Kibota T T, Courtney S P
Department of Biology, University of Oregon, 97403, Eugene, OR, USA.
Oecologia. 1991 Apr;86(2):251-260. doi: 10.1007/BF00317538.
Host selection by phytophagous insects is generally thought to be based on chemical or nutritional characteristics of the host. This is especially true for monophagous insects. However, many other factors may influence host choice. The present study examines host selection by Drosophila magnaquinaria, whose sole host is the yellow skunk cabbage, Lysichitum americanum. Utilization of skunk cabbage was tested relative to a set of alternative hosts. In the pre-alighting stage of host selection, skunk cabbage was found to be less attractive than tomato, cucumber, and commercial mushrooms. In pairwise oviposition tests, there were no differences among hosts. There were no differences in larval survivorship among skunk cabbage, tomato, cucumber, or Ramaria, and larvae developed into pupae earlier on tomato than on skunk cabbage. These results indicate that this monophagy is not based on characteristics of the host. We suggest that habitat selection is the more important factor in determining the association between D. magnaquinaria and skunk cabbage.
植食性昆虫对寄主的选择通常被认为是基于寄主的化学或营养特征。对于单食性昆虫来说尤其如此。然而，许多其他因素可能会影响寄主选择。本研究考察了大沼果蝇（Drosophila magnaquinaria）的寄主选择，其唯一寄主是黄臭菘（Lysichitum americanum）。相对于一组替代寄主，测试了黄臭菘的利用情况。在寄主选择的预先降落阶段，发现黄臭菘不如番茄、黄瓜和商业蘑菇有吸引力。在成对产卵试验中，各寄主之间没有差异。黄臭菘、番茄、黄瓜或红顶枝瑚菌（Ramaria）之间的幼虫存活率没有差异，并且幼虫在番茄上比在黄臭菘上更早发育成蛹。这些结果表明，这种单食性并非基于寄主的特征。我们认为，栖息地选择是决定大沼果蝇与黄臭菘之间关联的更重要因素。
