agents – needs andnew exploration; and knowledge dissem-ination initiatives.

The volume includes session summaries,recommendations for future research andthe mission statement developed by theGlobal Working Group at this meeting.

*Julien, M.H.; Hill, M.P.; Center, T.D.(eds) (2001) Biological and integratedcontrol of water hyacinth, Eichhorniacrassipes. Proceedings of the SecondMeeting of the Global Working Group forthe Biological and Integrated Control ofWater Hyacinth, Beijing, China 9-12October 2000. Canberra, Australia; Aus-tralian Centre for International Research,ACIAR Proceedings No. 102, 152 pp.ISBN 1 86320 319 2 (print) / 1 863 20 3206 (electronic)

Printed copies from: ACIAR, GPO Box1571, Canberra, ACT 2610, Australia

Electronic version downloadable from:www.aciar.gov.au/publications/proceedings/102/index.html

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