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A cytogenetic study of seven species of Centrosema (dc.) benth (Leguminosae - Papilionoideae)

Alice Battistin; Marina Guedes Vargas

Departamento de Biologia, Setor de Genética, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97119 Santa Maria, RS, Brasil

ABSTRACT

Mitotic metaphases and prophases were analyzed in seven Centrosema (DC.) Benth. species for chromosome number counts and observation of heteropycnotic regions. Variation in chromosome number was detected among the species. C. shotii and C. pascuorum have 2n = 22 chromosomes, while the remaining species have 2n = 18 chromosomes. C. pascuorum and C. virginianum were the most contrasting species, the former having only metacentric and submeta-centric chromosomes, while the latter has metacentric, submetacentric, acrocentric and telocentric chromosomes. Three species have a satellite pair and one species has only one satellite. In the other species, were not found satellites. The location of the heteropycnotic regions was proximal in all seven species.

Keywords: cytogenetic; species; Centrosema.

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