Contents:

• Biological control• SNAP - Habitat manipulation• Lacewing, aphid and parasitoid• Tradescantia• Leaf miner• Possum

What is biological control?

Crop

Pest

Natural enemies

Crop

Pest

Natural enemies

Conservation biological control

Live longer

Habitat manipulation:

Floral resourcesShelter

Nectar

Alternative prey

Pollen

Predators like the lacewing have been responsible for decreases in economic damage to crops by reducing herbivorous pest species. Brown lacewing

Micromus sp.

The brown lacewing is both a predator of many small insects and it also feeds on nectar and pollen, making it omnivorous.

Pea aphid Acyrthosiphon pisum)

The floral resource buckwheat Fagopyrum esculentum, which has a sucrose-rich nectar.

Other ways for aphids to die.....

Parasitoid wasp laying eggs in aphid

The parasitoid larva eats the mummified aphid from the inside

out!

The adult parasitoid then emerges from the aphid corpse!

Biological Control of Tradescantia

Tradescantia fluminensis

• Introduced to New Zealand 1910 from South America

• Established in many native forests in the North Island• Forms a dense matt on the forest floor• Suppresses growth and regeneration of native plants• Can regenerate from a single 1cm node• Also known as wandering jew

Tradescantia Leaf Beetle

• Neolema ogloblini-introduced November 2010• Released at 5 sites between Auckland &

Northland

Neolema abbreviata Lema basicostata

Imported Beetles Not Yet Released

Beetle Biological Control Agents

Neolema ogloblini

Adult and larvae feed on leaves

Neolema abbreviata

Larvae feed on growing tips of

plant

Lema basicostata

Adult and larvae feed on stems

Tip

Leaves

Stem

Current Lincoln University Research

Determine effectiveness of three beetles to control Tradescantia fluminensis :

Decide if three beetles are most effective, or possibly just one beetle could be effective enough to reduce Tradescantia growth and spread

The holm oak hedge, Quercus ilex

Leaves 30 cms into the hedge show evidence of leaf mines. Fresh new outer growth not yet showing signs of mines

The Holm Oak, Quercus ilex

Acorn and leaves from the evergreen oak hedge

Leaf mines

The holm oak twig with 5 leaves showing presence of mines. One leaf not infected

Leaf miner, Phyllonorycter messaniella

The adult moth on the leaf surface

Leaf miner

The larva or caterpillar of the leaf miner and a tidy pile of frass

Leaf miner attacked by the parasitoidfrom Te Taiao. No 4. Nov 2004, ISSN 1176-2454 Tangled Web: A new addition to the natural enemy suite controlling leaf-miner.

Possum biocontrol –funding for this researchat Landcare Researchhas been cut.

The possums own biological systems used to interfere with the process by which sperm fertilises the egg.

This response will be triggered by proteins that make up part of the coat of the sperm or egg, and will stop female possums producing eggs and/or interfere with the fertilisation of any eggs produced.

That way, no or very few baby possums will be born, so possum numbers will decline as the adults die off and there are no young to replace them.

The biological control agent based on the sperm or egg proteins will be made into baits and fed to possums from bait stations.

LEARNZ

www.learnz.org.nz/field-trip-chooser.php2011 examples include invasive species and

their control.Marine reservesHigh Country wetland ecologyNorthern wetlandsFreshwater ecologyBirds of prey

ADDITIONAL INFO:• Colour pictures: Aphid, lacewing, parasitoid

wasp• Worksheet for everyone: Ecology – pea aphid,

lacewing and parasitoid wasp• Web site: www.lincoln.ac.nz/scienceoutreachHas worksheets on:biological control of gorse, gorse spider mite,

gorse pod moth, investigating aphids, leaf miner

PS.......Have a look at work done by:

Professor Steve Wratten, Lincoln University onthe "Greening Waipara" programme, which is using native vegetation in vineyards to enhanceecosystem services:http://bioprotection.org.nz/greening-waipara

Acknowledgements

• Tradescantia information and resources – current M.Sc student, Sam Reed

• Video clips, slides and resources on insect bio-control courtesy of Professor Steve Wratten, Eric Wyss and Dr Sophia Orre

• All the contents of this presentation draw from work carried out by researchers at Lincoln University