Structure Differences of the Natural Insect Enemy Complex between Jujube Orchards Intercropped with Pasture and No Pasture

The communities and diversity of the beneficial insects on jujube trees were studied in jujube sites intercropped with pasture in Taigu, Shanxi province of China. The results showed that 8 orders, 25 families, 64 species and 5112.33plusmn30.65 individuals of insect natural enemies were found in the jujube sites intercropped with pasture site, while the corresponding numbers were 8, 35, and 3126.33plusmn23.36 in the jujube sites without pasture. The intercropped pasture site had significantly (P < 0.05) more beneficial insects than the non-intercropped site. The dominant species were Inocellia sp., Coccinella septempunctata, Chrysopa shansiensis, and Anysis saissetiae. The diversity and the evenness of the beneficial insect community in the intercropped site were significantly higher (P < 0.05) than those in the non-pasture sites. There were significantly smaller (P < 0.05) infestation rates of the fruit borers and significantly higher (P < 0.05) parasitism rates of the fruit borers in jujube orchards intercropped with pastures than that of no pastures in jujube orchards. Significantly greater (P < 0.05) net income was recorded from the treatments with pastures than the no pastures in jujube orchards. The results suggested that the structures and functions of beneficial insects were improved in the jujube sites intercropped with pasture than in the jujube sites without pasture.