Data from: Effects of soil resources on expression of a sexual conflict over timing of stigma receptivity in a mixed-mating plant

While environmental factors strongly influence plant growth and reproduction, less is known about environmental effects on sexual selection and sexual conflict. In this study on mixed-mating Collinsia heterophylla we investigated whether soil resource environment affected traits associated with sexual conflict. In C. heterophylla a sexual conflict over timing of stigma receptivity occurs. Early stigma receptivity benefits pollen parents by securing paternity while late stigma receptivity benefits female fitness in terms of increased seed production. We performed hand-pollinations combining recipients and donors grown either in high or low resource environments and asked whether these treatments influenced sexual conflict traits – recipient- and donor-based influence on timing of stigma receptivity – and conflict costs related to reduced early seed production. We also asked whether resource environment affected nine traits related to general fitness and mating system. Sexual conflict-associated traits – timing of stigma receptivity and seed production – were generally unaffected by resource environment. While no universal effect of resources was detected, we did observe donor-specific responses to environment, suggesting that environment can nonetheless contribute to variation in timing of stigma receptivity. Recipients grown under low resources showed pronounced differences among donors for number of seeds per capsule, indicating that recipients favour some donors over others under resource-low conditions. Moreover, high resources increased number of flowers but reduced pollen germination rate, while other traits were unaffected, indicating variation in the response to resource environment for fitness- and mating system-traits. Our results suggest that even though soil resource environment had a low impact on the sexual conflict traits and related costs in C. heterophylla, it generated variability in pollen donor-influence on this trait and in recipient sorting among donors. Thus, it is possible that both sexual conflict and sexual selection is affected by environmental factors not only in animals but also in plants.尽管环境因子对植物生长与繁殖具有显著影响，但学界对环境因子如何作用于性选择（sexual selection）与性冲突（sexual conflict）的认知仍相对不足。 本研究以混合交配型的异叶科林草（Collinsia heterophylla）为研究对象，探讨土壤资源环境是否会影响与性冲突相关的性状。 在异叶科林草中，存在围绕柱头可授性（stigma receptivity）时序的性冲突现象：柱头提前可授可通过巩固父本地位使花粉亲本（pollen parents）获益，而柱头延迟可授则可通过提升种子产量使雌适合度（female fitness）受益。 我们开展了人工授粉（hand-pollinations）实验，将在高、低资源环境下培育的授粉受体（recipient）与花粉供体（donor）进行组合，以此探究这些处理是否会影响性冲突相关性状——即授粉受体和花粉供体对柱头可授性时序的影响——以及与早期种子产量降低相关的冲突成本。 此外，我们还探究了资源环境是否会影响9种与广义适合度（general fitness）及交配系统（mating system）相关的性状。 与性冲突相关的性状（柱头可授性时序与种子产量）整体上并未受到资源环境的显著影响。 尽管未检测到资源的普遍效应，但我们确实观察到花粉供体对环境的特异性响应，这表明环境仍可对柱头可授性时序的变异产生贡献。 在低资源环境下培育的授粉受体，其每蒴果种子数量在不同花粉供体间存在显著差异，这表明在资源匮乏条件下，授粉母本对部分花粉供体存在偏好。 此外，高资源环境会增加花朵数量，但降低花粉萌发率（pollen germination rate），其余性状则未受显著影响，这说明适合度与交配系统相关性状对资源环境的响应存在变异。 我们的研究结果表明，尽管土壤资源环境对异叶科林草的性冲突相关性状及其相关成本影响较小，但它会导致花粉供体对柱头可授性时序的影响以及授粉母本对花粉供体的选择分选产生变异。由此可见，环境因子不仅会作用于动物的性冲突与性选择，在植物中同样可能产生此类影响。