农药亚致死剂量对小菜蛾及其天敌优姬蜂的影响

作者总结了在农业生态系统中农药亚致死剂量对害虫天敌影响的四条通径。在模拟农药—作物—小菜蛾—优姬蜂的生态系统中,系统地分析了农药—小菜蛾—优姬蜂种群动力学,用生命表技术,以控制效应(CE)来评判系统中农药亚致死剂量对小菜蛾和优姬蜂种群的影响,以及在农药亚致死剂量影响下,优姬蜂对小菜蛾种群的控制作用。结果表明,农梦特亚致死剂量对优姬蜂的控制效应大于对小菜蛾的控制效应,受农梦特亚致死剂量影响的优姬蜂仍能对小菜蛾种群起一定的控制作用。

SYSTEMIC ANALYSIS OF SUBLETHAL EFFECT OF INSECTICIDE ON PLUTELLA XYLOSTELLA AND ITS PARASITOID DIADEGMA EUCEROPHAGA

The paper deals with the systemic analysis of sublethal effect of insecticide on the population dynamics of the diamondback moth (DBM), Plutella xylostella and its para-sitoid Diadegma eucerophaga. The models of population dynamics of DBM and D. eu-cerophaga were mimiced in the simplified eco-systems with insecticide, cabage plants, insect pest and its natural enemy. The life table technique was used in the systemic analysis and the control efficiency(CE) was developped in this paper. The results showed that the CE of insecticide (Nomolt, teflubenzuron 25 ppm) on DBM was 68. 81%, while the CE of Nomolt on D. eucerophaga was 72- 27%, whereas the CE of D. eucerophaga on DBM was 59. 85% under the pressure of Nomolt. In addition, four pathes of the sub-lethal effects of insesticides on natural enemies were concluded in this paper.