Karyological studies of thirty two varieties of black gram (Phaseolus mungo L.).

Abstract

Karyotypic analysis of thirty two varieties of Phaseolus mungo L. showed reasonable differences between the varieties on chromosome length, position of primary constriction and in TF%. Two pairs of chromosomes were secondarily constricted with subterminal primary constriction and occupy first and second positions in the somatic complement in almost all the varieties. In the rest of the chromosomes, the majority showed submedian primary constriction and few showed median constriction. An average karyotype of Phaseolus mungo L. has been suggested basing on the results included herewith and also considering the previous reports on this line.The observation of TF% ranging from 24.31 to 27.82 revealed a symmetrical karyotypes for nineteen varieties. The rest were observed to be asymmetrical with TF% ranging from 28 to 38.23. The importance of karyotypic differences in evolution of varieties within a species has been discussed.