New chromosome reports in the subtribes Diocleinae and Glycininae (Phaseoleae:Papilionoideae: Leguminoseae)

ESPERT, S.; SEDE, S. M.; FORTUNATO, R. H.; POGGIO, L.

BOTANICAL JOURNAL OF THE LINNEAN SOCIETY

Linnean Society

Lugar: Londres; Año: 2008 vol. 158 p. 336 - 341

0024-4074

The base number x = 11 proposed for the tribe Phaseoleae is the most probable base number of all the subtribes included in Phaseoleae as well. Some aneuploid reductions are evident in Collaea and Galactia (Diocleinae) as well as chromosome duplications in Amphicarpaea, Cologania and Glycine (Glycininae). The aim of this study was to improve the cytological knowledge of some species of Galactia and Collaea (Diocleinae), to examine the anomalous counts reported for Calopogonium (Glycininae) and to corroborate its taxonomic position. Additionally, a molecular phylogeny was constructed using nuclear ribosomal DNA sequences (ITS) and the chromosome number was optimized on the topology. In this work the chromosome counts for Galactia lindenii, G. decumbens and Collaea cipoensis (2n = 20) and Calopogonium sericeum (2n = 22) are reported for the first time. The new reports for Galactia and Collaea species are in agreement with the chromosome number proposed for the subtribe Diocleinae. The present study rejects the idea of a cytologically anomalous Calopogonium and based on the phylogenetic analysis, the position of this genus within the subtribe Glycininae is corroborated. The ancestral basic chromosome number x = 11 proposed for Phaseolae is in agreement with the evolutionary pathway of the chromosome number analyzed in this work.