Abstract:The diamondback moth (DBM), Plutella xylostella (L.), is an important, damaging insect of cruciferous crops worldwide and has become the most serious insect pest on crucifers in South China where the frequency of outbreaks has increased rapidly since the 1970s. The diamondback moth feeds only on cruciferous crops and its host preference is related to concentrations of mustard oils and glucosides in crucifers. Although all members of the family Cruciferae can serve as host plants certain species of crucifers...