School of Natural Resources and Environment, University of Florida, Gainesville, FL, 32611, USA.
Department of Chemistry, United States Naval Academy, Annapolis, MD, 21402, USA.
Oecologia. 2021 Jun;196(2):317-329. doi: 10.1007/s00442-021-04866-2. Epub 2021 Feb 12.
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逸栽培的情况下提供益处，但其他植物已成为突出的入侵物种。更好地了解驯化如何改变影响物种克服入侵障碍能力的植物特征，可以提高入侵风险预测。我们探讨了美国广泛入侵物种（Lespedeza cuneata）的品种间叶片化学差异如何通过食草动物相互作用的差异以及与竞争能力的潜在权衡来影响入侵风险。在无选择的喂养生物测定中，与野生基因型和本地同属植物相比，一种普通的食草动物在喂食品种时表现更好，这表明与野生基因型相比，驯化的 L. cuneata 可能更容易受到食草动物的侵害。然而，在一个具有食草动物和竞争处理的温室综合实验中，所有品种的种子和生物量产生与野生基因型相似。与本地物种的竞争减少了所有 L. cuneata 类型的生产力，而单独的实验性食草动物则没有。我们还发现，L. cuneata 类型之间的叶片化学差异远小于根据驯化历史预期的差异。虽然生物测定的结果表明，如果食草动物种群在以品种为食时更快地扩张，那么品种的入侵风险可能更低，但我们没有发现证据表明品种在温室实验中对食草动物或与本地物种的竞争有不同的反应。总的来说，我们评估一个驯化物种入侵成功潜在因素的多管齐下的方法的结果表明，驯化并没有改变这种广泛入侵植物的入侵风险。
