Tillandsia is the bromeliad genus containing the largest number of species, with wide geographic dispersion and an important ecological role in the ecosystems. Investigations of pollen morphology are important to support taxonomic and conservation studies as well as to choose promising species for cross‐pollination to obtain hybrids. The objective of this study was to evaluate the morphology, production, and viability of pollen grains of 24 Tillandsia species that naturally occur in the state of Bahia, Brazil. Pollen grains were acetolized and analyzed by scanning electron microscopy. The pollen were germinated in vitro in two culture media (BM and BKM) and collected at three floral development stages (pre‐anthesis, anthesis and post‐anthesis). Pollen viability also was analyzed by staining with Alexander's solution and acetocarmine in three floral development stages. Variations in the ornamentation and size of the pollen were observed among the species studied, with the majority having medium size, while T. polystachia and T. juncea had large grains and the subgenera Diaphoranthema and Phytarrhiza had small grains. The pollen of the majority of species had bilateral symmetry, with a single irregularly shaped colpus, semitectate exine and reticulated‐heterobrochate surface. The pollen presented high germination percentage, tube length and viability according to the histochemistry, except for T. recurvata, T. usneoides and T. loliacea. The BKM medium and collection of pollen during anthesis produced the best results for the Tillandsia species. The results can support studies of the taxonomy and conservation of these species, which have great environmental importance and high value for ornamental purposes.

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Species of Tillandsia L. are widely distributed in Brazilian ecosystems, and in the state of Bahia they can be found in the Atlantic Forest, Caatinga and Cerrado biomes. Studying the reproductive aspects of these species can support their management and conservation. In particular, stigma morphology is a conserved trait of Bromeliaceae and stigma receptivity can influence the success of pollination. The objective of this study was to characterize the morphoanatomy and classify the stigma types of Tillandsia species by means of light and scanning electron microscopy, as well as to evaluate the stigma receptivity by different methods and at three floral development stages. A total of 21 Tillandsia species found in Bahia were evaluated. The stigma receptivity was assessed with hydrogen peroxide (3%) and a solution of α‐naphthyl acetate. Four stigma types were observed: conduplicate‐spiral for the species of the Tillandsia subgen. Tillandsia, simple‐erect for species of T. subgen. Diaphoranthema, and simple‐truncate for the species of T. subgen. Phytarrhiza. The species of the T. subgen. Anoplophytum had three morphological types, conduplicate‐spiral, conduplicate‐patent and simple‐erect. All the species had trifid stigmas, monostratified epidermis, numerous idioblasts containing raphides in the fundamental parenchyma and an individual vascular bundle for each carpel. In all the species studied by the two methods of stigma receptivity the highest enzyme activity was observed during anthesis. The morphoanatomy of the stigma and style provides important information for the taxonomy of Tillandsia and the data on stigma receptivity can support studies of the reproduction and conservation of these species.

Tillandsia L. is the largest genus of the family Bromeliaceae, containing 755 species and seven subgenera. Morphoanatomical studies of leaves provide useful characteristics to phylogenetic, taxonomic, and ecological analyses. This study aims to characterize and compare the leaves of 24 species of the four subgenera of Tillandsia that occur in Bahia and also perform adaptative inferences to environmental responses.The results of the species' morphoanatomical studies were compared through dissimilarity analysis. The species have rosulate leaves with varying lengths and widths. The peltate trichomes present variation in the indument density and the length of their wing and central disk. The stomata are longitudinally distributed in one or both sides of the limb. The mesophyll is dorsiventral and presents aquiferous and chlorophyllic parenchymas. The vascular bundles are collateral and partially covered by fibers, except for Tillandsia linearis. Based on the dissimilarity analysis, it was possible to identify the formation of five groups. Group G1 was composed of T. linearis, which diverged from the other species of the subgenus. Group G2 was formed by the remaining species of the subgenus Phytarrhiza. G3 and G4 presented the species of the subgenus Diaphoranthema and Tillandsia, respectively. Group G5 gathered 11 species of the subgenus Anoplophytum and presented higher variability than the other subgenera. Based on the results, the morphoanatomical characteristics can be used to characterize and group Tillandsia species, besides confirming the morphological variability of these species to the epiphyte habit in different environments, especially xeric ones.

This study assessed and compared different methods for vegetative propagation of a miniature ornamental pineapple hybrid (ORN-MUT), seeking to determine the best method for production of plantlets, as well as for removal of the PMWaV viral complex from plants cultured in vitro, for production of healthy parent plants. Pineapple wilt is a disease that can cause large economic and is caused by a viral complex called Pineapple mealybug wilt-associated virus (PMWaV). For this, four propagation methods were evaluated (conventional, stem sectioning, micropropagation and etiolation of nodal segments). The time necessary for each method and the number of plants formed were assessed. Stem tips (0.5 mm) were cultured and indexed for three PMWaV types. Conventional propagation produced 17 plantlets per plant in 566 days, stem sectioning produced 2.3 plantlets per stem in 591 days, while the conventional micropropagation technique produced 1,284 plants after four subcultures in 778 days. Stems etiolated for 60 days showed peak production in the second subculture, with 1,224 plants. This method required 883 days to obtain plants with ideal size for transplantation to the field. In turn, stems etiolated for 120 days produced 935 plants at the end of four subcultures, with peak output in the third subculture, in which the plants could be cultivated in the field after 943 days. Conventional micropropagation and etiolation for 60 days were the best methods for production of plantlets of the ORN-MUT hybrid. The results of this work showed that the cultivation of shoot tips is an efficient strategy to remove the PMWaV complex and obtain healthy mother plants and can be a useful tool for other varieties of pineapple.