Data from: Host-adapted aphid populations differ in their migratory patterns and capacity to colonize crops

1. Although phytophagous insects can vary genetically in host use and exhibit long-range movements, the combined implications of these phenomena for pest management have received limited attention.
2. To address this, we surveyed the genetic diversity of pea aphid Acyrthosiphon pisum using twelve microsatellite loci and assessed host association patterns and annual movement from a putative source region (Columbia River Basin) to the Palouse region of northern Idaho and western Washington, where the aphid is a pest of pea Pisum sativum.
3. A total of 320 identified unique genotypes clustered into four genetic groups, with two host plant associations: alfalfa Medicago sativa (three genetic groups), and pea Pisum sativum and vetch Vicia villosa (one genetic group). All four genetic groups occurred in the Columbia River Basin and in migrant aphids collected in pan traps during spring colonization in the Palouse during two years of this study. Patterns of group arrival on the Palouse were spatially structured early in the season, consistent with differing migration patterns. Despite genetic diversity of migrants, a single genetic group became predominant in pea crops each year.
4. Clonal laboratory colonies of pea aphids established from field-collected specimens and representing the two predominant genetic groups exhibited reciprocal performance trade-offs, with alfalfa a poor host for a pea-associated aphid genotype and vice versa.
5. Synthesis and applications. Annual spring migrants of pea aphids in the pea production region of the Palouse are genetically diverse, with different host plant affinities consistent with origination from source populations in the Columbia River Basin. As the season progresses, a single genetic group adapted to pea becomes predominant in the crop. Management of pea aphid in the Palouse will be improved by monitoring the temporal and spatial variation of specific genetic groups of the aphid arriving as immigrants at the during each crop season, providing this information to producers and adjusting estimates of risk of crop damage accordingly. The principle could apply to other pest species with host-adapted populations that colonize crops on an annual basis.

1. 尽管植食性昆虫（phytophagous insects）在寄主利用方面存在遗传变异，且可进行长距离移动，但这两种现象综合起来对害虫治理的潜在影响尚未得到足够关注。
2. 为填补这一研究空白，本研究利用12个微卫星位点（microsatellite loci）对豌豆蚜（Acyrthosiphon pisum）的遗传多样性进行了检测，并评估了其寄主关联模式以及从推测的源种群区域——哥伦比亚河流域（Columbia River Basin）向爱达荷州北部与华盛顿州西部的帕卢斯（Palouse）地区的年度迁移规律；帕卢斯地区的豌豆蚜是豌豆（Pisum sativum）的重要农业害虫。
3. 本研究共鉴定得到320个独特基因型，经聚类可划分为4个遗传类群，且存在两类寄主植物关联：一类与紫花苜蓿（Medicago sativa）相关（包含3个遗传类群），另一类与豌豆（Pisum sativum）及长柔毛野豌豆（Vicia villosa）相关（仅含1个遗传类群）。哥伦比亚河流域以及本研究两年间春季帕卢斯地区作物定植期通过诱捕盘（pan traps）采集的迁飞蚜种群中，均检测到全部4个遗传类群。季初帕卢斯地区的类群迁入模式具有空间结构特征，与不同的迁飞规律相符。尽管迁飞蚜种群存在遗传多样性，但每年豌豆田中的优势类群均为单一遗传类群。
4. 从田间采集标本建立的豌豆蚜无性系实验室种群（涵盖两类优势遗传类群）表现出互作适合度权衡：与豌豆关联的蚜基因型在紫花苜蓿上的适合度表现较差，反之亦然。
5. 综合与应用。帕卢斯豌豆产区的豌豆蚜春季年度迁飞种群具有丰富的遗传多样性，其不同的寄主植物亲和性与哥伦比亚河流域的源种群起源相符。随着季节推进，适应豌豆的单一遗传类群会成为田间优势类群。通过监测每个作物季迁入的蚜虫特定遗传类群的时空动态，向种植者通报相关信息并据此调整作物受害风险评估，可优化帕卢斯地区豌豆蚜的害虫治理工作。该原理同样适用于其他具有寄主适应性种群（host-adapted populations）、且每年迁飞定植作物的害虫物种。