Viticultural research at Lincoln University is working to improve ecosystem services such as biological control of pests and disease using ‘ecological engineering’. Research in pest biocontrol is investigating the use of appropriate native and non-native flowering plants to provide ‘resource subsidies’ in the form of pollen, nectar, shelter and alternative prey. For example, buckwheat (Fagopyrum Esculentum) can be planted for the control of leafroller pests. Buckwheat nectar increases the longevity and fecundity of parasitoid wasps, the key biological control agent for leafrollers. As a result, leafroller populations can be bought below the New Zealand and Australian economic thresholds. Analysis of buckwheat nectar by HPLC has identified particular sugar ratios as being of key importance to its biocontrol properties. Current work is using these methods to analyse the sugar ratios in endemic New Zealand plants to predict their effectiveness as pest control agents.
Additional research is investigating the control of botryitis infection using organic mulches comprising aerobically and anaerobically composted marc, waste paper, grass clippings and mulched buckwheat plants. Normally, botrytis overwinters on vine prunings found on the soil surface, but these mulches accelerate the breakdown of these prunings, thus mitigating the amount of botrytis present.
Lincoln’s Centre for Viticulture and Oenology is involved in the ‘Greening Waipara’ programme, which aims to incorporate such ecological engineering practices into vineyards across the Waipara winegrowing region.
For further information about research on vineyard ecology, please contact Steve Wratten.