Effects of aphid-resistant varieties of peach on the growth dynamics of insect populations in the field

【Objective】The purpose of this study was to find out the changes of insect community structure in the field growing aphid-resistant varieties of peach tree by using the method of insect mathematical ecology, so as to explore the effects of the aphid-resistant varieties on the species and numbers of insects caused by non-target insects. It would provide a reference for the plant protection cultivation measures adopted when the aphid-resistant varieties come into use in the future.【Methods】The aphid-resistant varieties and control varieties were used in the experiment in the Xinxiang Comprehensive Experimental Base of Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences , In the case of using the aphid-resistant variety, aphid control was not applied in the early spring. The dynamic changes of insect community composition and number of insect community individuals in the plots using the aphid-resistant variety and control variety were analyzed by Malay net collection method, insect sex pheromone trapping method and visual survey method.【Results】A total of 5955 insects samples were collected in the plot using aphid-resistant variety and they belonged to 9 orders. They were Diptera, Hemiptera, Lepidoptera, Hymenoptera, Arachnoidea, Neuroptera, Coleoptera, Orthoptera, andThysanoptera. A total of 4606 insect samples were collected in the CK plot and they belonged to 8 orders. They were Diptera, Hemiptera, Lepidoptera, Hymenoptera, Arachnoidea, Neuroptera, Coleoptera and Orthoptera. The total number of insects collected in the plot using aphid-resistant variety was greater than those in the CK plot, and there was no significant difference in the percentage of insects of each order in the two plots. The pests in the plot using the aphid- resistant variety accounted for 40.70% of the total number of the insects and 35.93% in the control plot. The pests included Lepidoptera, Hemiptera and Arachnoidea. The beneficial insects in the plot using the aphid-resistant variety accounted for 15.95% of the total number of the insects and 12.26% in the control plot. The beneficial insects included Syrphidae, Coccinellidae and lacewing. The other insects were neutral insects, mainly including Diptera, Coleoptera, Orthoptera and Thysanoptera, they accounted for 43.36% of the total number of the insects in the plot using the aphid-resistant, and 51.81% in the CK plot. The benefit/pest ratio of the plot using the aphid-resistant variety and and of the control plot were not significantly different in terms of the overall trend. The total number of insects collected in the the plot using the aphid-resistant variety was greater than those in the CK plot, and the total number of insects in the early stage of the plot using the aphid-resistant (late March to early June) was greater than those in the control plot, and the number was basically the same in the later stage. The trend of the total number of insects in the plot using the aphid-resistant variety and in the control plot was basically consistent with time. Compared with the CK plot, the total number of insects in the dominant insect populations (Diptera, Hemiptera, Lepidoptera and Hymenoptera) in the plot using the aphid- resistant variety had a tendency to peak earlier and increase the total number during the pest occurrence season. The number of most neutral insects and natural enemy insects in the plot using the aphid-resistant variety also tended to peak earlier and increase total number.【Conclusion】Using the aphid-resistant variety in the orchard could possibly increase the total number of insect individuals due to the lack of the use of the pesticide to peach aphids in the early spring