Realization of Paleopolyploidy through Cytogenetic and Phylogenetic Characterization of Ten Species of Senna Mill., Fabaceae-Caesalpinioideae

Taxonomically and phylogenetically Senna species complex is quite intriguing having several status and origin related issues. Keeping this view in mind and scope of cytological investigation 10 species of same genus viz. S. alata, S. alexandrina, S. italica, S. obtusifolia, S. occidentalis, S. polyphylla, S. siamea, S. sulfurea, S. surattensis and S. tora were analysed in cytological frame and comprehensive data/ information, is generated. The basic chromosomal analysis revealed regular meiotic behavior despite the occurrence of some irregularities. The regular occurrence of multivalents especially quadrivalents at diplotene as well as diakinesis stage and unavailability of individual having x=7 chromosome number possibly indicates paleopolyploid origin of worked out taxa. Individual anther basis pollen analysis provides some clues regarding on going evolutionary processes in the same genus. Considered cytological parameters based cluster analysis and their comparison with molecular marker based phylogenetic analysis of earlier workers revealed the efficacy of used parameters in phylogenetic characterization of Senna species complex.