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1.
Plants (Basel) ; 13(12)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38931086

RESUMO

Discussing homology relationships among secretory structures remains a relatively underexplored area in botanical research. These structures are widely dispersed within Malpighiales, one of the largest orders of eudicots. Within Malpighiales, both extranuptial and nuptial nectaries are present, and they do not seem homoplastic or share evolutionary connections. Particularly in Malpighiaceae, extensive research has focused on the ecological interactions mediated by glands. Botanists largely agree that elaiophores in sepals of Neotropical Malpighiaceae have evolved from extrafloral nectaries on leaves. However, the evolutionary origin of elaiophores has yet to be thoroughly examined, particularly in comparison to outgroups. This study provides empirical evidence on the ontogeny of elaiophores and investigates their evolutionary origins and homology relationships across different lineages of Malpighiales using comparative anatomy. Our findings suggest that elaiophores are likely homologous to extranuptial nectaries found in sepals of other Malpighiales lineages, originating from nectaries on leaves. This discussion is a starting point for future studies exploring the evolution of nectaries found in flowers, whether extranuptial or nuptial, and their potential origins from nectaries in vegetative organs such as leaves. Understanding these relationships could shed light on the selective pressures influencing floral morphologies.

2.
Biota neotrop. (Online, Ed. port.) ; 12(2): 49-56, Apr.-June 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-645384

RESUMO

Although Miconia mirabilis is a very common species in disturbed forest areas and is known for providing food resources for the local fauna, little is known about its reproductive phenology and other ecological aspects. The present study compares intra- and inter-annual patterns in the reproductive phenophases of that species in three distinct physiognomies of Atlantic Forest in Southeastern Bahia based on semi-quantitative observations conducted over a period of three years. We searched for possiblerelationships with climatic variables, differences among sites and synchrony. Both the flowering and fruiting strategies of M. mirabilis were classified as annual extended in all three study sites. We found no significant differences among years. Despite low seasonality of the regional climate, intensities of the different phenophases were negatively correlated with day length and temperature. In general, inter- and intra-population synchrony for flowering and fruiting was high (between 0.65 and 0.78), except for inundated forest, probably due to the stress caused by flooding. Given that Miconia mirabilis has the potential to be an important food resource for the local fauna due to the large quantities of flowers and fruits produced and their almost year-round availability, and its capacity for occupying impoverished areas, the species may be considered in restoration programs as a potentially interesting species capable of attracting frugivores to disturbed areas.


Apesar de Miconia mirabilis ser uma espécie comum em áreas de floresta perturbada e conhecida por fornecer recursos alimentares para a fauna local, pouco se sabe sobre sua fenologia reprodutiva e outros aspectos ecológicos. O presente estudo teve como objetivo comparar os padrões intra e interanual das fenofases reprodutivas da espécie em três fisionomias distintas de Floresta Atlântica no sudeste da Bahia com base em observações semi-quantitativas, realizadas num período de três anos. Também procurou por possíveis relações com as variáveis climáticas, diferenças entre os locais e sincronia. Ambas as estratégias, floração e frutificação, de M. mirabilis foram classificadas como anuais estendidas em todos os três locais de estudo. Não houve diferenças significativas entre os anos. Apesar do clima regional apresentar baixa sazonalidade, as intensidades das diferentes fenofases foram negativamente correlacionadas com o comprimento do dia e temperatura. Em geral, a sincronia inter e intra populacional para a floração e frutificação foi alta (entre 0,65 e 0,78), exceto para a floresta inundada, provavelmente devido ao estresse causado pelo solo alagado. Assim, Miconia mirabilis tem potencial de ser um importante recurso alimentar para a fauna local, devido a grande quantidade de flores e frutos produzidos, sua disponibilidade quase o ano todo, e por ocupar áreas empobrecidas, a espécie pode ser considerada potencialmente interessante em programas de restauração e capaz de atrair animais frugívoros em áreas perturbadas.

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