江淮地区早稻田害虫和天敌群落动态研究

对安徽江淮地区早稻田害虫和天敌群落动态进行了研究.共记录捕食性天敌16种,害虫12种.天敌优势种为草间小黑蛛、青翅蚁型隐翅虫、拟水狼蛛、四点亮腹蛛、八斑球腹蛛,害虫优势种为白背飞虱、褐飞虱、稻纵卷叶螟.草间小黑蛛、四点亮腹蛛、八斑球腹蛛、拟水狼蛛、白背飞虱主要分布于稻株中下部,青翅蚁型隐翅虫和褐飞虱主要分布于稻株下部,稻纵卷叶螟主要分布于稻株上部.群落多样性总体上较稳定,早稻生育后期略高于前期,均匀度是影响多样性的主要因素.以功能团为单位和以物种为单位的群落多样性指数呈高度正相关.群落特征在早稻分蘖期至乳熟期比较类似,但蜡熟期群落优势种突出,群落特征变化显著.

Dynamics of insect pest and natural enemy communities in early paddy fields in the Yangtze-Huaihe area

The dynamics of insect pest and natural enemy communities in early paddy fields in the Yangtze-Huaihe area of Anhui Province was studied.The results showed that there were totally 16 species of predatory enemies and 12 species of insect pests.The dominant species of predatory enemies were Erigonidium graminicola,Paederus fuscipes,Pirata subpiraticus,Singa pygmaea and Theridion octomaculatum,and the dominant species of insect pests were Sogatella furcifera,Nilaparvata lugens and Cnaphalocrocis medinalis.Among the dominant species,E.graminicola,S.pygmaea,T.octomaculatum,P.subpiraticus and S.furcifera were distributed mainly in the middle and lower parts of rice plants,P.fuscipes and N.lugens mainly in the lower part of rice plants,while C.medinalis mainly in the upper part of rice plants.The community diversity was rather stable and only a little higher in the late development period than in the early development of early rice.The principal factor affecting the diversity was species evenness.The community diversity indices based on species were significantly related to those based on guilds.The characteristics of the community were relatively analogous from the tillering stage to the milk stage of early rice,but changed obviously at the wax stage with the features of the dominant species getting conspicuous.