烟粉虱在非露地越冬地区的田间扩散研究

Studies on diffusion of Bemisia tabaci Gennadius overwintering in the protecting fields

通过系统调查和定点观察，对在非露地越冬地区田间烟粉虱的扩散规律进行研究。结果表明：在江苏兴化市（烟粉虱的非露地越冬地区）烟粉虱可在双膜覆盖的大棚内越冬，6月上、中旬大棚揭膜后从温室向大田扩散，扩散时间持续35-45d，扩散距离1000-1500m，田间虫口密度随着距虫源距离的增大而降低，在500m以内的区域内虫量较大。田间种群动态与距虫源距离有关，500m处的虫口高峰比10m处迟13d左右。风向对烟粉虱的扩散方向有明显影响，而高大障碍物对烟粉虱的扩散有明显的阻滞作用。

Through systematic survey and spot inspection, the diffusion of Bemisia tabaci Gennadius overwintering in the protecting fields was studied. The results showed that B. tabaci in Xinghua could overwinter in the greenhouse covered with double-layer film. And they started to diffuse from the uncovered greenhouse to the open field during the first and second ten days in June. The diffusion lasted 35-45 d, and the diffusion distance ranged about 1 000 to 1 500 m away from the source. The population density was negatively correlated to the distance from the source. The majority of the insects were 500 m within the insect source. The population dynamic was closely related to the distances from the source. The peak of B. tabaci population at the place of 500 m away from the source occurred 13 d later than that at the place of 10 m. Wind produced significant effects on the diffuse direction, and large barriers made a significant retardation action on the diffusion of B. tabaci.