Book Reviews

The ecology of plants and plantecologists

Gurevitch, J., Scheiner, S. M. & Fox, G. A.

(2002) The ecology of plants. Sinauer

Associates, Sunderland, USA. Xvi þ 523 pp,

figs., tables, line diagrams, halftones,

glossary, index. Hardback: Price $89.95.

ISBN 0-87893-291-7.

What do you want a plant ecology textbook

to do? First, of course, explain the basics.

Secondly, give a balanced account of con-

troversial topics, so that students can see that

there is a disagreement and draw their own

conclusions. Thirdly, although this may be

asking a bit much, cover everything (or nearly

everything) in reasonable detail. Students

cannot be expected to buy too many books at

this sort of price.

Gurevitch, Scheiner and Fox (GSF) have

certainly striven to be comprehensive,

covering everything from the basics of plant

physiology to biomes, palaeoecology and

some elementary meteorology. Most of this is

performed rather well; C3, C4 and CAM and

their ecological consequences, for example,

are explained clearly and concisely. Water

potential is probably explained about as well

as it can be, although how water gets to the top

of tall trees still seems like some kind of con-

juring trick.

The reader is also generally left in little

doubt that a consensus has yet to be reached

on some topics. Do mycorrhizae really move

mineral nutrients (and maybe even carbon)

between plants in the field, and is this eco-

logically significant? Maybe, maybe not. Is

competition more or less intense under pro-

ductive conditions? Plenty of evidence is

presented on both sides, leaving us to make

up our own minds. A plus point here is that

GSF have avoided the usual compulsion to

start with the Lotka–Volterra competition

equations, correctly pointing out that they

simply are not very helpful. A minus is the

time wasted on the thoroughly unhelpful

distinction between competitive effect and

response, because the latter means either

everything or nothing, depending on your

point of view. Attempting to be fair some-

times requires an ability to entertain two

completely incompatible ideas at the same

time. GSF spend quite a lot of effort trying

to explain R*, while elsewhere citing Huston

& De Angelis (1994), which demonstrates

that R* is incompatible with the laws of

physics. The current debate about biodiver-

sity and ecosystem function is fully reported,

although Huston’s (1997) devastating cri-

tique of the recent work on model systems is

not cited.

Another controversial topic is invasions

and invasibility. GSF point out that

ecologists have a miserable record of

predicting invasiveness, without acknowled-

ging that one reason for this may be that it is

impossible. Different habitats are invaded by

very different kinds of plants, and it is no

surprise that where progress has been made,

it is been by concentrating on one narrow

habitat type. In the end, however, invasions

are dealt with rather well; all the main ele-

ments of the fluctuating resource theory of

invasions are described, although Davis

et al. (2000) is not cited.

There are many things to celebrate in this

book: the highlighting in bold, and explan-

ation in a glossary, of any new bit of eco-

logical jargon the first time it appears; a

general scepticism about the closeness of

many so-called mutualisms, e.g. many plants

and their pollinators; the often-overlooked

point that some trade-offs must exist while

others do not necessarily, and that the evi-

dence for some of the latter is very thin

indeed. The reader is being left in no doubt

that very few plants exist as metapopula-

tions. Best of all is a recognition that ecology

did not begin in 1980, as many current un-

dergraduates seem to believe. Even the hoary

old dispute between Clements and Gleason is

described with a new freshness. Clements’

views, although clearly wrong, held sway

until after his death in 1945. Indeed Gleason,

disillusioned by the failure of his views to

make any impact, abandoned ecology and

spent the rest of his career as a taxonomist.

Clements, we are told, had �an extremely

strong personality� (GSF stop short of des-

cribing him as a bully). Whether this story

has a modern moral is left to the reader, but

it should make today’s students think about

who they believe, and why.

However, I have some gripes too. GSF

make the common American mistake of

attributing the intermediate disturbance the-

ory to Connell (Connell, 1978; see also

Wilkinson, 1999), although to be fair, they get

the attribution right later (Grime, 1973) when

they consider the �hump-backed� relationship

between productivity and diversity. The

whole book has a pervasive Americanism: a

map has global mean temperatures in �F;

another figure of the climates of a range of

locations has altitudes in feet and precipita-

tion in inches; a table listing the CO2 gen-

eration of some human activities has a �small

car� with a 1.7 L engine. A lack of awareness

of the world outside North America seems to

be taken for granted: a box begins �You may

never have heard of the fynbos, but…�. Some

seed-related topics are dealt with very super-

ficially. We are not given any real ecological

justification for the existence of persistent soil

seed banks, and almost the whole of the short

section on this topic is devoted to the Beal

seed burial experiment. We are told that both

Salisbury (1942) and Baker (1972) published

classic studies on seed size, but only Baker’s is

described, giving the misleading impression

that large seeds are characteristic of open

habitats. A final word of warning: taxonomy

follows the latest Angiosperm Phylogeny

Group classification, so I am afraid Acer

really is in the Sapindaceae.

