Polyploidy affects the ecological and evolutionary success of plants through altering phenotypes and physiological traits, which could enable polyploids to respond more easily to environmental changes. Here, we used two plant taxa (Rhodohypoxis baurii var. baurii and R. baurii var. platypetala; Hypoxidaceae) to compare leaf functional traits between diploid and polyploid individuals. We also tested if polyploid individuals increased water use efficiency under progressive soil water deficiency. Our findings show that polyploid individuals comprise larger, and more, stomata, have a higher maximum stomatal conductance and higher trichome density relative to diploids, yet water use efficiency did not differ between ploidies under well-watered and water deficit conditions. While stomatal-related traits and trichome density differed between the taxa, non-stomatal functional traits (e.g., leaf surface reflectance) did not differ, which might explain the similar WUE response to water treatment. Our research contributes to a growing body of work that suggests that physiological responses to changes in soil moisture and divergence in leaf functional traits due to polyploidy are likely to be species-specific.

多倍体通过改变表型和生理特性影响植物在生态和进化上的成功，这可能使多倍体对环境变化的反应更加容易。在这里，我们使用了两种植物种类（Rhodohypoxis baurii变种baurii和R. baurii变种阔瓣; Hypoxidaceae）比较二倍体和多倍体个体的叶片功能性状。我们还测试了多倍体个体是否在进行性土壤缺水的情况下提高了用水效率。我们的发现表明，与二倍体相比，多倍体个体具有更大，更多的气孔，具有更高的最大气孔导度和较高的毛状体密度，但在水源充足和缺水的条件下，倍性个体的水分利用效率没有差异。虽然各类之间的气孔相关性状和毛状体密度不同，但非气孔功能性状（例如，叶表面反射率）没有差异，这可能解释了对水处理的类似WUE响应。