Abstract：
Gametophytic self-incompatibility (GSI) has been mainly described in species-rich clades within Orchidaceae. We report GSI for a genus within Maxillariinae, one of the most conspicuous and diverse subtribes of neotropical orchids. Here, we describe the reproductive system of Brasiliorchis picta, B. phoenicanthera, and B. porphyrostele. Anatomical studies of fruit development showed that pollen tubes of aborted, self-pollinated flowers degenerate half-way in the stylar channel and never reach the ovules. Spontaneous self-pollination and emasculation set no fruits for none of the sampled species, thus supporting the hypothesis that these three species studied rely on the agency of pollinators and pollinator-mediated cross-pollination to set fruit. Fruit set from cross-pollinations ranged from 33.4 to 77.5%. One self-pollinated fruit of B. porphyrostele developed to completion. All other fruits aborted between 10 and 21 days after pollination. These data support previous evidence of variable strength GSI being exhibited in orchid species. Additional studies of self-incompatibility systems are needed to evaluate their role in species diversification and evolution of reproductive strategies in Maxillariinae and to allow for effective conservation strategies of threatened orchid species.
摘要：
配子体自交不亲和（GSI）主要在兰科中物种丰富的进化枝中进行了描述。我们报告了Maxillariinae属的GSI，新热带兰花最显眼和最多样化的亚部落之一。这里,我们描述了巴西兰花的生殖系统，B.phoenicanthera，和B.卟啉。果实发育的解剖学研究表明，花粉管流产，自花授粉的花朵在花柱通道中退化一半，永远不会到达胚珠。自发的自花授粉和去雄对没有一个采样物种没有收获，因此支持以下假设：所研究的这三个物种依靠传粉者和传粉者介导的异花授粉来结果。异花授粉的坐果率为33.4％至77.5％。卟啉的一个自花授粉果实发育完成。所有其他果实在授粉后10至21天之间流产。这些数据支持先前在兰花物种中表现出可变强度GSI的证据。需要对自我不相容性系统进行其他研究，以评估其在Maxillariinae物种多样化和生殖策略进化中的作用，并考虑到受威胁的兰花物种的有效保护策略。
