Project funded by Defra and the HDC

Aphids infesting the foliage of lettuce and brassica crops are becoming increasingly difficult to control. This is because 1) the range of useful/potent insecticides has decreased through the withdrawal of effective products, 2) of the incidence of insecticide resistance in field populations of Myzus persicae (peach-potato aphid) and, to a lesser extent, Nasonovia ribisnigri (currant-lettuce aphid) and 3) aphids become inaccessible to insecticides as crops mature.

The purpose of this 3-year project was to develop an IPM strategy for aphid control on lettuce and brassica crops. It focused on N. ribisnigri, M. persicae and Brevicoryne brassicae (cabbage aphid). The objectives of the project were to:

1. Transfer knowledge gained during the project to the horticultural industry.
2. Measure the susceptibility of adults and nymphs of three aphid species (Myzus persicae, Brevicoryne brassicae, Nasonovia ribisnigri) to proprietary biopesticides based on insect pathogenic fungi.
3. Devise insecticidal control strategies for the pest aphids of lettuce and brassica foliage that will minimise the development of insecticide resistance.
4. Develop an empirical forecast for Brevicoryne brassicae.
5. Develop and validate an IPM strategy for the control of pest aphids of salad and brassica crops.

This is the project final report