Agroecology of a salad crop pest in New Zealand

Event Date: 
Wednesday, 30 August 2017 - 1:00pm
Scaptomyza flava. Credit: Dick Belgers

Speaker: Ryan Rayl, PhD Student at the Bio-Protection Research Centre

Venue: B4 Burns Building, Lincoln University.  

In this seminar, PhD student Ryan Rayl will describe his research project to enhance biological control of the leaf-mining fly in salad brassica crops.

A key pest of brassicas worldwide is the leaf-mining fly, Scaptomyza flava, the larvae of which can cause cosmetic damage leading to crop rejection by supermarkets/consumers. In climates where leafy salad brassicas are harvested all year, the flies are almost always present. This necessitates control throughout the entire harvesting season and usually consists of the prophylactic application of insecticides. One way of ameliorating the negative environmental impacts of this approach is to enhance the effectiveness of biological control by providing alternative food sources for natural enemies. Planting of selected flowering plants can be useful in this respect, as many parasitoids and other insects feed on certain nectars. This, in turn, can improve their efficacy by increasing fecundity and longevity of natural enemies. This PhD aimed to find selective flowering plants that provided more benefit to the natural enemies when compared with the pest. This work was conducted through a series of laboratory and field experiments.