Abstract
Four accessions of B. serrata, a threatened tree species of the Indian Thar desert, showed a gametic number of n = 22 in the form of either 22 bivalents or a combination of both bivalents and univalent, confirming the somatic chromosome number as 2n = 44. They were characterized by the presence of mixture of bivalents and univalents, however multivalent associations were completely lacking. The highest mean value (3.6) of univalents was found in B. serrata BSJO-26314-D, while the minimum number of univalents per cell (0.15) was recorded in B. serrata BSJO-26314-B. By and large, the univalents, wherever encountered, apparently behaved normally leading to equal distribution of chromosomes at anaphase I. Male meiosis in all the accessions showed that genetic diversity exists in the natural populations of B. serrata. A multidisciplinary approach for genome diagnostics with the use of various DNA-based marker systems might shed more light on existing intra-specific genetic variation in B. serrata.
