Intraspecific and interspecific polyploidy of Brazilian species of the genus Inga (Leguminosae: Mimosoideae).
We investigated the karyotypes of 13 species of six sections of the genus Inga (Leguminosae-Mimosoideae) from Brazil. We used conventional Giemsa staining to identify numerical chromosomal variations and looked for karyotypic evolutionary patterns. The karyotypes generally had small chromosomes, varying from metacentric to submetacentric, with a basic number x=13. Nine of the species showed 2n=2x=26 (I. thibaudiana, I. cayennensis, I. ingoides, I. edulis, I. vera, I. subnuda, I. striata, I. bollandii, and Inga sp), while 2n=4x=52 was seen in a population of Inga cylindrical and of I. capitata, and in five populations of I. laurina. Additionally, 2n=8x=104 was observed in a population of I. cayennensis. Eight of these counts were new, while the counts of 2n=52 for I. laurina and 2n=26 for I. marginata, I. vera, I. subnuda, and I. edulis confirmed previous studies. We did not find cytological stability among the sections studied, with occurrence of significant intra- and inter-specific numerical variations. We conclude that polyploidy has played a significant role in karyotypic evolution in this group and that it occurred independently in several sections of the genus.
Departamento de Biologia, Universidade do Vale do Acaraú, Sobral, CE, Brasil.
M F
MF
Figueiredo
Laboratório de Citogenética Vegetal, Departamento de Biologia, Universidade Federal da Paraíba, Campus II, Areia, PB, Brasil.
R L A
RL
Bruno
Laboratório de Citogenética Vegetal, Departamento de Biologia, Universidade Federal da Paraíba, Campus II, Areia, PB, Brasil.
A E
AE
Barros e Silva
Laboratório de Citogenética Vegetal, Departamento de Biologia, Universidade Federal da Paraíba, Campus II, Areia, PB, Brasil.
S
S
Nascimento
Laboratório de Citogenética Vegetal, Departamento de Biologia, Universidade Federal da Paraíba, Campus II, Areia, PB, Brasil.
I G
IG
Oliveira
Laboratório de Citogenética Vegetal, Departamento de Biologia, Universidade Federal da Paraíba, Campus II, Areia, PB, Brasil lpfelix@cca.ufpb.br.
L P
LP
Felix
D005075:Biological Evolution; D001938:Brazil; D032461:Chromosomes, Plant / Q000235:genetics*; D007887:Fabaceae / Q000166:cytology* / Q000235:genetics; D059785:Karyotype; D011123:Polyploidy; D013045:Species Specificity