小菜蛾产卵对寄主的选择性及其应用初步研究

PRELIMINARY STUDIES ON OVIPOSITION PREFERENCE TO HOST PLANTS OF DIAMONDBACK MOTH, Plutella xylostella AND ITS APPLICATION

以广州、深圳种植的几种主要十字花科蔬菜，研究了小菜蛾对寄主的选择性．室内试验和田间调查结果基本一致：小菜蛾对芥菜、菜心的嗜好性最大，对萝卜、白菜次之，对芥蓝、花椰菜最差．根据小菜蛾喜爱在芥菜上产卵这一特性，进行了芥菜与芥蓝套种诱集防治小菜蛾的田间试验．结果表明，所有套种田中芥蓝上的小菜蛾卵数量都显著低于单种田（Ｐ＜０．０５），在芥蓝生长后期，单种田芥蓝中卵数量高出套种田近１０倍，芥菜中卵和幼虫数量是芥蓝中的好几十倍．说明用芥菜这类对小菜蛾产卵引诱性较强的作物与甘蓝类蔬菜套种可以用来诱集防治小菜蛾对后者的为害．

In order to investigate the agricultral control methods of the diamondback moth(DBM), Plutella xylostella (L.), oviposition preference of DBM to its host plants was studied. Among the six species of cruciferous vegetables,the female adult of DBM prefered to lay their eggs on the mustard( Brassica juncea Coss.) and flowering Chinese cabbage( B. parachinensis Bailey), and the number of eggs laid on radish( Raphanus sativus L.) and Chinese cabbage( B. campestris L.) was less, while the number of eggs laid on Chinese kale( B. alboglabra Bailey) and cauliflower( B. aleracea L . var. botrytis DC) was the least. Based on DBM preference to mustard, a trial measure that B. juncea was used as a trap crop for management of DBM, was carried out in Shenzhen, Guangdong Province. Preliminary studies indicated that Chinese kale( B. alboglabra ) cultivated at an interval of 5～10 meters followed by paired mustard rows could decrease the DBM population and reduce the application of insecticides.