The walnut aphid species Chromaphis juglandicola Kalt. and Panaphis juglandis (Goeze) are destructive insect pests. Harmonia axyridis (Pall.) (Coleoptera: Coccinellidae) is the main predatory insect with a wide geographical distribution. The feeding behavior of the predator against the two different aphid species might influence bio-control efficacy in walnut orchards. Functional response of H. axyridis to various densities of the two aphid species was examined under temperatures ranging from 15 to 30 °C. The results showed that functional responses of H. axyridis towards C. juglandicola or P. juglandis fitted well with the Holling-II equation within the range of 15–30 °C. A greater biomass of aphids was consumed when the temperature increased from 15 to 30 °C. The predation efficacy of H. axyridis against C. juglandicola was greater than against P. juglandis, and the searching efficiency of H. axyridis against C. juglandicola was more effective than against P. juglandis. Moreover, predation rates against both aphid species decreased with increasing the H. axyridis density. This study showed that H. axyridis was an effective predator against the two walnut aphids. Increasing temperature (15–30 °C) increased prey consumption. Interference between individuals from increasing predator density had a negative impact on predation rate against the two aphid species.

中文翻译：

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温度对桃蚜（Chromaphis juglandicola Kalt ）上的Harmonia axyridis（Pall。）（鞘翅目：Coccinellidae）捕食的影响。和Panaphis juglandis（Goeze）

核桃蚜种Chromaphis juglandicola Kalt。和Panaphis juglandis（Goeze）是具破坏性的害虫。异色瓢虫（鞘翅目：球虫）是主要的掠食性昆虫，地理分布广泛。捕食者对两种不同蚜虫的摄食行为可能会影响核桃园的生物防治功效。在15至30°C的温度下检查了轴心菌对两种蚜虫各种密度的功能响应。结果表明，在15–30°C范围内，H。ayyridis对C. juglandicola或P. juglandis的功能响应与Holling-II方程拟合得很好。当温度从15升高到30°C时，会消耗更多的蚜虫生物量。轴心虫对C.的捕食效果 胡桃木大于对胡桃木，而木虱对胡桃木的搜索效率比胡桃木更有效。此外，随着蚜虫嗜血杆菌密度的增加，对两种蚜虫的捕食率均降低。这项研究表明，轴心线虫是对抗两种核桃蚜虫的有效捕食者。温度升高（15–30°C），猎物消耗增加。捕食者密度的增加对个体之间的干扰对两种蚜虫的捕食率均产生负面影响。蚜虫是对抗两种核桃蚜虫的有效捕食者。温度升高（15–30°C），猎物消耗增加。捕食者密度的增加对个体之间的干扰对两种蚜虫的捕食率均产生负面影响。蚜虫是对抗两种核桃蚜虫的有效捕食者。温度升高（15–30°C），猎物消耗增加。捕食者密度的增加对个体之间的干扰对两种蚜虫的捕食率均产生负面影响。