不同猎物及密度对巴氏新小绥螨和拉戈钝绥螨同类相残和集团内捕食作用的影响

明确不同猎物及密度下巴氏新小绥螨Neoseiulus barkeri与拉戈钝绥螨Amblyseius largoensis(Muma)的同类相残和集团内捕食作用,为其协同应用控制橡胶树害螨提供依据.在室温27±1℃、湿度75％±5％、光周期12 L∶12D 条件下,以六点始叶螨 Eotetranvchus sexmac...

Effects of prey species and density on cannibalism and intraguild predation of predacious mites Neoseiulus barkeri and Amblyseius largoensis

The study aims to clarify the cannibalisms and intraguild predations of Neoseiulus barkeri and Amblyseius largoensis with different spider mite species and densities. This knowledge will allow us to establish a reasonable predacious mite combination for biological control of major spider mites on rubber trees. Under the condition of 27°C, 70%±5% humidity, and photoperiod 12 L: 12 D, the predilections between spider mite predation and intraguild predation of N. barkeri and A. largoensis were assessed. Afterwards, the effects of spider mite species and density on intraguild predations and cannibalisms of two predators were evaluated. The predation preferences and consuming times for spider mite predations and intraguild predations of two predacious mites were different. N. barkeri preferred always spider mites, the survival rate of A. largoensis is more than 80.00% compared to all spider mites. However, A. largoensis preferred spider mites, only when Eotetranychus sexmaculatus or Oligonychus biharen existed. In case, Eutetranychus orientalis existed, it preferred to prey on N. barkeri (survival rate: 26.67%). In the intraguild predation interaction of two predacious mites, A. largoensis seems the predator and N. barkeri was likely the prey. The cannibalisms of N. barkeri and A. largoensis significantly decreased when spider mites existed, especially when sufficient numbers of E. sexmaculatus and O. biharen were provided to N. barkeri and A. largoensis, respectively, the cannibalisms decreased 68.85% and 62.90% compared to spider mite absent. Similarly, the intraguild predations of N. barkeri and A. largoensis decreased when spider mites existed, especially when sufficient numbers of O. biharen and E. sexmaculatus were provided to N. barkeri and A. largoensis, the intraguild predations of N. barkeri and A. largoensis decreased 80.00% and 69.44% compared to spider mite absent. However, the density of E. orientalis did affected the intraguild predation of A. largoensis on N. barkeri. When sufficient number of E. orientalis was provided, the predation number of A. largoensis on N. barkeri decreased only 20.83% compared to spider mite absent. When the spider mites E. sexmaculatus and O. biharen existed, both predacious mites preferred spider mites than intraguild predation. The increase of spider mite densities could decrease both cannibalisms and intraguild predations of the two predacious mites. However, E. orientalis and its density have only limited influence on the intraguild predation of A. largoensis on N. barkeri.