Biology, Ecology, and Management of the Diamondback Moth in China.

The diamondback moth (DBM), Plutella xylostella (L.), costs the Chinese economy US$0.77 billion annually, and considerable research has focused on its biology, ecology, and management. Much of this research has been published locally and is inaccessible outside China. Since 1990 Brassica vegetable production has increased 20-fold and production practices have intensified, but losses continue to increase. Insecticide use is widespread and many DBM populations, particularly in southern provinces, are resistant to multiple compounds. The molecular bases of several insecticide resistance mechanisms are well understood, and genetic studies suggest that insecticide-resistant populations migrate northward in spring and that back migrations may occur in southern provinces. Fundamental studies have improved our understanding of the effects of temperature on DBM population dynamics and distributions and of interactions between DBM and its well-established parasitoid fauna. Nationally coordinated research is developing regional management strategies that integrate locally appropriate biological, physical, cultural, and insecticidal control, but sustaining their adoption will prove an enormous challenge.