Meiotic behaviour and its implication on species inter-relationship in the genus (Linnaeus, 1753) (Zingiberaceae).

In this paper, detailed meiotic analysis was investigated in seven species of (Linnaeus, 1753) which can contribute significantly to our understanding about species inter-relationship, speciation and evolution. The species were divided into two groups viz., Group I having 2n = 42 ( Roxburgh, 1810, Mangaly & M.Sabu, 1993, Valeton & Zijp, 1917, and Roxburgh, 1800) and Group II with 2n = 63 ( Roxburgh, 1810, Linnaeus, 1753 and Valeton, 1918). Both groups display varying degree of chromosome associations. Group I species showed the prevalence of bivalents, however occasional quadrivalents besides univalents were also encountered. About 48% of the PMCs analyzed in showed 21 bivalents (II) meiotic configurations, 32% in and 16% in . Group II species as expected showed the presence of trivalents besides bivalents, univalents and quadrivalents. About 32% of the PMCs analyzed at MI in showed 21 trivalents (III) meiotic configurations, 24% in and 8% in . Overall, low frequency of multivalent associations as compared to bivalents indicates that is an allopolyploid complex. Moreover, x = 21 is too high a basic number, therefore, we suggest that the genus has evolved by hybridization of species with different chromosome numbers of 2n = 24 and 18, resulting in a dibasic amphidiploid species.