Diamondback moth–host plant interactions: Implications for pest management

The diamondback moth (DBM), Plutella xylostella (L.), is a destructive insect pest of cruciferous crops with a cosmopolitan distribution. Its genetic elasticity has enabled it to develop resistance to almost every insecticide applied in the field. Its natural host range is limited to cultivated and wild Brassicaceae that are characterized by having glucosinolates, sulfur-containing secondary plant compounds. Adults utilize an integrated suite of chemical and morphological cues for host plant location and recognition. Certain glucosinolates, cardenolides, plant volatiles, waxes, as well as host plant nutritional quality, leaf morphology and leaf color, or a combination of these factors, may trigger reproductive and feeding activities of DBM. Host plant resistance forms an important component of integrated pest management programs. In this review, we synthesize information on certain plant biochemical and morphological characteristics that have been investigated to promote DBM resistance to its host plants. The efficacies of transgenic crucifers and the potential role of trap cropping for the management of DBM are also discussed.