Sistema distílico e biologia reprodutiva de cinco espécies de Psychotria L. (Rubiaceae) em dois fragmentos do sudeste Goiano
Carregando...
Data
2013-09-18
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
Distyly is a reproductive strategy to promote cross-pollination
and difficult self-pollination, characterized by the presence of two floral morphs, the pin and the
thrum morph. The study aimed to describe the phenological behavior and investigate aspects
related to the distylous system of five Psychotria species, such as the pollination biology, the
floral morphology, the isoplety and the incompatibility system of the species. The studies were
performed in the "Parque Municipal da Mata do Setor Santa Cruz" and "in the Pasto do
Pedrinho", in the municipality of Catalão, Goiás. The five species of the genus Psychotria were:
P. hoffmannseggiana, P. capitata, P. prunifolia, P. deflexa. and P. trichophoroides. The flowers
were collected and fixed in 70% ethanol for the morphometric analysis. The phenology was held
for one year for each species. The incompatibility system was tested using hand pollination. The
flower visitors were collected, labeled and identified. The results indicate that P.
hoffmannseggiana, P. capitata, P. deflexa and P. trichophoroides present distyly, only P.
prunifolia was considered as pin-monomorphic . In the reproductive system, P. prunifolia was
considered as self-compatible. Although, P. hoffmannseggiana, P. capitata, P. deflexa and P.
trichophoroides presented a self-incompatibility system. Regarding to the morphs ratio , all the
distylous populations were isopletic. The floral visitors of the five species confirm the
entomophilous pollination syndrome. In the phenology, the flower buds of the populations began
to emerge in September, one month before the beginning of the flowering, with the months of
highest incidence parallel to the emission of the flowers (October to December). The analysis of
the relationship between the corolla and the height of the intramorph reproductive verticils,
reveals that the corolla considerably interfered in the length of the floral organs. In the
reciprocity analysis, the influence of the corolla on the reciprocal herkogamy, had a null or
parcial effect in the reciprocity. The present study has been carried out with only one population
per species, and it would not be possible to assign distyly with the self-incompatibility of P.
capitata, P. deflexa, P. trichophoroides and P. hoffmannseggiana, or even with the
monomorphism and self-compatibility of P. prunifolia, as a general condition for these species.
However, the results of the present study and additional information from other populations of
these same species, lead us to believe that this scenario may repeat in other regions of Brazil.
Descrição
Palavras-chave
Citação
SÁ, Túlio Freitas Filgueira de. Sistema distílico e biologia reprodutiva de cinco espécies de Psychotria L. (Rubiaceae) em dois fragmentos do sudeste Goiano. 2013. 50 f. Dissertação (Mestrado em Biodiversidade Vegetal) - Universidade Federal de Goiás, Goiânia, 2013.