A Case of Male Sterility in the Endangered Endemic Species Pitcairnia encholirioides L.B.Sm. (Bromeliaceae) of Brazilian Atlantic Forest Inselbergs

Premise of research. The endangered Pitcairnia encholirioides has limited flowering, a low rate of seed germination, and dominant asexual reproduction. These limitations suggest restrictions in sexual reproduction that could be caused by structural changes during development. Previous results indicated normal development of ovules and female gametophytes. Therefore, to test this hypothesis, anther wall development as well as microsporogenesis and microgametogenesis were analyzed.Methodology. Using cytogenetic and anatomical analysis, the study was undertaken to determine any cellular changes that might affect sexual reproduction of the species. Accordingly, we looked for (1) the presence of cytological changes during the development of anthers and pollen grains and/or (2) any cytogenetic aberration associated with meiosis of the sporogenous cells.Pivotal results. In the samples studied, anther wall development followed the monocotyledonous type, with late proliferation of the middle layer and secretory ta...