Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is an important biocontrol agent in native region of Asia, while its high propensity for cannibalism causes great obstacles in mass production. Provisioning obstructs in rearing containers could decrease the cannibalism of ladybird beetles. In this study, three different patterns of obstructs (Con-A, Con-B, and Con-C) were designed and equipped in plastic Petri dishes (95.38 cm3) as rearing units, and their efficiency for H. axyridis larval survival was tested. The potential of the high-density rearing was then evaluated using the optimal units with 16, 24, or 32 larvae per unit (named 16-L, 24-L, or 32-L, respectively). Larval survivals in obstructs-equipped units were generally higher than those in control, and significantly increased with the Con-C units (39.8% versus 74.2% at adult stage). With the Con-C units, the survivals were significantly higher at 16-L density (82.5%) than those at 24-L density (62.5%), but both were non-significantly different from those at 32-L density (70.0%). The weights of newly emerged adults (fit with the expected sex ratio of 1:1) at the higher densities were lower than those at 16-L density. The results demonstrate that H. axyridis can be reared at a higher density (≈ 0.336 larvae/cm3) in a constrained unit and highlight the effects of obstructs in reducing cannibalism and improving insect survivals.

中文翻译：

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配备障碍物的设备可减少食人症，并提高球瓢虫（Harmonia axyridis）（鞘翅目：球藻）的幼虫存活率

异轴和谐虫（Pallas）（鞘翅目：球虫科）是亚洲本土地区的重要生物防治剂，而其食人性的高倾向给大规模生产带来了巨大障碍。在饲养容器中设置障碍物可以减少瓢虫的食人性。在这项研究中，设计了三种不同模式的障碍物（Con-A，Con-B和Con-C），并在塑料培养皿（95.38 cm3）中作为饲养单元进行了装备，并测试了它们对木虱幼虫存活的效率。 。然后使用每单位16个，24个或32个幼虫的最佳单位（分别命名为16-L，24-L或32-L）评估高密度饲养的潜力。装有阻塞物的单位的幼虫存活率通常高于对照组，而使用Con-C单位的幼虫存活率则显着增加（成年时分别为39.8％和74.2％）。使用Con-C装置时，在16升密度下的存活率（82.5％）显着高于在24升密度下的存活率（62.5％），但与32升密度下的存活率（70.0％）无显着差异。 ）。密度较高时，新出现的成年人的体重（符合预期的1：1性别比）比16升密度时的体重要低。结果表明，可以在一个受约束的单元中以较高的密度（约0.336幼虫/ cm3）饲养轴心菌，并突出显示了障碍物在减少食人性和提高昆虫存活率方面的作用。1）在较高密度下比在16 L密度下低。结果表明，可以在一个受约束的单元中以较高的密度（约0.336幼虫/ cm3）饲养轴心菌，并突出显示了障碍物在减少食人性和提高昆虫存活率方面的作用。1）在较高密度下比在16 L密度下低。结果表明，可以在一个受约束的单元中以较高的密度（约0.336幼虫/ cm3）饲养轴心菌，并突出显示了障碍物在减少食人性和提高昆虫存活率方面的作用。