Biological Control in Victorian Grape Vines using Trichogramma

Dr. David Bennett

Centre for Environmental Stress and Adaptation Research

La Trobe University

Order : HymenopteraFamily : Trichogrammatidae

Genus : Trichogramma

Microscopic wasps 145 species worldwide Natural enemies of moths Egg parasitoids

What is Trichogramma? A WASP

Trichogramma funiculatum

Order : HymenopteraFamily : Trichogrammatidae

Genus : Trichogramma

Microscopic wasps 145 species worldwide Natural enemies of moths Egg parasitoids

What is Trichogramma? A WASP

T. funiculatum and T. carverae

Order : HymenopteraFamily : Trichogrammatidae

Genus : Trichogramma

Microscopic wasps 145 species worldwide Natural enemies of moths Egg parasitoids

What is Trichogramma? A WASP

Trichogramma Life Cycle

What are egg parasitoids?

Different to regular parasites Trichogramma wasps lay their eggs into the

eggs of moths Instead of a caterpillar emerging, a fully

grown wasp climbs out Egg parasitoids are parasites that have a

free-living adult stage Similar to the bad guys in the movie Aliens!

T. brassicae on a Helicoverpa moth egg

Trichogramma in Biological Control

Currently the most widely used insect biological control agents in the world

Natural enemies of over 200 pest moth species whose caterpillars attack agricultural crops

Released on more than 8 million hectares

Pests in Australia

Examples of economically important pests include:– Helicoverpa (budworm) in processing

tomatoes– Epiphyas postvittana (Lightbrown Apple

Moth) in Chardonnay grapevines The latter damage grapes directly and spread

Botrytis (bunch rot) Control is difficult with chemical sprays

because this species is a leaf roller

Chardonnay grapevinesChardonnay grapevines

Lightbrown Apple Moth in grapesLightbrown Apple Moth in grapes

Pests in Australia

Examples of economically important pests include:– Helicoverpa (budworm) in processing

tomatoes– Epiphyas postvittana (Lightbrown Apple

Moth) in Chardonnay grapevines The latter damage grapes directly and spread

Botrytis (bunch rot) Control is difficult with chemical sprays

because this species is a leaf roller

Lightbrown Apple Moth

Epiphyas postvittanaEpiphyas postvittana

TrichogrammaTrichogramma in Australia in Australia

Several endemic species attack pest moth species

Natural Trichogramma parasitism rates are inadequate for control and too late in the season

Trichogramma carverae is a species which can be bred in captivity on a grain moth host

Breeding these wasps in huge numbers allows us to release them in grapevines where the pest has been found.

LBAM eggs

Trichogramma

Lightbrown Apple Moth cycle vs Lightbrown Apple Moth cycle vs TrichogrammaTrichogramma cycle cycle

TrichogrammaTrichogramma in Australia in Australia

Several endemic species attack pest moth species

Natural Trichogramma parasitism rates are inadequate for control and too late in the season

Trichogramma carverae is a species which can be bred in captivity on a grain moth host

Breeding these wasps in huge numbers allows us to release them in grapevines where the pest has been found

Wasp colony

Trichogramma carverae reared on eggs of the grain moth Sitotroga cerealella

Population founded from 18 wasps collected in Mildura

Colony maintained in a controlled environment room at 25C, in constant light, at 60% humidity and provided with honey and fresh eggs every eleven days

TrichogrammaTrichogramma in Australia in Australia

Several endemic species attack pest moth species

Natural Trichogramma parasitism rates are inadequate for control and too late in the season

Trichogramma carverae is a species which can be bred in captivity on a grain moth host

Breeding these wasps in huge numbers allows us to release them in grapevines where the pest has been found

LBAM eggs

Trichogramma

• release timing is important

Lightbrown apple moth cycle vs Lightbrown apple moth cycle vs TrichogrammaTrichogramma cycle cycle

ConclusionsConclusions

Releases early in the season increase parasitism and improve the level of biological control

Can this bio-control agent replace chemical controls in Victorian grapevines?

Can we produce Trichogramma strains that are more effective against these pests?

AcknowledgementsAcknowledgements

Horticultural Research Development Corporation

Grape and Wine Research Development Corporation

Australian Research Council

Project aims

Select for host location ability on potted grapevines under glasshouse conditions

Fitness components selected for :– Dispersal ability– Orientation mechanisms– Survival rates– Host plant location– Flight ability– Host acceptance– Oviposition success

Glasshouse selections

100 potted vines in full leaf Approximately 4,000 wasps released 120 LBAM egg cards exposed for 3 days Parasitised eggs collected to continue each

line Assumption that each egg raft stung by one

female, so that top 3% were selected 9 selections (3 populations x 3 selections)

Further studies

Monitoring egg presence for timing releases Release application rates Dispersal patterns and persistence Life history tradeoffs Impact of food Host deprivation Heritability of body size, wing shape Impact of fungicides

R1

R4+5

MA

Cu1

Cu2

1A

2A 3A

Trichogramma carverae forewing structure