3种虫生真菌对烟蚜茧蜂寄生力及其子代的影响OA

[Objective]This study investigated how infection of Myzus persicae with three entomopathogenic fungi affects the parasitic behavior and progeny fitness of Aphidius gifuensis.[Method]Myzus persicae was treated by using the immersion method with spore suspensions of three fungal species at three distinct concentrations:1.00×106,1.00×107,and 1.00×108 spores/mL.Subsequently,the parasitism rate of Aphidius gifuensis on fungus-infected aphids was determined via the laboratory leaf culture method.The emergence rate,female ratio,adult lifespan,and hind tibia length of the F₁ progeny were also observed and measured.[Result]Infection by the three fungal species significantly reduced the parasitism rate of A.gifuensis(P<0.05).At the concentration of 1.00×108 spores/mL,the parasitism rate in the Aspergillus oryzae treatment group was the lowest(14.00%),which was approximately 48.8%lower than that in the control group(27.33%).Aspergillus flavus treatment significantly inhibited the emergence rate of progeny;at the highest concentration,the emergence rate was only 62.10%,a decrease of 18.9%compared with that of the control(P<0.05).Aspergillus oryzae treatment significantly shortened the adult lifespan of F₁ progeny(decreased by 3.55 h compared with that of the control,P<0.05),while Fusarium fujikuroi treatment significantly reduced the hind tibia length of F₁ adult wasps(decreased by 16.20 μm,P<0.05).None of the three fungal treatments had a significant effect on the female ratio of the progeny(P>0.05).[Conclusion]This study confirmed that infection of Myzus persicae by entomopathogenic fungi significantly reduced the parasitic success rate of Aphidius gifuensis.In addition,the effects of different fungi on the offspring fitness of the parasitoid were species-specific:Aspergillus flavus mainly affected the emergence rate,Aspergillus oryzae affected adult lifespan,and Fusarium fujikuroi affected morphological development.These results indicated that when formulating an integrated biological control program for Myzus persicae,the potential negative impacts of the selected entomopathogenic fungi on the parasitoid natural enemies should be carefully evaluated.