Study on the Control Effect and Community of Natural Enemies of Dendrolimus punctatus in Different Type of Masson Pine Stand

Abstract This research was conducted in three different types of occurrence regions (frequent outbreak region (Ⅰ), accidental outbreak region (Ⅰ), safety region (Ⅲ)) of Dendrolimus punctatus in the Anqin City of Anhui Province. Nearly 50 species of natural enemies were found during the period of over tworyear experiment. Anastatus sp., Rogas dendrolimi and Exorista sp. are the major parasites at the egg stage, larva stage, pupa stage respectively and the highest parasitism rates of each species is 13.6%, 5.5%, 23.4% respectively.There are about 31 species of natural enemies in (Ⅰ), 37 species in (Ⅱ) and 42 species in (Ⅲ). The result shows that the index of diversity and evenness of natural enemies community in (Ⅲ) is higher than that of the other two regions. Study on similarity of natural enemies community shows that similarity coefficient is the highest one between (Ⅲ) and (Ⅱ) and that between (Ⅰ) and (Ⅱ) is the second.