Zhou Aiming, Lu Yongyue, Zeng Ling, Xu Yijuan, Liang Guangwen
Red Imported Fire Ant Research Center, South China Agricultural University, Guangzhou 510642, People's Republic of China.
Environ Entomol. 2013 Apr;42(2):247-52. doi: 10.1603/EN12168.
Mutualism is a common and important ecological phenomenon characterized by beneficial interaction between two species. Red imported fire ants, Solenopsis invicta Buren, tend honeydew-producing hemipteran insects and reduce the activity of these insects' enemies. Ant-hemipteran interactions frequently exert positive effects on the densities of hemipterans. We tested the hypothesis that ant tending can increase the densities of the mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), and reduce the densities of the mealybug's predatory and parasitic enemies, the lady beetle, Menochilus sexmaculata Fabricius (Coleoptera: Coccinellidae), and the parasitoid wasp, Aenasius bambawalei Hayat (Hymenoptera: Encyrtidae). We found that more ants foraged on mealybug-infested hibiscus plants than on mealybug-free plants. The number of foraging ants on plants infested with high densities of mealybugs (62.5 ants per plant) was nearly six times that on mealybug-free plants (10.2 ants per plant). Experiment results showed that ant tending significantly increased the survival of mealybugs: if predatory and parasitic enemies were present, the survival of mealybugs tended by fire ants was higher than that in the absence of tending ants. Furthermore, this tending by fire ants significantly decreased the survival of lady beetle larvae. However, no apparent effect was observed on the survival of parasitoid.
互利共生是一种常见且重要的生态现象，其特征是两个物种之间存在有益的相互作用。红火蚁（Solenopsis invicta Buren）会照料分泌蜜露的半翅目昆虫，并降低这些昆虫天敌的活动。蚂蚁与半翅目昆虫之间的相互作用常常对半翅目昆虫的密度产生积极影响。我们检验了这样一个假设：蚂蚁的照料能够增加粉蚧（Phenacoccus solenopsis Tinsley，半翅目：粉蚧科）的密度，并降低粉蚧的捕食性和寄生性天敌的密度，这些天敌包括瓢虫（Menochilus sexmaculata Fabricius，鞘翅目：瓢虫科）和寄生蜂（Aenasius bambawalei Hayat，膜翅目：恩蚜小蜂科）。我们发现，相比没有粉蚧的植物，更多的蚂蚁在有粉蚧的芙蓉属植物上觅食。在高密度粉蚧侵染的植物上觅食的蚂蚁数量（每株植物62.5只蚂蚁）几乎是没有粉蚧的植物上（每株植物10.2只蚂蚁）的六倍。实验结果表明，蚂蚁的照料显著提高了粉蚧的存活率：如果存在捕食性和寄生性天敌，被红火蚁照料的粉蚧的存活率高于没有蚂蚁照料的情况。此外，红火蚁的这种照料显著降低了瓢虫幼虫的存活率。然而，未观察到对寄生蜂存活率有明显影响。