A nice touch is pictures of a selection of

famous ecologists. In a welcome attempt to

inspire young female ecologists, several of

these are of women. A few are Brits, and one

is even a (non-British) European, but I am

afraid one is still left with the impression that,

if you are an ecologist and you want to be

famous, it helps to be white, male and

American.

Ken Thompson

Department of Animal andPlant Sciences,

University of Sheffield,UK

E-mail: ken.thompson@sheffield.ac.uk

Journal of Biogeography, 30, 155–157

� 2003 Blackwell Publishing Ltd

REFERENCES

Baker, H.G. (1972) Seed weight in rela-tion to environmental conditions inCalifornia. Ecology, 53, 997–1010.

Connell, J.A. (1978) Diversity in tropicalrain forests and coral reefs. Science,199, 1302–1310.

Davis, M.A., Grime, J.P. & Thompson, K.(2000) Fluctuating resources in plantcommunities: a general theory ofinvasibility. Journal of Ecology, 88,528–534.

Grime, J. (1973) Competitive exclusion inherbaceous vegetation. Nature, 242,344–347.

Huston, M.A. (1997) Hidden treatmentsin ecological experiments: re-evaluatingthe ecosystem function of biodiversity.Oecologia, 110, 449–460.

Huston, M.A. & De Angelis, D.L. (1994)Competition and coexistence – theeffects of resource transport and supplyrates. American Naturalist, 144, 954–977.

Salisbury, E.J. (1942) The reproductivecapacity of plants. G Bell and Sons,London.

Wilkinson, D.M. (1999) The disturbinghistory of intermediate disturbance.Oikos, 84, 145–147.

Complexity underpins plant–pathogen interactions

Jeger, M. J. & Spence, N. J. (eds, for the

British Society for Plant Pathology) (2001)

Biotic interactions in plant–pathogen

associations. CABI Publishing, Wallingford,

UK. Xi þ 353 pp., figs, tables, index.

Hardback: Price £60.00. ISBN 0-85199-

512-8.

The book is a selection of papers from a

joint meeting in December 1999 between the

British Society for Plant Pathology and

the Association of Applied Biologists Vir-

ology Group. The focus of the book is not

on the single agent–single disease approach,

which currently has very high profile at the

molecular level, but on the complex interac-

tions of pathogens and other biotic and abi-

otic components in the environment that

pertains to the more �natural� situation (be

that managed or natural ecosystems).

The authors for each chapter were asked to

address the �genetical, physiological and eco-

logical interactions influencing plant–patho-

gen associations�. Consequently, the message

in the book is clear: �that only once an

understanding of the complexity is gained can

we fully appreciate the significance of biotic

interactions in understanding and manipula-

ting plant–pathogen associations in agricul-

ture and other managed landscapes� (Jeger,

Chapter 1).

The first two chapters are referred to as

overviews. The first chapter is effectively an

overview of the book. The second has a focus

on plant virus transmission and epidemiology

and, amongst other aspects, provides an

overview of recently developed mathematical

models regarding aspects of vector, virus

transmission and epidemiology. Mathemat-

ical models are presented again in the final

two chapters. While the maths is beyond the

non-modelling specialist, it is clear from the

texts that the interaction between sophisti-

cated detection methodology and epidemio-

logical models is critical to the management

of disease.

Authors were asked to evaluate critically

the potential for biological control of or

by the system they are studying. For example,

the focus of Chapter 3 is on the maintenance

of vegetative incompatibility in fungal popu-

lations. However, the important implication

of this is that a high diversity of vegetative

incompatibility in fungal populations will

hamper biological control of pathogenic

fungi using mycoviruses that reduce fungal

virulence, because horizontal gene transfer of

such mycoviruses is hampered between in-

compatible fungal strains.

