| Myzus persicae(Aphididae: Hemiptera)is one of the most important agricultural pests in China.M.persicae has the characteristics of wide hosts range,strong reproductive capacity and small individuals are easy to hide.Therefore,it is difficult to carry out effective prevention and control of M.persicae.However,it is urgent to develop green and efficient sustainable prevention and control technologies for M.persicae under the concept of green plants protection.Insects rely on their sensitive olfactory system to recognize odor molecules in the environment to complete their intraspecific and interaspecific chemical information exchange.The development of insect behavior regulators based on host plants volatiles is one of the hot topics in green pest control.At present,the olfactory molecular mechanism of the M.persicae recognition of host plants volatiles is not clear.In this study,the M.persicae colonized in five host plants(Nicotiana tabacum,Spinacia oleracea,Capsicum frutescens,Brassica oleracea and Brassica pekinensis)were studied.Transcriptomics,analytical chemistry,molecular biology,electrophysiology and behavioral techniques were used to detect the odorant receptors colonized in these five host plants.The olfactory recognition mechanism of M.persicae in the recognition of host plants volatiles was preliminarily explored,The main results are as follows:(1)A total of 32 volatiles were identified from 5 host plants of M.persicae.In this paper,GC-MS was used to detect the volatiles of five kinds of host plants seriously damaged by M.persicae.The results showed that the volatiles of different host plants were different,The compositions and contents of volatiles produced by the five host plants of M.persicae showed similarities and differences.(2)A total of 49 odor receptor genes(MpORs)were identified from the antennae transcriptome data of M.persicae on 5 host plants,of which 25 were full-length.According to the FPKM values of MpORs,A total of 7 differentially expressed MpORs were screened.Among them,MpOR3 c,MpOR20 and MpOR40 were successfully cloned in this paper.The expression level of MpOR3 c is extremely low when the M.persicae colonizes B.pekinensi.The expression level of MpOR20 is extremely low when the M.persicae colonizes B.oleracea.The expression level of MpOR40 is extremely low when the M.persicae colonizes N.tabacum.(3)MpOR3c,MpOR20 and MpOR40 are the main receptors for nonanal,α-pinene and eucalyptol,respectively.In this paper,three successfully cloned differentially expressed MpORs were studied in vitro by using the Xenopus oocyte-bipolar voltage clamp system with 32 host plant volatiles as odor stimuli.The results showed that MpOR3 c could be activated by four aldehyde volatiles: nonanal(647.21 n A),decanal(622.24 n A),octanal(388.2 n A)and n-hexanal(357.07 n A),among which nonanal induced the largest electrophysiological response;Aldehyde volatiles that activate MpOR3 c were not detected in B.pekinensi,and the expression of MpOR3 c was extremely low in the antennae of the M.persicae colonized on B.pekinensi,indicating that MpOR3 c has the characteristics of adaptive expression when the M.persicae colonizes different host environments.(4)Nonanal was attractive to M.persicae colonized in N.tabacum.To further clarify the role of MpOR3 c in the recognition of nonanal in the perception of host plants by M.persicae.In this paper,the behavioral responses of M.persicae colonized in N.tabacum and B.oleracea were tested by petri dish method.The results showed that 1 μg/μL nonanal significantly attracted the M.persicae colonized on N.tabacum(P < 0.05),but had no significant behavioral effects on the M.persicae which colonized on B.oleracea(P > 0.05).In conclusion,the olfactory sense of the M.persicae colonized under different host conditions showed obvious plasticity in order to adapt to different hosts.provides a theoretical basis for further development of M.persicae behavior guidance control agent in the green provides important reference for prevention and control of pests. |
PDF Full Text Request