Data/hora: 04/06/2024 02:14:01

Biblioteca(s): | Embrapa Gado de Leite.
Data corrente: | 02/12/2014
Data da última atualização: | 05/02/2024
Autoria: | HMELJEVSKIA, K. V.; FREITAS, L.; DOMINGUES, R.; PEREIRA, A. R.; CANCIO, A. S.; ANDRADE, A. C. S.; MACHADO, M. A.; VICCINI, L. F.; FORZZA, R. C.
Afiliação: | KARINA V. HMELJEVSKIA, UFRJ; LEANDRO FREITAS, Jardim Botânico do Rio de Janeiro; ROBERT DOMINGUES, UFJF; ALBA REGINA PEREIRA, Centro Federal de Educaçãoo Tecnológica Celso Suckow da Fonseca; ALINE S. CANCIO, Jardim Botânico do Rio de Janeiro; ANTONIO CARLOS S. ANDRADE, Jardim Botânico do Rio de Janeiro; MARCO ANTONIO MACHADO, CNPGL; LYDERSON F. VICCINI, UFJF; RAFAELA C. FORZZA, Jardim Botânico do Rio de Janeiro.
Título: | Conservation assessment of an extremely restricted bromeliad highlights the need for population-based conservation on granitic inselbergs of the Brazilian Atlantic Forest.
Ano de publicação: | 2014
Fonte/Imprenta: | Flora, n. 209, n. 5/6, p. 250-259, 2014.
DOI: | https://doi.org/10.1016/j.flora.2014.03.004
Idioma: | Inglês
Conteúdo: | Inselbergs support highly specialized vegetation with many endemic species. Here we studied by an integrated approach a rare and threatened species from Brazilian inselbergs. Pitcairnia encholirioides (Bromeliaceae) is included in the Red Book of Brazilian Flora, in the ‘Endangered’ category. Only one single population on unprotected private property was known at the beginning of our study. We studied several life-history traits including clonal growth, reproductive biology, seed germination and cryopreservation, and genetic diversity. Pitcairnia encholirioides has the phalanx type of clonal growth strategy. Its self-incompatible flowers are successfully pollinated by hummingbirds. However, less than 5% of clonal fragments produced flowers. Seeds can be wind-dispersed, but most of them are dispersed by gravity and fall close to the mother plant. The percentage and speed of germination were significantly affected by different temperatures, water potential, and red:far-red light ratios, although more than 80% of seeds germinated under optimal physiological conditions. The genetic diversity was very low (Hsp = 0.09) and the population was highly structured (ΦST = 0.51). The combination of dispersal mode and environmental conditions seems to be the main factor leading to the rarity of P. encholiroides. Low genetic diversity combined with small population size and low reproductive capacity suggest that the species is highly susceptible to environmental disturbance. Similarly to P. encholiroides, many species from Brazilian inselbergs are restricted to only a few localities. For more widely distributed species, a higher genetic diversity among populations has been consistently detected. The pattern of low gene flow of many species with small distributions highlight the importance of population-based conservation strategies for such taxa the areas of occurrence of which being naturally fragmented at inselberg sites. We discuss some strategies that may help in conservation of such species.
Palavras-Chave: | Clonal plants; Endemism; Rarity.
Thesaurus Nal: | endangered species; ex situ conservation; in situ conservation.
Categoria do assunto: | F Plantas e Produtos de Origem Vegetal
Registro original: | Embrapa Gado de Leite (CNPGL)
Exemplares: | CNPGL - (21550-1) - UPC - AP - DD -  -  -  - DIS