粉虱座壳孢菌毒素杀虫活性试验

从福建省柑桔园内分离出的粉虱座壳孢菌(Aschersonia aleyrodis),经发酵培养,萃取得到内、外毒素的粗提物,并将其应用于防治烟粉虱和桃蚜的研究。实验结果表明,2龄粉虱和蚜虫对外毒素敏感,处理2d后的粉虱死亡率在80%以上,处理后的蚜虫死亡率随处理时间的延长和浓度的提高而增大。内毒素对粉虱也具有杀虫活性,而对蚜虫未检测到活性。座壳孢菌外毒素对蚜虫具有杀虫活性未见报道,是新的毒素资源。

Insecticidal Activity of Aschersonia aleyrodis Toxins

Crude extracts of Aschersonia aleyrodis endotoxins and exotoxins were obtained from submerged culture with organic solution and then used in an insecticidal assay against Bemisia tabaci and Myzus persicae.Investigation of insecticidal characteristic of the fungal toxins revealed that second instar nymphs of whiteflies and aphids were most susceptible to exotoxins and the mortality rate of second instar Bemisia tabaci nymphs could reach over 80% after 2 days treatment.Moreover,mortality rate of Myzus persicae increased with prolongation of treatment duration or increase in concentration of toxins.It showed that whitefly mortality was differently affected by endotoxins,but no biological activity against Myzus persicae.For peach aphids,exotoxins are the active secondary metabolites firstly reported from Aschersonia,which represents a new source of toxins.