Recognition And Responding Of Acyrthosiphon Pisum To Odor And Tracks Of Harmonia Axyridis

In the tritrophic interaction of host plants- phytophagous insects- natural enemies,phytophagous insects could recognize traces of its natural enemies through chemical compounds, then avoid to feed on the plants with traces of natural enemies. If phytophagous insects feed on the plants with predator traces, their development would be affected. We used a system consisted of Vicia faba Linn- Acyrthosiphon pisum(Harris)- Harmonia axyridis to investigate the influence of traces of H. axyridis on A. pisum in the laboratory, and the main results were showed as following:1、 The results of Y tube experiments showed that winged aphids preferred to the leaves without predator traces, but wingless aphids had no significant preference. Both winged and wingless aphids had no preference for the leaves with hexane extracts of H. axyridis traces.2、 The weight of adult aphids feeding on the leaves with predator traces reduced within 48 h,and their fecundity significantly reduced within 24-48 h. The weight of first instar nymph aphids showed no difference between feeding on the leaves without predators trace and on the leaves with predators trace. The weight of adult aphids feeding on the leaves with hexane extracts of predator traces reduced within the 0-24 h, and their fecundity significantly reduced within 24-48 h.3、 The results of EPG determination showed that np wave and the first probe time of feeding wave were extended.4、 GC-MS analysis results showed that H. axyridis traces contained alkanes, esters and alcohols. SPME results showed that there were a small amount of aphid alarm pheromone farnesene and caryophyllene ingredients in H. axyridis traces.In conclusion, A. pisum could avoid the leaves with H. axyridis traces, which contained alkanes, esters and alcohols. Winged aphids were more sensitive to predator traces than wingless aphid. When the aphids fed on the leaves with predator traces, their development would be affected.