异色瓢虫对苹果-蛇床草微景观中两种蚜虫的捕食功能反应及选择偏好性

为评估异色瓢虫Harmonia axyridis对苹果-蛇床草微景观中2种寄主上绣线菊蚜Aphis spiraecola和胡萝卜微管蚜Semiaphis heraclei的生物防治潜能，在实验室条件下测定异色瓢虫1~4龄幼虫和雌、雄成虫对2种蚜虫3~4龄若蚜的捕食功能反应、寻找效应以及捕食偏好性。结果表明，异色瓢虫1~4龄幼虫和雌、雄成虫对绣线菊蚜和胡萝卜微管蚜的捕食功能反应均符合Holling Ⅱ型功能反应类型，其中，雌成虫对绣线菊蚜的捕食能力最强，为411.284，雄成虫对胡萝卜微管蚜的捕食能力最强，为356.403； 2龄幼虫对绣线菊蚜的瞬时攻击率最大，为1.231，3龄幼虫对胡萝卜微管蚜的瞬时攻击率最大，为1.277。异色瓢虫各虫态对绣线菊蚜和胡萝卜微管蚜的寻找效应均随着蚜虫密度的升高而降低。当2种蚜虫共存且总密度为60头/皿时，不同密度比例下异色瓢虫对2种蚜虫均无显著偏好性；当总密度为240头/皿，绣线菊蚜与胡萝卜微管蚜的密度比例为1:5、2:4、3:3和4:2时异色瓢虫对绣线菊蚜表现出显著的偏好性，而在密度比例为1:5、3:3和4:2时异色瓢虫对胡萝卜微管蚜表现出显著的负偏好性。表明异色瓢虫对苹果-蛇床草微景观中绣线菊蚜的防控潜能更好。

Functional response and predation preference of multicolored Asian lady beetle Harmonia axyridis to two aphids in the micro-landscape of apple and Monnier''s snowparsley Cnidium monnieri

In order to assess the biological control potential of multicolored Asian lady beetle Harmonia axyridis to spirea aphid Aphis spiraecola and celery aphid Semiaphis heraclei available in the microlandscape of apple and Monnier''s snowparsley Cnidium monnieri, the predation effect, searching efficiency and predation preference of H. axyridis to A. spiraecola and S. heraclei were studied under laboratory conditions. The results showed that the functional response of the 1st-4th instar larvae, female and male adults of H. axyridis to the 3rd-4th instar nymphs of A. spiraecola and S. heraclei fitted well with the Holling II model. The predation capacity of female adults of H. axyridis against A. spiraecola was the strongest, which was 411.284, while the predation capacity of male adults of H. axyridis to S. heraclei was the strongest (356.403). The instantaneous attack rate of the 2nd instar nymph of H. axyridis against A. spiraecola was the strongest, which was 1.231, while the instantaneous attack rate of the 3rd instar nymph of H. axyridis against S. heraclei was the strongest (1.277). The searching efficiency of H. axyridis for A. spiraecola and S. heracleid decreased with increasing prey densities. Under the condition of coexistence of A. spiraecola and S. heraclei, when the total density was 60 individuals per dish, H. axyridis female adults had no significant preference for both aphid species at different ratios; when the total density was 240 individuals per dish, H. axyridis female adults showed significant positive preference for A. spiraecola in the ratios (A. spiraecola:S. heraclei) of 1:5, 2:4, 3:3 and 4:2, but showed negative preference for S. heraclei in the ratios of 1:5, 3:3 and 4:2. This study suggested that H. axyridis has strong control potential against A. spiraecola in the micro-landscape of apple and functional plant.