Despite their near ubiquity across global ecosystems, the underlying mechanisms contributing to the success of invasive plants remain largely unknown. In particular, ecophysiological traits, which are fundamental to plants’ performance and response to their environment, are poorly understood with respect to geographic and climate space. We evaluated photosynthetic trait variation among populations, ecotypes and home climates (i.e. the climates from the locations they were collected) of the widespread and expanding invader Johnsongrass (Sorghum halepense). We found that populations vary in the maximum net photosynthetic flux and the light-saturated net photosynthetic rate, and that agricultural and non-agricultural ecotypes vary in apparent quantum yield and water-use efficiency (WUE). We also found that populations from warmer home climates had lower dark respiration rates, light compensation points and WUEs. As Johnsongrass expands across the USA the abiotic and biotic environments are driving variation in its genetics, phenotypes and its underlying physiology. Our study demonstrates the importance of evaluating physiological traits in invasive plants, especially as they relate to home climates.

中文翻译：

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种内，生态型和家庭气候变化对广泛入侵的约翰逊草光合特性的影响。

尽管它们在全球生态系统中几乎无处不在，但促成入侵植物成功的基本机制仍然未知。特别是，对于植物的性能和对环境的反应至关重要的生态生理特性，在地理和气候空间方面知之甚少。我们评估了广泛入侵的约翰逊草（高粱halepense）的种群，生态类型和家庭气候（即从收集地点的气候）之间的光合特性差异。）。我们发现种群的最大净光合通量和光饱和净光合速​​率有所不同，而农业和非农业生态型的表观量子产量和水分利用效率（WUE）也有所不同。我们还发现，来自较温暖家庭气候的人群暗呼吸率，光补偿点和WUE较低。随着Johnsongrass遍及美国的发展，非生物和生物环境正在推动其遗传学，表型及其潜在生理学的变化。我们的研究表明，评估入侵植物的生理性状非常重要，尤其是与家庭气候有关的生理性状。