Most non-native domesticated plants provide benefits without escaping cultivation, but others have become prominent invaders. A better understanding of how domestication might alter plant traits that influence the ability of species to overcome barriers to invasion could improve invasion risk predictions. We explored how variation in foliar chemistry among cultivars of a widespread invader in the U.S. (Lespedeza cuneata) might influence invasion risk through differences in herbivore interactions and a potential tradeoff with competitive ability. In a no-choice feeding bioassay a generalist herbivore performed better when fed cultivars compared to wild genotypes and native congeners, suggesting domesticated L. cuneata may be more vulnerable to herbivory compared to wild genotypes. However, in a factorial greenhouse experiment, with treatments of herbivory and competition, all cultivars had similar seed and biomass production as the wild genotype. Competition with native species reduced productivity of all L. cuneata types, while experimental herbivory alone did not. We also found far less variation in foliar chemistry among L. cuneata types than expected based on domestication history. While our findings from the bioassay suggest potentially lower invasion risk for cultivars if herbivore populations expand more rapidly when feeding on cultivars, we did not find evidence that cultivars had different responses to herbivory or competition with native species in the greenhouse experiment. Altogether, the findings from our multi-pronged approach for evaluating potential factors underlying invasion success of a domesticated species indicate that domestication has not altered invasion risk of this widespread plant invader.

大多数非本地驯化植物在不逃避耕种的情况下提供收益，但其他植物已成为重要的入侵者。更好地了解驯化如何改变植物性状，从而影响物种克服入侵壁垒的能力，可以改善入侵风险的预测。我们探讨了在美国（Lespedeza cuneata）一个广泛侵略者的品种之间叶化学的变化如何通过草食动物相互作用的差异以及竞争能力的潜在折衷来影响入侵风险。在无选择饲喂生物测定中，与野生基因型和本地同类物相比，饲喂栽培品种的通配草食动物表现更好，这表明驯养的库氏乳杆菌与野生基因型相比，草食动物可能更易受到攻击。然而，在一项因子分解温室试验中，通过食草和竞争处理，所有品种的种子和生物量产量均与野生基因型相似。与本地物种的竞争降低了所有楔形藻的生产力，而仅实验性草食动物却没有。我们还发现库氏乳杆菌的叶片化学变化很小类型比预期的归化历史。虽然我们从生物测定中获得的结果表明，如果以食草动物为食时食草动物种群的增长更快，则对食草植物的入侵风险可能会降低，但我们没有发现证据表明，在温室实验中，食草动物对食草植物的反应或与本地物种的竞争不同。总之，我们采用多管齐下的方法来评估潜在驯化物种入侵成功的潜在因素表明，驯化并未改变这种广泛植物入侵者的入侵风险。