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 .
B. A. Mir, S. Loul, A. Kumar, M. K. Kaul, A. S. Soodan and S. N. Raina, “Intraspecific Variation in the Internal Transcribed Spacer (ITS) Regions of rDNA in Withania somnifera (Linn.) Dunal,” Indian Journal of Biotechnolog, Vol. 9, 2010, pp. 325-328.
A. Kumar, B. A. Mir, D. Sehgal, T. H. Dar, S. Koul, M. K. Kaul, S. N. Raina and G. N. Qazi, “Utility of a Multidisciplinary Approach for Genome Diagnostics of Cultivated and Wild Germplasm Resources of Medicinal Withania somnifera, and the Status of New Species, W. ashwagandha, in the Cultivated Taxon,” Plant Systematics and Evolution, Vol. 291, No. 3-4, 2011, pp. 141-151. doi:10.1007/s00606-010-0372-4
M. M. Bhandari, “Flora of the Indian Desert,” Scientific Publishers, Jodhpur, 1990.
A. Chevallier, “The Encyclopedia of Medicinal Plants,” Dorling Kindersley, London, 1996.
G. S. Chatha and S. S. Bir, “Cytological Evolution in Woody Taxa of Gamopetalae and Monochlamydae from South India,” Plant Sciences, Vol. 9, 1998, pp. 199-256.
V. Singh and R. P. Pandey, “Ethnobotany of Rajasthan,” Scientific Publishers, Jodhpur, 1998.
W. Emboden, “Narcotic Plants,” Studio Vista, London, 1979.
C. K. Atal, “Schwarting AE. Ashwagandha––An Ancient Indian Drug,” Economic Botany, Vol. 15, No. 3, 1961, pp. 256-263. doi:10.1007/BF02862166
C. K. Atal and A. E. Schwarting, “Schwarting. Intraspecific Variability in Withania somnifera. I. A Preliminary Survey,” Llyodia, Vol. 25, 1962, pp. 78-87
N. S. Dhalla, K. C. Gupta, N. S. Sastry and C. L. Malhotra, “Comparative Studies on Withania somnifera Dunnl. and Withania ashwagandha Kaul,” Indian Journal of Pharmacology, Vol. 23, 1961, pp. 126-127.
K. N. Kaul, “The Origin, Distribution and Cultivation of Ashwagandha the so Called Withania somnifera of Indian Literature,” Symposium on the Utilization of Indian Medicinal Plants, Council of Scientific & Industrial Research, New Delhi, 1957, pp. 7-8.
S. Negi, A. Singh and M. Lakshmikumaran, “Genetic Variation and Relationship among and within Withania species as Revealed by AFLP Markers,” Genome, Vol. 43, No. 6, 2000, pp. 975-980.
H. Y. MohanRam and I. Kamini, “Embryology and Fruit Development in Withania somnifera Dunal.,” Phytomorphology, Vol. 14, No. 3, 1964, pp. 574-587.
S. R. Baquar, S. Akhtar and A. Hussain, “Meiotic Chromosome Numbers in Some Vascular Plants of Indus Delta I,” Botaniska Notiser, Vol. 118, 1965, pp. 289-298.
P. N. Bhaduri, “Chromosome Numbers of Some Solanaceous Plants of Bengal,” Journal of the Indian Botanical Society, Vol. 12, 1933, pp. 56-64.
J. Miege, “Troisieme Liste de Numbers Chromosomiques d’Especes d’Afrique Occidentale,” Ann Fac Sci Univ Dakar., Vol. 5, 1960, pp. 75-85.
S. S. Bir and M. Sidhu, “Cytological Observations on Weed Flora of Patiala District, Punjab,” In: S. S. Bir, Eds., Recent Researches in Plant Sciences, Kalyani Publishers, Ludhiana, 1980, pp. 261-271.
D. Rawat, S. K. Sharma, A. Mahmoudi and S. R. Rao, “Cytogenetic Rationale for Probable Amphidiploids Origin of Dipcadi erythraeum Webb. & Berth—A Rare and Endemic Plant of Indian Thar Desert,” Caryologia, Vol. 64, No. 1, 2011, pp. 75-83.
V. D. Turkov and G. A. Shelepina, “Karyotype Characteristics of Cultivated Potato (Solanum tuberosum L.),” Dokl Vses Akad Skh IM VI Lenina, Vol. 11, 1974, pp. 18-19.
