Some epiphytes are adapted to extreme environments with the ability to survive drought as a result of their morphological (xeromorphism), anatomical (foliar trichomes or scales) and physiological features. In contrast to vegetative features, they may have diverse sexual reproductive strategies. Here we compared the flowering morphology, floral biology, breeding system and pollinators of Tillandsia duratii, T. loliacea and T. recurvifolia (Bromeliaceae) adapted to an extreme environment, the Brazilian Chaco. Tillandsia duratii and T. recurvifolia flower for 5–6 months, whereas T. loliaceae flowers for 11 months, mainly in the dry season, with low to high flowering overlap between them. Although these species generally show similar flowering morphology, they differ in size, colour, odour and/or floral functionality, suggesting non-sharing of pollinators among them. Bimodal pollination occurs in T. duratii (bees, moths other than hawkmoths) and T. recurvifolia (butterflies, hummingbirds); in T. loliacea, we recorded no floral visitors. Tillandsia recurvifolia is self-incompatible, has flowers which approach herkogamy and protandry, and depends on pollen vectors for fruit set. The other two species show reverse herkogamy, autonomous self-pollination and self-compatibility (mixed breeding system); therefore, pollinators are not required. The disparity in reproductive strategies among the three species suggests the possibility of selection for diverse modes of reproduction.

中文翻译：

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极端附生铁兰种（凤梨科）的适应性反应在巴西Chaco中通过不同的有性繁殖策略得到证明。

一些附生植物由于其形态（干性），解剖学（叶毛或鳞片）和生理特征而具有适应干旱的能力。与植物特征相反，它们可能具有多种性生殖策略。在这里，我们比较了开花的形态，开花生物学，繁育系统和传粉铁兰duratii，T. loliacea和T. recurvifolia（凤梨），适用于极端环境下，巴西查科。凤梨duratii和T. recurvifolia 5-6个月开花，而T. loliaceae花11个月，主要在干燥季节，它们之间的开花重叠程度从低到高。尽管这些物种通常表现出相似的开花形态，但它们的大小，颜色，气味和/或花的功能不同，表明它们之间没有授粉媒介。双峰授粉发生在T. duratii（蜜蜂，比其他天蛾蛾）和T. recurvifolia（蝴蝶，蜂鸟）; 在T. loliacea中，我们没有记录到花卉访客。铁线兰是自交不亲和的，有接近雌雄同株和protandry的花，并且取决于花粉载体的坐果。其他两个物种表现出逆向同源性，自主自花授粉和自交配（混合育种系统）。因此，不需要传粉者。这三个物种之间在繁殖策略上的差异表明选择不同繁殖方式的可能性。