南方小花蝽成虫对二斑叶螨的捕食作用研究

Predation of OriussimilisAdult on Tetranychus urticae

为探明南方小花蝽成虫对二斑叶螨的控制效果,在实验室条件下将采自田间的南方小花蝽饲养一代,就其雌成虫对二斑叶螨雌成螨、若螨、卵3个螨态的选择性、捕食作用和干扰反应进行了研究.结果表明:南方小花蝽成虫对二斑叶螨的选择性从大到小依次为雌成螨、若螨、卵.南方小花蝽对二斑叶螨不同螨态的捕食功能反应均符合HollingⅡ型方程,在一定猎物密度范围内,南方小花蝽捕食量随着猎物密度的增加而增大,寻找效应随着猎物密度的增加而降低.在相同猎物密度下,随着南方小花蝽雌成虫密度的增大,其捕食作用率相应地降低,表明其捕食作用有较强的种内干扰反应.捕食作用率E与南方小花蝽雌成虫密度P的关系为E=0.339 0P-0.362 4,经卡方检验雌成虫的捕食作用率实测值与理论值相符,该模型方程能很好地反映雌成虫自身密度的干扰程度.分摊竞争强度I与南方小花蝽成虫密度P的关系为I=0.108 0logP-0.057 9.

Prey preference,functional response and interference of the predator Orius similis on female adults,nymphs and eggs of Tetranychus urticae were studied in the laboratory conditions in order to learn the control efficiency of the O.similis to T.urticae.The results showed that O.similis prefer to feed on adults than on nymphs or larvae of T.urticae.The functional response of O.similis on different stages of T.urticae well fitted the model of Holling Ⅱtype.Predation capacity of O.similis adult to T.urticae increased with the increment of density of T.urticae,however searching rate decreased.At the same prey density,predation rate of O.similis decreased with the increasing of its density.Intraspecific interference was found in the experiment.The relationship between predation ration（E）and natural enemy density（P）was described by equation of E =0.339 0P-0.362 4,and the relationship between intensity of scrambling competition（I）and the density of O.Similis（P）was I=0.108 0logP-0.057 9.The Hassell model could reflect their functional responses.