Study on Temporal-spatial Dynamics of Empoasca flaoescens in Maize-potato Intercropping

Empoasca flaoescens (Fab.), which belongs to Cicadellidae Homoptera, is one of important potato pests. In order to study the effect of maize-potato intercropping on the temporal dynamics and spatial patterns of E.flaoescens,we set sweep trap every potato growing season from 2012 to 2013 in Daheqiao farm locating in Xundian, Yunnan Province. In this study, ANOVA was used to compare the differences of E.flaoescens abundance and dynamic between two years and two cropping systems,respectively. Five space distribution indexes, Taylor's exponential function and Blackith's index were used to analyze the spatial patterns of E.flaoescens. The results showed:(1) There were two population peaks every year in populations dynamics of E.flaoescens. While, there's no significant difference in populations dynamics between two sampling years, but the abundances in potato fields were significant higher than in maize-potato intercropping fields. (2) According to the comprehensive analysis of five space distribution indexes, the spatial patterns of E.flaoescens both in potato monocropping and intercropping fields are aggregation type, however, the aggregation times in monocropping fields were more than in intercropping fields.(3) According to the analysis of Taylor's exponential function and Blackith's index,the aggregation time and degree of E. flaoescens both in monocropping and intercropping fields were related to pest population density. Moreover, the reasons for the aggregation distribution of E.flaoescens also depended on the population density. Above all, the intercropping method of maize and potato can reduce the population density of E.flaoescens, and effect the aggregation degree and spatial distribution of the pest insect in farming fields.