Although plant demography, genetics and reproduction are inter-related processes, few studies on rare tropical plants have attempted to integrate them. We used an integrated approach to study two endangered Neoregelia spp. from the Brazilian Atlantic Forest. The floral phenotypes of N. ibitipocensis and N. oligantha are similar, and both species are visited and pollinated only by bumblebees. Flowers of N. ibitipocensis secrete copious nectar, which bees can access only by forcing the corolla to open, whereas flowers of N. oligantha are nectarless. Neoregelia ibitipocensis is self-incompatible and pollen-limited, whereas N. oligantha is self-compatible and sets fruits spontaneously. Population growth rates indicate an increasing population size for both species, although to a lesser extent for N. oligantha. Genetic diversity as a whole was moderate; Bayesian analysis indicated a spatially structured cluster for N. ibitipocensis populations, and genetic diversity was scattered across the distribution of N. oligantha. Despite these differences, vegetative reproduction via clonal growth was the main component of population structuring in both species. Limited seed production in N. ibitipocensis and the risk of genetic drift in N. oligantha seem to be the main threats to their persistence.

中文翻译：

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两种稀有和濒临灭绝的新水牛科（凤梨科）的人口统计，遗传变异和生殖生物学

尽管植物人口统计学，遗传学和繁殖是相互关联的过程，但很少有关于稀有热带植物的研究尝试将其整合。我们使用一种综合方法来研究两个濒临灭绝的新球藻属。来自巴西大西洋森林。ibitipocensis和N. oligantha的花卉表型相似，并且两个物种仅由大黄蜂来访和授粉。ibitipocensis的花分泌丰富的花蜜，蜜蜂只能通过迫使花冠打开才能进入，而oligantha的花则是无花蜜的。irebitococensis是不相容的且受花粉限制，而寡头猪笼草具有自我适应能力，能够自发结出果实。人口增长率表明这两个物种的种群数量都在增加，尽管寡头猪笼草的数量却较少。总体而言，遗传多样性中等。贝叶斯分析表明对于在空间上构造簇N. ibitipocensis种群，和遗传多样性散落的分布N. oligantha。尽管存在这些差异，但通过克隆生长进行的营养繁殖仍是两个物种种群结构的主要组成部分。ibitipocensis的种子产量有限，而oligantha的遗传漂移风险似乎是对其持久性的主要威胁。