Cytotaxonomical studies of South Indian Capparidaceae.

Abstract

Cytotaxonomical studies have been made in 18 species coming under 6 genera of South Indian Capparidaceae, of which first record of chromosome number has been made in Cleome tenella, C. felina, C. aspera, Cadaba triphylla, Capparis brevispina, C. diversifolia, C. rotundifolia and C. divaricata.The basic chromosome number ranges from n=9 to n=80. The graph drawn on the frequency distribution of basic chromosome numbers shows a polymodel curve indicating thereby the evolution of species in many directions.The basic chromosome number may be n=7, from which species with n=9, n=10, n=11 and n=13 might have arisen by aneuploidy. The basic numbers n=16, n=17 and n=18 are secondarily balanced tetraploids by means of euploidy and aneuploidy. The basic numbers n=20, n=21 and n=22 may be secondarily balanced higher polyploids. The basic numbers n=49 and n=80 may be secondarily balanced allopolyploids which might have been evolved by hybridization of any two species followed by polyploidization. Therefore, autopolyploidy as well as allopolyploidy might have played important role in the the origin and evolution of the species of South Indian Capparidaceae.