Olfactory Responses Of Sitobion Avenae And Its Parastic Wasps Based On SSR And EAG Techniques

Triticum aestivum L.is one of the most grain crops in China.Wheat aphids are detriment to wheat production not only by squeezing wheat phloem sap,but spreading virus and secreting honeydew causing soot disease to wheat plant,bring about reducing the photosynthetic efficiency of wheat plants,thus seriously affecting wheat yield and quality,resulting in a year-on-year reduction in wheat production of more than 10%,and more than30%in case of outbreak.The long-term use of chemical pesticides has brought about a series of critical problems such as pesticide residues,environmental pollution and pest resurgence.Therefore,it is of great significance to develop new technologies to control wheat aphids,reduce the use of chemical pesticides,and to ensure national food security,agricultural product safety and ecological safety.In this paper,the single sensillum recording?SSR?and the electroantennography?EAG?measurement technique were combined with the olfactory behavior test to assess the electrophysiological and olfactory behavioral responses and reaction threshold of wheat aphids as well as two species of parasitic wasps to the plant volatiles which are 6-methyl-5-Hepten-2-one and cis-3-hexenol and to aphid pheromones which are aphid alarm pheromone?E?F?and sex pheroneme?NEP?.In order to enrich the theory of ecological regulation and behavioral regulation of aphids,the research provides a theoretical foundation for aphid management based on signal compound by new technology.The results are as follows:The SSR measurement of the primary sensillum on the sixth segment of aphid antennae showed that the reaction peaks of winged aphids to E?F were the highest and the number of that were the most among the four volatiles,compared to wingless aphids.In plant volatiles,the maximum response of both winged and wingless aphids to 6-methyl-5-hepten-2-one is greater than that of p-cis-3-hexenol,and 6-methyl-5-heptene 2-ketone can induce stimulation peaks at lower concentration?100-times diluted?;when it comes to aphid pheromone,the maximum reaction intensity of both winged and wingless aphids to E?F is greater than that of NEP;additionally,the response of winged aphids is stronger than that of wingless aphids.The EAG assess of Sitobion avenae to the volatiles showed that the responding tendency of winged and wingless aphids tend to be consistent.The EAG response to6-methyl-5-hepten-2-one and E?F were stronger than that to cis-3-hexenol and NEP,respectively.The strongest E?F reaction was detected when it was 0.01?g·?L^-1 either of winged or wingless aphids.For 6-methyl-5-hepten-2-one,female Aphidius gifuensi had a high response at low concentration while male Aphidius gifuensiand and Aphidius avenae had a high response to higher concentrations.The reaction to cis-3-hexenol reached the highest level at a concentration of 100-times dilution.For E?F,the response of male Aphidius gifuensi was strong at high concentrations while the other three types responded strongly to lower concentrations.The responding level of Aphidius avena to NEP was lower than that of Aphidius gifuensi.Generally,the two species of parasitic wasps were more reactive to6-methyl-5-hepten-2-one than cis-3-hexenol and the reaction to E?F was stronger than to other volatiles.Four-arm olfactometer behavioral assess showed that 6-methyl-5-hepten-2-one had a significant repellent effect on winged or wingless aphids,while cis-3-hexenol had attractive effect on them.E?F showed obvious repellent effect while NEP did not express significant behavioral effects.Y-tube test showed that male Aphidius avenae was not significantly selective for various volatiles,but both male and female had a tendency toward two concentrations of E?F and6-methyl-5-hepten-2-one.In addition to cis-3-hexenol,the female Aphidius gifuensihas significant tendencies to aphid pheromones and plant volatiles.The tendency of male Aphidius gifuensi to E?f was significantly stronger than that of Aphidius avena.The female Aphidius gifuensi has a stronger response to sex pheromone than female Aphidius avenae.