CITOGENÉTICA EVOLUTIVA EN LEGUMINOSAS AMERICANAS

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

RODRIGUESIA

Jardim Botanico Rio de Janerio, Brasil

Lugar: Rio de Janeiro; Año: 2008 vol. 59 p. 423 - 433

0370-6583

In this work, the chromosomes features described so far on Americans legumes are presented. Through a simultaneous analyses of these data, plus morphological and molecular characters, hypothesis about chromosome changes during the family divergence and speciation processes are proposed. The chromosome studies showed a great inter-generic, inter and intra-specific variability, as well large differences in genome sizes between genus, species and populations. By postulating an ancestral basic number of seven (x=7), we deduce that the polyploid hybrid speciation was very important in the diversification of the family. Due to increasing and decreasing disploidy processes, secondary basic numbers and modified polyploids series could had been arise both at diploid and polyploid levels. On the other hand, recurrence origin of polyploids, occurrence of inter-genomic rearrangements, hybridization and secondary polyploidy are all processes that difficult the natural grouping of taxa in the Leguminosae family.