R. M. Devarmumath, S. C. Hiremath, S. R. Rao, A. Kumar and S. Bewal, “Genome Analysis of Finger Millet E. coracana by Interspecific Hybridization among Diploid Wild Species of Eleusine (Poaceae),” Cytologia, Vol. 70, 2005, pp. 427-434. doi:10.1508/cytologia.70.427
R. M. Devarmumath, S. C. Hiremath, S. R. Rao and A. Kumar, “Genome Interrelationship in the Genus Eleusine (Poaceae) as Revealed through Heteroploid Crosses,” Caryologia, Vol. 58, No. 4, 2005, pp. 300-307.
P. Scartezzini, F. Antognoni, L. Conte, A. Maxia, A. Troia and F. Poli, “Genetic and Phytochemical Difference between Some Indian and Italian Plants of Withania somnifera (L.) Dunal,” Natural Product Research: Formerly Natural Product Letters, Vol. 21, No. 10, 2007, pp. 923-932. doi:10.1080/14786410701500169
R. C. Verma, “Cytogenetics of Crotalaria and Phlox,” Ph.D. Thesis, University of Jodhpur, Jodhpur, 1981.
A. Kumar and S. R. Rao, “Chromosome Studies in Capparis deciduas,” Nucleus, Vol. 46, No. 1-2, 2003, pp. 95-98.
A. Kumar and S. R. Rao, “Cytological Investigations in Some Tree Species of Rajasthan II. Male Meiosis Studies in the Genus Anogeissus (DC.),” Caryologia, Vol. 55, No. 1, 2002, pp. 63-72.
V. Kumar and B. Subramaniam, “Chromosome Atlas of Flowering Plants of the Indian Subcontinent,” Botanical Survey of India, Ministry of Environment & Forests, Government of India, 1987.
Y. S. Bedi, B. S. Gill and S. S. Bir, “Cytological Evolution in Woody Taxa of Gamopetalae and Monochlamydae,” Journal of Cytology and Genetics, Vol. 20, 1985, pp. 162-203.
W. Gottschalk, “Die chromosomenstruktur der Solanceen unter Berucksichtigung phylogenetischer Fragestellungen,” Chromosoma, Vol. 6, 1954, pp. 539-626. doi:10.1007/BF01259953
G. R. Rao and A. Kumar, “Chromosome Pairing in Species Hybrids of Solanum nigrum Complex,” Current Science, Vol. 49, No. 22, 1980, pp. 868-870.
K. N. Subramanyam, H. Kishore and P. Misra, “Hybridization of Haploids of Potato in the Plains of India,” Current Science, Vol. 41, 1972, p. 580.
E. W. M. Van Breukelen, M. S. Ramanna and J. G. Hermsen, “Monohaploids (n=x=12) from Autotetraploid Solanum tuberosum (2n=4x=48) through Two Successive Cycles of Female Parthenogenesis,” Euphytica, Vol. 24, No. 3, 1975, pp. 567-574. doi:10.1007/BF00132892
M. Wagenvoort and W. Lange, “The Production of Aneudihaploids in Solanum tuberosum L. Group tuberosum (The Common Potato),” Euphytica, Vol. 24, No. 3, 1975, pp. 731-741. doi:10.1007/BF00132912
M. Sanjapa and N. Sathyananda, “In IOPB Chromosome Number Reports LXIV,” Taxon, Vol. 28, No. 4, 1979, pp. 391-408.
J. Venkateswarlu and M. K. Rao, “Breeding Systems, Cross Ability Relationships and Isolating Mechanisms in the Solanum nigrum Complex,” Cytologia, Vol. 37, 1972, pp. 317-326. doi:10.1508/cytologia.37.317
S. K. Sharma, S. Kumaria, P. Tandon and S. R. Rao, “Single Primer Amplification Reaction (SPAR) Reveals Inter- and Intra-Specific Natural Genetic Variation in Five Species of Cymbidium (Orchidaceae)” Gene, Vol. 483, No. 1-2, 2011, pp. 54-62. doi:10.1016/j.gene.2011.05.013
S. K. Sharma, D. Rawat, S. Kumar, A. Kumar, S. Kumaria and S. R. Rao, “Single Primer Amplification Reaction (SPAR) Reveals Intra-Specific Natural Variation in Prosopis cineraria (L.) Druce.,” Trees-Structure and Function, Vol. 24, No. 5, 2010, pp. 855-864. doi:10.1007/s00468-010-0455-4
S. N. Raina and Y. Mukai, “Detection of a Variable Number of 18S-5.8S-26S and 5S Ribosomal DNA Loci by Fluorescent in Situ Hybridization in Diploid and Tetraploid Arachis Species,” Genome, Vol. 42, No. 1, 1999, pp. 52-59.