Ian H Gibbs, Louis E. Chinnery and Jeffery E. Jones for the 7th Annual Technical Conference of the BSTA, 1989

The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) is certainly one of the world’s most important pest species. It mainly attacks brassicaceous crops especially cabbage, Brassica oleracea L. var. capitata L., and cauliflower, B. oleracea var. botrytis L.. It is found north of latitude 60° in Iceland, throughout the temperate zone and in the tropics (CIE, 1967). Hardy (1938 cited by Ooi, 1986) suggested that it probably originated in the Mediterranean region which was also the evolutionary centre for the B. oleracea crops

All Brassicas contain glucosinolates which, when the leaves are damaged, give rise to bitter tasting and goitrogenic substances: isothiocyanates, thiocyanates, nitriles and goitrin. Selection, from the start of domestication, must have been for plants which were less bitter-tasting (Thompson, 1976). Unfortunately, this improvement in taste was at the cost of reducing the plants natural defense against pests.

Insecticide resistance in Diamondback moth in Barbados pdf