Meiotic Studies in Withania somnifera (L.) Dunal.: A Threatened Medicinal Herb of Indian Thar Desert

Withania somnifera recently categorized as threatened plant of Rajasthan and known for its high medicinal value has been studied for existing genetic variations in four accessions collected from four different locations. From the present studies it is apparent that the gametic number of W. somnifera is n = 24 and 2n = 48. From the combined information generated by present author and earlier workers, it is tentatively believed that W. somnifera might be of allopolyploid origin with basic number of x = 12. In this case also precocious separation of rod bivalents but not structural hetrozygosity might be the reason for occurrence of univalents. From the detailed meiotic analysis, it is concluded that the species diversification is brought out by polyploidy in W. somnifera. Multidisciplinary approach for genome diagnostics with use of various marker systems might through more light on existing intra-specific genetic variation in W. somnifera.