RESUMO -(Morfologia de sementes e do desenvolvimento pós-seminal de espécies de Bromeliaceae). O estudo teve como objetivos caracterizar as sementes, fornecendo informações sobre o tipo e o tempo médio de germinação e de formação de plântulas, além de descrever a morfologia do desenvolvimento pós-seminal de seis espécies de Bromeliaceae. Os resultados mostram germinação do tipo epígea e plântulas criptocotiledonares para todas as espécies. As porcentagens máximas de germinação obtidas, acima de 80%, indicam alta qualidade fisiológica das sementes. O tempo médio de germinação e de formação de plântulas foi de 4-15 e 8-18 dias, respectivamente. As sementes são filiformes a elípticas, lisas ou com apêndices plumosos. Os caracteres morfológicos mais relevantes para a diferenciação entre gêneros e subfamílias de Bromeliaceae referem-se à forma e ao tipo de apêndices das sementes, e na forma e tamanho da bainha cotiledonar, hipocótilo e raiz primária das plântulas, subsidiando estudos taxonômicos, ecológicos e na área de tecnologia de sementes. Palavras-chave:Bromelioideae, germinação, morfologia, Pitcairnioideae, Tillandsioideae ABSTRACT -(Seed and post-seminal development morphology on Bromeliaceae species). The aim of this study was to characterize the seeds, providing information about germination type and seedling rate, in addition to describe the post-seminal development morphology of the six species of Bromeliaceae. The results showed that the germination is epigeal with cryptocotylar seedlings. Maximum germination percentage was over 80%, for all species, indicating high physiological quality of the seeds. Germination and seedling rate was 4-15 and 8-18 days, respectively. Seeds are filiform to elliptical, smooth or with flight apparatus. The most relevant morphological characters for distinguishing among genera and subfamilies are shape and appendices of the seeds, form and size of the cotyledonal sheath, hypocotyl and primary root, providing information on taxonomic, ecological and seed technology studies.
RESUMO -O presente trabalho teve como objetivos definir o tipo de substrato e a temperatura mais adequados à germinação de sementes de jenipapo (Genipa americana L.), conhecer a morfologia das sementes e seu desenvolvimento pós-seminal, caracterizando as plântulas normais, o tipo de germinação e os padrões de anormalidade. Para tanto, realizou-se um experimento colocando-se as sementes sobre os seguintes substratos: papel, vermiculita e solo, nas temperaturas constantes de 20°C, 25°C, 30°C, e 35°C e alternada de 20°C-30°C. O delineamento estatístico empregado foi o inteiramente casualizado (5 x 3), com quatro repetições de 50 sementes. Foram analisados os parâmetros germinação normal (%) e velocidade de germinação. Os melhores resultados foram obtidos nas temperaturas constantes de 25°C, 30°C e 35°C, e nos substratos vermiculita e solo.Termos para indexação: plântula, Genipa americana. TEMPERATURE, SUBSTRATE AND POST-SEMINAL DEVELOPMENTABSTRACT -This study aimed to define the best substrate and temperature for germination of genipap (Genipa americana L. -Rubiaceae) seeds, and to describe the morphology of its seeds, postseminal development, normal and abnormal seedlings. The experiment was designed according to a 5 x 3 factorial with constant temperatures of 20°C, 25°C, 30°C and 35°C and alternated 20°C-30°C in filter paper, vermiculite and soil substrates. The following parameters were analyzed: normal percentage germination and speed of germination. The 25°C, 30°C and 35°C temperatures and vermiculite and soil substrates were the best conditions for seed germination.
Epiphytes are hyper‐diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non‐vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer‐reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non‐vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non‐vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events.
The morphology of Genipa americana seeds and post-seminal development was studied, and its germination response investigated in relation to storage in water, substrate water volume, osmotic potential and temperature and light regimes. The seeds are flattened and seedlings are phaneroepigeal with leafy cotyledons. Seeds stored in water kept viable for up to 6 mo, but germination and seedling emergence were reduced after 4 mo. Germination was not affected under water-logged conditions, but seedling emergence was reduced at the water volume corresponding to a water column two times deeper than the seeds' mean thickness (70 ml). When seeds were osmotically stressed, a reduction in the rate and germination percentage occurred at −0.2 MPa and germination was drastically inhibited at −0.6 MPa. Seeds germinated in a wide range of temperatures (15–40 °C), with optimum at continuous temperatures of 25 and 30 °C. Light was not required for germination, and no dormancy mechanisms were observed. The seed and seedling morphology and the germinative responses of the species may permit its regeneration in periodically flooded lowland forests and riparian habitats and are probably key factors in explaining the species' wide distribution.
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