Niche separation between competing species is a central issue in ecology. As two of the most important pests worldwide of cereal production, Rhopalosiphum padi primarily dominates stems and basal leaves of wheat plants, whereas Sitobion avenae is common on the upper leaves and ears. Here, we investigated this microniche separation by considering effects of food resources and microclimates on the behavior and performance of R. padi and S. avenae on tissues from individual wheat seedlings. Wheat leaves provided favorable food for both aphid species and this tissue had high free amino acid and low soluble sugar compared with wheat stems. Both species preferred microclimates in the lower area of the seedlings where humidity was relatively higher and temperatures were relatively lower. In terms of performance, R. padi was more sensitive to microclimate effects than S. avenae, while the latter species was relatively more sensitive to limiting food resources. These factors may help explain why R. padi is relatively more common on lower microhabitats of seedlings, in contrast to S. avenae, contributing to the microspatial distribution of these species more generally. This information contributes to a better understanding of the relationship between these aphids and their host plants, which may assist in control strategies targeting these aphids.

竞争物种之间的生态位分离是生态学的中心问题。作为全球谷物生产中最重要的两种害虫，红景天主要控制小麦植株的茎和基生叶，而Sitobion avenae常见于上叶和穗。在这里，我们通过考虑食物资源和小气候对R. padi和S. avenae的行为和性能的影响，研究了这种小生境分离。在个别小麦幼苗的组织上。小麦叶片为两种蚜虫都提供了有利的食物，与小麦茎相比，该组织具有较高的游离氨基酸和较低的可溶性糖。在湿度相对较高而温度相对较低的幼苗下部区域，这两个物种都更喜欢小气候。在性能方面，R。padi对小气候的影响比S. avenae更敏感，而后者对限制食物资源相对更敏感。这些因素可能有助于解释为什么R. PADI是对幼苗的下小生境比较多见，而相比之下，麦长管蚜，更广泛地促进了这些物种的微空间分布。这些信息有助于更好地了解这些蚜虫及其寄主植物之间的关系，这可能有助于针对这些蚜虫的控制策略。