Data from: Linking plant genes to insect communities: identifying the genetic bases of plant traits and community composition

Community genetics aims to understand the effects of intraspecific genetic variation on community composition and diversity, thereby connecting community ecology with evolutionary biology. Thus far, research has shown that plant genetics can underlie variation in the composition of associated communities (e.g., insects, lichen, endophytes), and those communities can therefore be considered as extended phenotypes. This work, however, has been conducted primarily at the plant genotype level and has not identified the key underlying genes. To address this gap, we used genome-wide association mapping (GWAS) with a population of 445 aspen (Populus tremuloides) genets to identify the genes governing variation in plant traits (defense chemistry, bud phenology, leaf morphology, growth) and insect community composition. We found 49 significant SNP associations in 13 Populus genes that are correlated with chemical defense compounds and insect community traits. Most notably, we identified an early-nodulin like protein (ENODL) that was associated with insect community diversity and the abundance of interacting foundation species (ants and aphids). These findings support the concept that particular plant traits are the mechanistic link between plant genes and the composition of associated insect communities. In putting the "genes" into "genes to ecosystems ecology", this work enhances understanding of the molecular genetic mechanisms that underlie plant-insect associations and the consequences thereof for the structure of ecological communities.

群落遗传学（Community genetics）旨在阐明种内遗传变异对群落组成与多样性的影响，由此搭建起群落生态学与进化生物学之间的桥梁。迄今已有研究证实，植物遗传学可主导伴生群落（如昆虫、地衣、内生菌）的组成变异，因此这类群落可被视为延伸表型。然而，此类研究目前多局限于植物基因型层面，尚未明确其中发挥核心作用的关键基因。
为填补这一研究空白，我们以445株美洲颤杨（Populus tremuloides）基株构成的群体为材料，开展全基因组关联作图（GWAS）分析，筛选调控植物性状（防御化学物质、芽物候、叶片形态、生长特性）以及昆虫群落组成的基因。我们在13个杨属基因中鉴定出49个与化学防御物质及昆虫群落性状显著相关的单核苷酸多态性（SNP）关联位点。尤为值得关注的是，我们发现一种早期结瘤素样蛋白（ENODL），其与昆虫群落多样性以及相互作用的基石物种（蚂蚁与蚜虫）的丰度显著相关。
上述研究结果佐证了“特定植物性状是连接植物基因与伴生昆虫群落组成的机制性纽带”这一学术观点。本研究将“基因”维度纳入“基因-生态系统生态学”的研究框架，从而加深了我们对植物-昆虫共生关系背后的分子遗传机制，以及该机制对生态群落结构所产生影响的认知。