8 December 1995

Sting em with a wasp

WASPS offer cheap and effective control of low levels of seed weevil and pod midge in winter oilseed rape, recent MAFF and HGCA-funded work has shown.

One of the tiny parasitoids, Trichomalus perfectus, readily attacks seed weevils. Another species, Platygaster, can be attracted into crops with baited traps. It then multiplies and kills midges, explains ADASs David Alford.

"Routine use of insecticides is unnecessary. Crops rarely exceed the treatment threshold of two weevils a plant, so significant savings can be made by using natural control." &#42