Dinesh A S, Venkatesha M G
Department of Zoology, Bangalore University, Jnanabharathi, Bengaluru 560056, Karnataka, India.
Bull Entomol Res. 2014 Feb;104(1):48-55. doi: 10.1017/S0007485313000485. Epub 2013 Sep 18.
Spalgis epius and Cryptolaemus montrouzieri are the two potential predators of different species of mealybugs. However, the mode of their interactions is not known to use these predators together in the field. Hence, we investigated on the possible interactions i.e., cannibalism, intraguild predation (IGP) and competition between the predators in the presence and absence of prey Planococcus citri. In the presence of prey, no cannibalism and predation were observed in both S. epius and C. montrouzieri larvae. A pair of S. epius larvae consumed significantly more number of mealybugs than one S. epius/C. montrouzieri larva or a pair of C. montrouzieri larvae. The predation of S. epius larva by C. montrouzieri larva was significantly more than the predation of C. montrouzieri by S. epius. Conspecific and interspecific egg predation was absent both in S. epius and C. montrouzieri. Cannibalism in C. montrouzieri was more than that in S. epius. The study indicated that C. montrouzieri larvae can be used as an additive along with voracious S. epius larvae under abundant prey population. IGP was asymmetric between the two predators in the absence of prey. Both S. epius and C. montrouzieri larvae can maintain a stable coexistence when prey is abundantly available, however, in the complete absence of prey C. montrouzieri may dominate the guild. This study provides an insight into the possible complex inter- and intraspecific predatory phenomena in the field to use these two predators in the biological control of mealybugs.
斯氏花蝽和孟氏隐唇瓢虫是粉蚧不同物种的两种潜在捕食者。然而，尚不清楚它们在田间共同使用这些捕食者时的相互作用模式。因此，我们研究了在有和没有猎物柑橘臀纹粉蚧的情况下，捕食者之间可能的相互作用，即同类相食、种内捕食（IGP）和竞争。在有猎物的情况下，斯氏花蝽和孟氏隐唇瓢虫幼虫均未观察到同类相食和捕食现象。一对斯氏花蝽幼虫消耗的粉蚧数量明显多于一只斯氏花蝽/孟氏隐唇瓢虫幼虫或一对孟氏隐唇瓢虫幼虫。孟氏隐唇瓢虫幼虫对斯氏花蝽幼虫的捕食明显多于斯氏花蝽对孟氏隐唇瓢虫的捕食。斯氏花蝽和孟氏隐唇瓢虫均不存在同种和异种卵捕食现象。孟氏隐唇瓢虫的同类相食现象比斯氏花蝽更严重。研究表明，在猎物数量充足的情况下，孟氏隐唇瓢虫幼虫可与贪婪的斯氏花蝽幼虫一起作为添加剂使用。在没有猎物的情况下，两种捕食者之间的种内捕食是不对称的。当猎物大量存在时，斯氏花蝽和孟氏隐唇瓢虫幼虫都能保持稳定共存，然而，在完全没有猎物的情况下，孟氏隐唇瓢虫可能在群落中占主导地位。这项研究为在田间利用这两种捕食者进行粉蚧生物防治时可能存在的复杂种间和种内捕食现象提供了见解。
