BACKGROUND AND AIMS Plant individuals within a population differ in their phenology and interactions with pollinators. However, it is still unknown how individual differences affect the reproductive success of plants that have functionally specialized pollination systems. Here, we evaluated whether plant individual specialization in phenology (temporal specialization) and in pollination (pollinator specialization) affect the reproductive success of the crepuscular-bee pollinated plant Trembleya laniflora (Melastomataceae). METHODS We quantified flowering activity (amplitude, duration, and overlap), plant-pollinator interactions (number of flowers visited by pollinators) and reproductive success (fruit set) of T. laniflora individuals from three distinct locations in rupestrian grasslands of southeastern Brazil. We estimated the degree of individual temporal specialization in flowering phenology and of individual specialization in plant-pollinator interactions, and tested their relationship with plant reproductive success. KEY RESULTS Trembleya laniflora presented overlapping flowering, a temporal generalization, and specialized pollinator interactions. Flowering overlap among individuals and populations was higher than expected by chance but did not affect the individual interactions with pollinators and nor their reproductive success. In contrast, a higher individual generalization in the interactions with pollinators was related to higher individual reproductive success. CONCLUSIONS Our findings suggest that individual generalization in plant-pollinator interaction reduce the potential costs of specialization at the species level, ensuring reproductive success. Altogether, our results highlight the complexity of specialization/generalization of plant-pollinator interactions at distinct levels of organization, from individuals to populations, to species.

中文翻译：

---

开花和授粉个体变异对黄昏蜂鸣授粉植物繁殖成功的影响

背景和目的 群体中的植物个体在物候学和与传粉媒介的相互作用方面不同。然而，个体差异如何影响具有功能性专门授粉系统的植物的繁殖成功仍然未知。在这里，我们评估了植物个体在物候学（时间专业化）和授粉（传粉媒介专业化）方面的专业化是否会影响黄昏蜜蜂授粉植物 Trembleya laniflora（Melastomataceae）的繁殖成功。方法我们量化了巴西东南部 rupestrian 草原三个不同位置的 T. laniflora 个体的开花活动（振幅、持续时间和重叠）、植物-传粉媒介相互作用（传粉媒介访问的花朵数量）和繁殖成功率（结果）。我们估计了开花物候的个体时间专业化程度和植物 - 传粉者相互作用的个体专业化程度，并测试了它们与植物繁殖成功的关系。主要结果 Trembleya laniflora 呈现重叠开花、时间概括和专门的传粉媒介相互作用。个体和种群之间的开花重叠偶然高于预期，但不影响个体与传粉媒介的相互作用，也不影响它们的繁殖成功。相比之下，与传粉媒介相互作用的个体泛化程度越高，个体繁殖成功率越高。结论 我们的研究结果表明，植物-传粉媒介相互作用中的个体泛化降低了物种水平专业化的潜在成本，确保繁殖成功。总而言之，我们的结果突出了从个体到种群再到物种的不同组织级别上植物 - 传粉媒介相互作用的专业化/泛化的复杂性。