利用功能反应模型评价球孢白僵菌对东亚小花蝽捕食二斑叶螨的影响

【目的】天敌昆虫和生防菌剂的应用都是害虫生物防治的有效手段，在生产中通过两者联合进行害虫的生物防治具有极强的应用前景和潜在的防控增效作用，然而生防菌对天敌的安全性评价是必不可少的。本研究旨在评估球孢白僵菌Beauveria bassiana与东亚小花蝽Orius sauteri联合应用进行害虫生物防治的可行性。【方法】测定了东亚小花蝽5龄若虫经2种不同浓度的球孢白僵菌孢悬液(常规浓度: 1×10⁷孢子/mL; 低浓度: 5×10³孢子/mL)和孢子粉(1×10⁷孢子/头)处理后成虫羽化率以及经上述处理后的东亚小花蝽5龄若虫对不同密度下的二斑叶螨Tetranychus urticae雌成螨的捕食能力。【结果】东亚小花蝽5龄若虫经白僵菌孢子粉(1×10⁷孢子/头)处理后，成虫羽化率显著降低，其余处理的成虫羽化率与对照无显著差异。3个处理组中东亚小花蝽5龄若虫对二斑叶螨雌成螨的捕食功能反应均符合HollingII型，搜寻效应随猎物密度增加逐渐降低。经低浓度球孢白僵菌孢悬液(5×10³孢子/mL)处理的东亚小花蝽5龄若虫的理论日最大捕食量(N_a-max)最高，猎物处理时间最短(T_h)，搜寻效应回归线随猎物密度增加下降趋势最小；而球孢白僵菌孢子粉处理的东亚小花蝽5龄若虫理论日最大捕食量最低，猎物处理时间最长。【结论】低浓度的白僵菌孢悬液对东亚小花蝽5龄若虫对二斑叶螨雌成螨的捕食能力无影响，而孢子粉对该天敌5龄若虫捕食二斑叶螨雌成螨造成不利影响。本研究初步证明低浓度白僵菌孢悬液与东亚小花蝽联合应用防控二斑叶螨具有可行性。

Evaluation of the effects of Beauveria bassiana on the predation of Tetranychus urticae (Acari: Tetranychidae) by Orius sauteri (Hemiptera: Anthocoridae) using functional response model

【Aim】 The application of natural enemies and biocontrol bacteria are effective means of pest biological control, and the combined application of the two kinds of agents have strong application prospects and potential of synergistic effect on biological control in the production. However, it is essential to evaluate the safety of biocontrol bacteria on natural enemies. This study aims to assess the biocontrol potential of combined release of Beauveria bassiana and Orius sauteri for biological control of pests. 【Methods】 We measured the emergence rate of O. sauteri adults after the 5th instar nymphs were treated with two different concentrations of B. bassiana spore suspensions (routine concentration: 1×10⁷ conidia/mL; low concentration: 5×10³ conidia/mL) and spore powder (1×10⁷ conidia/individual) and the predation ability of the 5th instar nymphs of O. sauteri