The effect of different host arrange on the reproduction of Plutella Xylostella (L.)

• 1、Key Laboratory of Insect Ecology in Fujian, Key Laboratory of Integrated Pest Management on Crops in Fujian-Taiwan, Ministry of Agriculture, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002

Abstract：[Objectives] This study was aim to reveal the interference and trap effect on pests in multihost cropping system and explore its operated mechanisms. [Methods] This experiment was conducted under laboratory conditions, there were 5 different treatments, B. campestris/ B. oleracea, B. campestris/ B. juncea, B. campestris, B. juncea, B. oleracea respectively. The total number of eggs laid on each treatment for 5 d was compared to determine the effect of host arrange on reproduction. [Results] The total number of eggs which was laid on B. campestris/ B. juncea treatment was less than other treatments except B. oleracea treatment, however, the number of eggs respectively laid on B. campestris and B. juncea wasn't significantly different in this treatment, it was interference effect. By contrast, there wasn't marked difference between B. campestris/ B. oleracea treatment and B. campestris treatment or B. juncea treatment, and eggs laid on B. campestri was significantly more than on B. oleracea in mixed cropping treatment, it was trap effect. [Conclusion] There are different effect on P. xylostella with different host arrangements. This paper shows that not only trap crop but also mixed cropping two similar hosts can be used to control P. xylostella in fields. As it becomes difficult for P. xylostella to make decision when facing the similar hosts ,which disturbs its behavior on host selection that keeps pest populations at a low level.

Keywords： Agricultural entomology and pest control Dimondback moth, different host arrange, trap effect, interference effect, production