Behavioral Response Of Conogethes Punctiferalis(Guenée) To Three Kinds Of Fungus-infected Apples

The yellow peach moth,Conogethes punctiferalis(Guenée)(Lepidoptera: Crambidae)is an important borer pest.The volatiles released from host plants infected by microorganism affect the behavioral responses of insects such as finding and locating hosts,selecting oviposition sites and so on.In our prophase rese arch,the behavioral response of C.punctiferalis was tested towards volatiles of Penicillium-infected apples.Now,the effect of three kinds of fungus-infected apples on the behavioral response of C.punctiferalis was discussed in this paper,which would provide a theoretical basis for monitoring and controlling C.punctiferalis using the principle of chemical ecology.The results are present as follows:(1)To determine the relationship of behavioral response of C.punctiferalis and apple volatiles of four treatments,oviposition selection test and behavioral tendency test through four-arms olfactometer were carried out.The apples infected with Rhizopus oryzae(ROA),apples infected with Colletotrichum gloeosporioides(CGA),apples infected with Penicillium crustosum(PCA)and healthy apples(NIA)were experimental materials.The results showed that the attraction of four treatments' apple volatiles to C.punctiferalis ranked as ROA,CGA,PCA and NIA from the biggest to the least.The volatile released from microorganism-infected apples played an important role in the behavioral response of C.punctiferalis,preliminarily demonstrating the synergy relationship among insect,host plant and microorganism.(2)Dynamic headspace trapping,solvent eluting and GC-MS were used to capture and identify the volatiles of different kinds of fungus-infected apples.The results showed that the volatiles of three kinds of fungus-infeced apples were significantly different.A total of 35 compounds were detected from ROA volatiles,with(E,E)-a-farnesene and Hexanoic acid,2-methylbutyl ester as the main components.There were 35 kinds of compounds in GCA volatiles,with(E,E)-a-farnesene,2-methylethyl butyrate,hexyl 2-methylbutyrate,and ethyl caproate as the main components.There were 27 kinds of compounds in PCA volatiles,with(E,E)-a-farnesene as the main components.There were 33 kinds of compounds in NIA volatiles,with(E,E)-a-farnesene and butyl caproate as the main components.(3)The effect of 24 kinds of volatile components on the behavioral response of C.punctiferalis was determined by Y-tube olfactometer.The results showed that 2-methylbutyl-3-methyl butyrate,2-methyl-1-methyl ethyl butyrate,8-methyl-cyclotetrasiloxane and hexyl propionate had a certain attraction effect on mated female moths,but hexyl acetate and hexyl caproate had a certain repellent effect.Propyl caproate,amyl caproate,ethyl butyrate,ethyl octanate,dodecyl-cyclohexasiloxane and heptacosane had a certain attraction effect on unmated female moths,but hexyl butyrate had a certain repellent effect.2-Methylbutyl-3-methyl-butyl ester,octamethyl-cyclosiloxane,ethyl butyrate,ethyl octanate,and heptacosane had a certain attraction effect on male moths,but 2-methyl butyl acetate had a certain repellent effect.In summary,there were significant differences in volatiles of three kinds of fungus-infected apples and the behavioral responses of C.punctiferalis.Among ROA and CGA volatile components,C.punctiferalis had a strong attraction or repellency to the single compounds which would lay a foundation to explore green and harmless attractants and repellents of C.punctiferalis by combining with the "push-pull" strategy in the future.