Data from: Hybridization of an invasive shrub affects tolerance and resistance to defoliation by a biological control agent

Evolution has contributed to the successful invasion of exotic plant species in their introduced ranges, but how evolution affects particular control strategies is still under evaluation. For instance, classical biological control, a common strategy involving the utilization of highly specific natural enemies to control exotic pests, may be negatively affected by host hybridization because of shifts in plant traits, such as root allocation or chemical constituents. We investigated introgression between two parent species of the invasive shrub tamarisk (Tamarix spp.) in the western U.S., and how differences in plant traits affect interactions with a biological control agent. Introgression varied strongly with latitude of origin and was highly correlated with plant performance. Elevated levels of T. ramosissima introgression resulted in both higher investment in roots and tolerance to defoliation and less resistance to insect attack. Because tamarisk hybridization occurs predictably on the western U.S. landscape, managers may be able to exploit this information to maximize control efforts. Genetic differentiation in plant traits in this system underpin the importance of plant hybridization and may explain why some biological control releases are more successful than others.演化助力外来植物物种在其入侵范围内成功定殖，但演化如何影响特定的防控策略仍有待评估。例如，经典生物防治作为一种利用高度专一性天敌对外来有害生物进行防控的常用策略，可能会因寄主杂交引发的植物性状改变（如根系分配或化学组分变化）而受到负面影响。本研究针对美国西部入侵灌木柽柳（Tamarix spp.）的两个亲本物种间的渐渗作用展开调查，并探究植物性状差异如何影响其与生物防治天敌的互作关系。渐渗程度随原产地纬度呈现显著差异，且与植物生长表现高度相关。较高水平的T. ramosissima渐渗，不仅提升了植物的根系资源投入与耐落叶性，还降低了其对昆虫取食的抗性。由于柽柳杂交事件在美国西部区域具有可预测性，管理者可利用该信息以最大化防控成效。该系统中植物性状的遗传分化，凸显了植物杂交的重要性，同时或可解释为何部分生物防治释放项目的成效优于其他项目。