Spatial summer–autumn distribution of the diamondback moth, Plutella xylostella (L.) and its parasitoids in cauliflower fields

Abstract

AbstractAgricultural intensification and greater production of Brassica vegetable and oilseed crops over the past two decades have increased the pest status of the diamondback moth (DBM), Plutella xylostella L., and it is now estimated to cost the world economy US$4–5 billion annually. Our understanding of some fundamental aspects of DBM biology and ecology, particularly host plant relationships, tritrophic interactions, and migration, has improved considerably but knowledge of other aspects, e.g. their spatial distribution and relative abundance, remains surprisingly limited. In this study, the summer–autumn spatial distribution of the diamondback moth, P. xylostella, and its parasitoids, including Diadegma anurum, Cotesia plutellae and Oomyzus sokolowskii in cauliflower fields south of Tehran were assessed from late May until October 2011. Each plant was presumed as a sampling unit and sampling was carried out every two weeks. The spatial distribution pattern of all life stages of diamondback moth and i...