Interdisciplinary Graduate School of Science and Technology, Shinshu University, Asahi, Matsumoto, Nagano, Japan.
Graduate School of Fisheries and Environmental Sciences, Nagasaki University, Bunkyo, Nagasaki, Nagasaki, Japan.
J Insect Sci. 2020 Sep 1;20(5). doi: 10.1093/jisesa/ieaa103.
About 10% of aphid species show host alternation. These aphids migrate between primary and secondary host plant species in spring and autumn. Host alternation has not been observed in subfamily Lachninae, although it has been suggested on the basis of circumstantial evidence that Stomaphis japonica (Takahashi) may alternate its host between Quercus serrata (Murray) and Quercus acutissima (Carruth). However, a molecular phylogenetic study has indicated that the Stomaphis individuals feeding on these two plant species belong to two different lineages and aphids feeding on Q. acutissima and Pinus densiflora (Sieb. & Zucc.) belong to the same lineage. Here, we examined host alternation in Stomaphis species by comparing molecular phylogenetic identities, morphological features, and life cycles. The molecular analysis and morphological examination showed that aphids feeding on Q. acutissima were the same as those feeding on P. densiflora, whereas aphids feeding on Q. serrata were different from those feeding on Q. acutissima or on P. densiflora. Furthermore, winged aphids were observed on both Q. acutissima and P. densiflora in autumn, but we did not observe winged aphids on Q. serrata. These results indicate that Stomaphis (Walker) individuals feeding on Q. serrata and Q. acutissima belong to two species, one that feeds year-round on Q. serrata, and another, heteroecious species that feeds on P. densiflora as a primary host and on Q. acutissima as a secondary host. This study documents host alternation in subfamily Lachninae for the first time and discusses the acquisition of host alternation by Stomaphis from evolutionary and ecological perspectives.
约 10%的蚜虫物种表现出宿主交替现象。这些蚜虫在春季和秋季在主要和次要宿主植物之间迁徙。在 Lachninae 亚科中尚未观察到宿主交替现象，尽管根据间接证据表明，Stomaphis japonica (Takahashi) 可能在 Quercus serrata (Murray) 和 Quercus acutissima (Carruth) 之间交替宿主。然而，一项分子系统发育研究表明，在这两种植物上取食的 Stomaphis 个体属于两个不同的谱系，取食 Q. acutissima 和 Pinus densiflora (Sieb. & Zucc.) 的蚜虫属于同一谱系。在这里，我们通过比较分子系统发育身份、形态特征和生活史来检验 Stomaphis 物种的宿主交替现象。分子分析和形态学检查表明，取食 Q. acutissima 的蚜虫与取食 P. densiflora 的蚜虫相同，而取食 Q. serrata 的蚜虫与取食 Q. acutissima 或 P. densiflora 的蚜虫不同。此外，在秋季观察到取食 Q. acutissima 和 P. densiflora 的有翅蚜虫，但未在 Q. serrata 上观察到有翅蚜虫。这些结果表明，取食 Q. serrata 和 Q. acutissima 的 Stomaphis (Walker) 个体属于两个物种，一个全年取食 Q. serrata，另一个为异宿主物种，以 P. densiflora 为主要宿主，以 Q. acutissima 为次要宿主。本研究首次记录了 Lachninae 亚科的宿主交替现象，并从进化和生态角度讨论了 Stomaphis 获得宿主交替的情况。
