Predatory function system of the dominant predators for diamondback moth,Plutella zylostella
The species of predators for diamondback moth(DBM),Plutella xylostella(L.),and the predatory equivalency systems and functional responses of predators are provided in this paper. There are 50 species of predators for DBM in vegetable fields in the Yangzhou district. They belong to 2 classes,7 orders and 20 families of Arthropoda. The main predators of DBM include spiders,ladybirds,carabid beetles and earwigs. The predatory amounts of the main predators were determined. The predatory equivalency coefficients of the different predators in different developmental stages were calculated based on the potential predatory amount of each species. Thus,a predatory equivalency system was established and a threshold of multiple-species predators for DBM was proposed.At the rosulate stage of cabbage,if the ratio of predatory equivalency to pest equivalency surpasses 1：8.8,there is no need for supplemental control for DBM. If the ratio ranges from 1：8.8 to 1：17.7,there is still no need for supplemental control,but additional monitoring is required. If the ratio is less than 1：17.7,immediate supplemental control is needed. The functional responses of the predators to DBM could be described by the Holling(Ⅱ)equation.
Shu-De Zhu Hai-Tao Liu Lei Xu Yan Shi Jian Xu
Department of Plant Protection,University of Yangzhou,Yangzhou City,Jiangsu,China,225009
国际会议
北京
英文
161-165
2006-10-24（万方平台首次上网日期，不代表论文的发表时间）