Species Diversity of Natural Enemy Insects and Population Dynamic of Main Pest Insects in Changsha Tobacco Areas

Species diversity of natural enemy insects and population dynamic of main pest insects in Changsha tobacco areas were studied through wulti-site investigation and focused monitoring from 2014 to 2015. The results showed that 18 species of natural enemy insects were observed, including 5 dominant species, including Harmonia axyridis, Propylaea japonica, Coccinella septempunctata, Paederus fuscipes and Campoletis chlorideae. The numbers of species and individuals of natural enemy insects were small, and the control capacity against main pest insects was weak. Species diversity of natural enemy insects was the highest in June. The relationship between Myzus persicae and its natural enemy insects exhibited a hysteresis phenomenon, while the relationship between Lepidoptera pests and natural enemy insects exhibited a following phenomenon.