As the title of the text refers to plant–

pathogen associations one might not expect to

see included fungal endophytes (Chapter 4)

and bacterial endophytes (Chapter 6). How-

ever, one of the most accessible chapters is that

on fungal endophytes, where detailed research

data are summarized in tables and informed

comment provided in the text. Clearly, genet-

ical, physiological and ecological interactions

inform this plant–microbial association – the

most well-known effects being the negative

association between drought and the health of

the grazing stock and the positive protection

by the endophyte of the plant from insect

herbivores, and also nematodes. Direct refer-

ence is also made to the fact that different

chemical compounds lead to protection

against insect herbivory and to stock toxicoses

and how this information may be used to select

for the positive effects while avoiding the

negative effects of the association.

Both chapters 8 and 9 present information

concerning biocontrol of virulent pathogens

by utilizing avirulent isolates. Smith and

Saddler (Chapter 9) focus on bacterial wilt

and the potential of avirulent mutants of

Ralsonia solanacearum as biocontrol agents.

Hidden within this chapter is reference to the

fact that avirulent strains of Agrobacterium,

as well as a genetically modified strain, are

marketed as biocontrol agents for tumori-

genic Agrobacterium.

Alabouvette et al. (Chapter 8) suggest that

the use of Fusarium strains against patho-

genic Fusarium wilts will be based on being

able to characterize different strains. The

authors provide details of a strategy to

develop such a control agent. However, they

are critical of the lack of field data showing

efficacy under commercial conditions and

point out the fact that the abiotic conditions

necessary to establish populations of non-

pathogenic F. oxysporum over a sufficient

period of time to control the disease, still tend

to be ignored.

Chapter 10 provides a useful review of the

use of cross protection to protect against se-

vere virus strains, as well as referring to gene

silencing as a major component of the

mechanism of cross protection. Lecoq and

Raccah also highlight the real risks associated

with this form of biocontrol, and point to

examples of current use.

Tripartite interactions are referred to when

the herbivore–pathogen–plant interaction is

described (Chapter 11). Successful weed

control has occurred when initial wounding

by the insect herbivore opens sites for entry

of necrogenic plant pathogens. The biology

of these interactions is based on signalling

pathways. The mutually antagonistic effects

of salicylic acid and jasmonic acid are des-

cribed, but omitted from this chapter are the

equally interesting effects on the predators of

the herbivorous insect, of the volatiles re-

leased from challenged plants. However, this

facet is referred to by Kiss (Chapter 12) who

mentions the concept of volatile signals re-

leased from chewed plants guiding parasitoid

wasps to the caterpillars – providing evidence

of clear feedback signals between the first

and third trophic levels.

With emphasis on the fact that parasites

and hosts are components of multitrophic

interactions, several chapters cover the effects

on the plant host of reducing the fitness of the

primary parasite (e.g. Chapters 5, 7, 12, 13,

14 and 15) – several authors point out that

the organism that reduces the fitness of the

primary parasite, and which one might target

as a biocontrol agent, may also target other

more beneficial microbes. For example, chi-

tinase-mediated mycolytic activity (Chapter

� 2003 Blackwell Publishing Ltd, Journal of Biogeography, 30, 155–157

156 Book Reviews

7) might well be destined to remain within

the laboratory because of potential harmful

effects on mycorrhizal networks.

Overall this book contains a wealth of

information. It has been carefully edited such

that it is both readable and highly informat-

ive, with very few errors of grammar or

syntax. However, if one of the aims of the

book was to convey the message concerning

the need to study complexity, that message

may only reach scientists interested in this

area of research. The opportunity to convey

this message to a wider, less-specialist audi-

ence could have been taken in Chapter 1:

while an excellent overview of the book,

Chapter 1 could have been written in a more

general manner to attract the attention of the

non-specialist, integrating the biology with

the potential or otherwise for biological

control. It would be good to see the book

reach a wide audience, but it is more likely to

be read by specialists and graduate-level

students – indeed students focused on mo-

lecular plant–microbe interactions ought to

be referred to any one of the chapters in this

book to alert them to the �complexity of plant

disease in the field� (Jeger, Chapter 1).

P A U L A J A M E S O N

Institute of Molecular BioSciences,

Massey University,

New Zealand

E-mail: p.e.jameson@massey.ac.nz

� 2003 Blackwell Science Ltd, Journal of Biogeography, 30, 155–157

Book Reviews 157