Effect of plant chemical variation and mutualistic ants on the local population genetic structure of an aphid herbivore

1.Plants exhibit impressive genetic and chemical diversity, not just between species but also within species, and the importance of plant intraspecific variation for structuring ecological communities is well known. When there is variation at the local population level, this can create a spatially‐heterogeneous habitat for specialized herbivores potentially leading to non‐random distribution of individuals across host‐plants.

2.Plant variation can affect herbivores directly and indirectly via a third species, resulting in variable herbivore growth rates across different host plants. Herbivores also exhibit within‐species variation, with some genotypes better adapted to some plant variants than others.

3.We genotyped aphids collected across two years from a field site containing ~200 patchily‐distributed host plants that exhibit high chemical diversity. The distribution of aphid genotypes, their ant mutualists, and other predators was assessed across the plants.

4.We present evi...

1. 植物不仅在物种间，更在物种内展现出显著的遗传与化学多样性；植物种内变异（intraspecific variation）对生态群落结构塑造的重要性已得到学界广泛认知。当局域种群存在遗传变异时，可为专食性植食动物创造空间异质性生境，进而可能导致昆虫个体在寄主植物间呈现非随机分布格局。
2. 植物变异可通过第三类物种对植食动物产生直接与间接影响，使得不同寄主植物上的植食动物生长速率存在显著差异。植食动物自身同样存在种内变异，部分基因型（genotype）相较于其他基因型更适配特定的植物变异类型。
3. 我们对连续两年从某野外样地采集的蚜虫进行了基因分型，该样地内约有200株呈斑块状分布的寄主植物，这些寄主植物具有较高的化学多样性。我们还调查了蚜虫基因型、其互利共生蚂蚁（ant mutualists）以及其他捕食者在各寄主植物上的分布情况。
4. 本研究展示了实证……