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1.
An Acad Bras Cienc ; 93(4): e20191446, 2021.
Article in English | MEDLINE | ID: mdl-34705934

ABSTRACT

Floral traits associated with functional groups of pollinators have been largely employed to understand mechanisms of floral diversification. Hymenaea is a monophyletic legume genus widely recognized to being bat-pollinated, with nocturnal anthesis and copious nectar. The most of species has short-paniculate inflorescences, white and robust flowers, congruent with a bat-pollination syndrome. However, other Hymenaea species show a different floral pattern (e.g., long-paniculate inflorescences and smaller flowers) which we report here as being bird pollinated. We examined the floral traits and visitors of Hymenaea oblongifolia var. latifolia and identified evolutionary shifts in floral traits associated with potential pollinators of Hymenaea species. Floral traits of H. oblongifolia var. latifolia differ from those expected for bat-pollinated flowers in species of sect. Hymenaea, and we observed hummingbirds collecting nectar legitimately. Our phylogenetic analysis did not support the monophyly of the taxonomic sections and suggests that bat pollination is ancestral in Hymenaea, with bird pollination evolving later. The transition coupling with shifts in the timing of anthesis and other floral traits. Pollinator-mediated evolutionary divergence hypothesis partially explains the Hymenaea diversification in the Neotropics. It is congruent with those species shifting from traits linked traditionally to bat pollination to hummingbird pollination.


Subject(s)
Fabaceae , Hymenaea , Flowers , Phylogeny , Pollination , Syndrome
2.
An Acad Bras Cienc ; 91(1): e20180308, 2019.
Article in English | MEDLINE | ID: mdl-30569969

ABSTRACT

Our understanding of the impacts of ongoing global warming on terrestrial species has increased significantly during the last several years, but how climatic change has affected, and will affect, the distribution of earthworms remains largely unknown. We used climate niche modeling to model the current distribution of the giant earthworm Rhinodrilus alatus - an endemic species of the Cerrado Domain in Brazil, which is traditionally harvested and commercialized for fishing bait. R. alatus is sensitive to environmental changes because climate, in synergy with soil attributes, determine its annual reproductive cycle and distribution. The paleoclimatic reconstructions predict important geographical shifts from LGM (~21,000 yBp) to the present potential distribution of R. alatus: range expansion, fragmentation, and shrinkage of the current core area. Further, the 2070 scenarios predict substantial shrink and losses of stable areas. Our results indicate that climate change will not only affect the extent of the distribution, but will also promote significant fragmentation and a geographical shift to outside of the currently recognized geographical boundaries. In this context, populations of R. alatus would decline and traditional harvesting would collapse, requiring immediate implementation of management and conservation measures for the species and economically sustainable alternatives for the local community.


Subject(s)
Animal Distribution , Global Warming , Oligochaeta/physiology , Animals , Brazil , Forecasting , Geography , Oligochaeta/anatomy & histology , Population Dynamics/trends , Reference Values , Species Specificity
3.
Can J Microbiol ; 60(12): 847-56, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25403761

ABSTRACT

The fungal endophyte community associated with Baccharis trimera, a Brazilian medicinal plant, was characterized and screened for its ability to present antimicrobial activity. By using molecular methods, we identified and classified the endophytic fungi obtained into 25 different taxa from the phyla Ascomycota and Basidiomycota. The most abundant species were closely related to Diaporthe phaseolorum, Pestalotiopsis sp. 1, and Preussia pseudominima. The differences observed in endophytic assemblages from different B. trimera specimens might be associated with their crude extract activities. Plants that had higher α-biodiversity were also those that contributed more to the regional (γ) diversity. All fungal isolates were cultured and their crude extracts screened to examine the antimicrobial activities. Twenty-three extracts (12.8%) displayed antimicrobial activities against at least one target microorganism. Among these extracts, those obtained from Epicoccum sp., Pestalotiopsis sp. 1, Cochliobolus lunatus, and Nigrospora sp. presented the best minimum inhibitory concentration values. Our results show that the endophytic fungal community associated with the medicinal plant B. trimera included few dominant bioactive taxa, which may represent sources of compounds with antifungal activity. Additionally, the discovery of these bioactive fungi in association with B. trimera suggests that Brazilian plants used as folk medicine may shelter a rich fungal diversity as well as taxa able to produce bioactive metabolites with antimicrobial activities.


Subject(s)
Antifungal Agents/pharmacology , Ascomycota/physiology , Baccharis/microbiology , Basidiomycota/physiology , Endophytes/physiology , Fungi/drug effects , Grassland , Plants, Medicinal/microbiology , Ascomycota/classification , Ascomycota/isolation & purification , Basidiomycota/classification , Basidiomycota/isolation & purification , Biodiversity , Brazil , Endophytes/classification , Endophytes/isolation & purification , Microbial Sensitivity Tests
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