In Bromelioideae, the so-called nidularioid complex contains closely related genera, the circumscription of which has been problematic. The goal of this study was to describe the ovary and ovule anatomy of six species of the nidularioid complex belonging to Canistropsis, Canistrum, Edmundoa, Neoregelia, Nidularium and Wittrockia and to use these characters in a parsimony analysis of relationships. In all analysed species, schizogenous-type aerenchyma is present in the ovarian mesophyll. Edmundoa lindenii has trichomes on the ovary surface, and this character appears to be an autapomorphy for the species. Canistrum aurantiacum exhibited some autapomorphies, such as four cell layers in the outer integument, non-elongated cells in the nucellar epidermis and three or four layers of cells in the parietal tissue. In the remaining species of the complex, the presence of transversally orientated ovules and anticlinally elongated cells in the outer integument in the micropylar region appear to be synapomorphies. Canistrum aurantiacum shares few characters with the other species; these results and the latest phylogenetic analysis show that Canistrum spp. do not belong to the current nidularioid clade.
Tillandsioideae are composed of nine genera, most of these with unclear delimitation. The morphoanatomy of ovules and ovaries of 83 species from seven different genera was studied under light or scanning electron microscopy to contribute to the understanding of the relationships in the group. The nucellar epidermis and the parietal tissue showed a regular pattern for all Tillandsioideae. The presence of chalazal appendages, however, and their shape and size varied between the genera analysed. Most species had a single acuminate chalazal appendage. Catopsis was the only genus with multiple appendages. Guzmania and Racinaea lacked this structure. The integuments also presented a variable length and thickness among the different genera. The four to six layers of the outer integument were unique in Catopsis and the three cell layers condition in the inner integument of Tillandsia should be a retained feature as it was also observed in Catopsis. Many characteristics in ovule morphology presented here have great systematic value for distinguishing genera of the Tillandsioideae. In addition, these features can also help in the understanding of ovule evolution in Bromeliaceae as a whole.
A família Arecaceae, reconhecida mundialmente pela sua importância econômica e ambiental, está em franco declínio populacional devido, principalmente, a ação antropogênica. Este trabalho consiste em uma revisão ampla das publicações científicas sobre a Família e, mais especificamente, dos gêneros Butia (Becc.) Becc. e Syagrus Mart. Aqui reunimos, organizamos e compilamos características botânicas e aspectos biogeográficos dos gêneros mencionados, com o objetivo de fundamentar trabalhos de pesquisa sobre alternativas viáveis à conservação dessas palmeiras e o atendimento das demandas de mercado por mudas dessas espécies tropicais. Uma alternativa proposta é o desenvolvimento de metodologias de hibridização entre esses dois gêneros, a fim de se obter respostas desejáveis para a finalidade comercial e, ao mesmo tempo, implementar planos de preservação para as populações de palmeiras nativas. Os dados levantados foram obtidos a partir de literatura científica em sites e revistas, no período de junho de 2019 a março de 2021. As buscas envolveram obras de 1970 a 2021. Nesta pesquisa exploratória, é primordial enfatizar a importância da interpretação e das opiniões dos pesquisadores, de forma que seja possível integrá-los às obras, proporcionando uma fundamentação teórica que dê sustentação a uma discussão a respeito do tema proposto.
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