青花菜上桃蚜迁移及其天敌动态研究

目的]研究青花菜上桃蚜种群数量及其天敌动态。方法]选择有代表性的地块,调查青花菜和其他寄主上有翅桃蚜、无翅桃蚜和天敌数量并加以分析。结果]桃蚜可以在小白菜、菊花、萝卜和青花菜等作物上互相转移为害。在11月中旬以前桃蚜保持较低密度,11月中旬以后随着温度的降低,其数量显著增多,至12月上旬其数量达到高峰;天敌共有6科11种,其中六斑月瓢虫、菜小脉茧蜂为优势种;随着桃蚜种群的增加,天敌数量逐渐增加,具有明显的跟随效应;将桃蚜数量与天敌数量进行回归分析,桃蚜数量与天敌数量显著正相关。结论]佛山青花菜种植区桃蚜发生高峰期为11月至12月间。

Research on the Migration of Green Peach Aphids in Broccoli and the Dynamics of and Its Natural Enemy

Objective] The number of green peach aphid populations in broccoli and the dynamics of their natural enemy were researched.Method] The representative plot was chosen as experimental areas to investigate broccoli growth and the species of green peach aphids and natural enemies and the result was analyzed.Results] The green peach aphids might move from Chinese cabbage,chrysanthemum,radish,broccoli to other crops each other and the harm could be caused.Before the mid-November,the green peach aphid maintained lower density;after the midNovember,as the temperature reduced,their number was significantly increased and to early of December,the number of them reached the peak.There were 11 species in 6 families of natural enemy,among which,ladybug and braconidae were the dominant species.With the increment of the green peach aphid population,the number of natural enemy increased,which relation was obvious.The regression analysis of the number of green peach aphid and natural enemy showed there was significant positive relationship between of them.Conclusion] The peak of green peach aphid-occurring was in November to December.