Presentation on theme: "Contents: Biological control SNAP - Habitat manipulation Lacewing, aphid and parasitoid Tradescantia Leaf miner Possum."— Presentation transcript:
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 resources Shelter 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 abbreviataLema 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 parasitoid from Te Taiao. No 4. Nov 2004, ISSN Tangled Web: A new addition to the natural enemy suite controlling leaf-miner.
Possum biocontrol – funding for this research at Landcare Research has 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 examples include invasive species and their control. Marine reserves High Country wetland ecology Northern wetlands Freshwater ecology Birds of prey
ADDITIONAL INFO: Colour pictures: Aphid, lacewing, parasitoid wasp Worksheet for everyone: Ecology – pea aphid, lacewing and parasitoid wasp Web site: Has 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 on the "Greening Waipara" programme, which is using native vegetation in vineyards to enhance ecosystem services:
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