Herb growers use some of these successfully. Aphidius colemani gives good control of the peach-potato aphid, Myzus persicae. However, experience has indicated that none of these species control two "problem" aphids - hawthorn-parsley aphid Dysaphis apiifolia and mint aphid Ovatus crataegarius, in parsley and mint respectively.
A new aphid parasitoid mix, produced by Viridaxis and supplied by BCP Certis, contains three new parasitoid species in addition to those previously available - Aphidius matricariae, Praon volucre and Ephedrus cerasicola. Jude Bennison and ADAS colleagues are investigating whether the mix can be used to control the hawthorn-parsley aphid and the mint aphid.
ADAS findings so far are that several species in the commercial mix will parasitise both aphid species. Small-scale glasshouse experiments showed that A. colemani could give effective control of hawthorn-parsley aphid and that A. matricariae has potential for control of mint aphid. Current work is comparing the control given by individual parasitoid species and by the commercial species mix.
HDC project PE 006(a) aims to develop a preventive release programme for either single or mixed parasitoid species for effective control of both aphid species.
Horticultural Development Company
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