Effects Of Intercropping Tea Plantation With Green Manure On The Green Leafhopper And Main Natural Enemies Of Pests

Intercropping in tea plantations is an effective measure that can impact pests and natural enemy communities. The experiment was conducted at the Zhiqing Farm ecological tea garden in Minhou, Yangli, Fuzhou, from May 2012 to November 2012. A vacuum machine was employed to investigate the population dynamics of the main natural enemies of tea pests and the green leafhopper, in addition to the changes in community structure of the natural enemies in tea plantations with three different types of intercropping(the green manure-cultivated white clover and Indian cowpea crops and the control tea plantation). The results showed that intercropping had no significant effect on the population dynamics of the green leafhopper. There was also no significant difference in the structure of the spider communities at three different plantations. However, intercropping with white clover and India cowpea had a significantly different impact on the number of parasitoid species and diversity index, which were much higher than the control tea plantation.Three different sampling methods (the sucking method, sticky plate method and knock-collect method) were applied to randomly collect individuals of the green leafhopper in the three different tea plantations according to position of the tea plants on the hillside from bottom to top. The results showed that the sucking method collected more green leafhoppers, showing significant differences compared with other two methods. The height factor had little effect on the number of green leafhopper individuals collected. The number of green leafhoppers collected in the white clover and India cowpea intercropping region were greater than in the control tea plantation.Tea shoots collected from three different types of tea plantations were dissected to study the density of green leafhopper eggs and the rate of egg parasitization. It was found that the density of green leafhopper eggs reached a peak in late June and early November of 2012, and the peak rate of wasp parasitism occurred in November. Intercropping with white clover and India cowpea had little effect on the density of green leafhopper eggs and rate of egg parasitism. The egg density found within the natural tea plantation ground cover was lower than in the intercropping areas, while the egg parasitism rate was higher.