Report of genomic doubling in Cyamopsis tetragonoloba (L.) Taub. (Fabaceae): salient features and effects

Leguminous plants have always been highly valued to meet the nutritional necessities of human. An attempt to for genome multiplication in a legume crop is present in this study. Induced polyploidy as a technique has opened immense future prospects for the agriculture world. In this regard, in-vivo autopolyploidization experiment was planned on Cluster bean (Cyamopsis tetragonoloba (L.) Taub.). Present study is the successful documentation of the artificial induction of genome doubling by the application of colchicine i.e.C1 and is the first report of its successful establishment in the next generation (C2). Colchicine treatment was given to the young seedlings in two different concentrations of 0.2 and 0.4% for three different time durations. Results deciphered that chromosomal complement in case of diploid control plant is 2n=2x=14, whereas in the true polyploids it went on to be 2n=4x=28. Among the total of 148 seedlings that were treated with colchicine solution, 44 putative polyploid plants were monitored based on their distinctive morphological variations. Efficiency of 0.2% concentrations was found to be more than 0.4% concentrations. Palynological and anatomical evidences were also used for ascertaining polyploid organization to the putative plants with increment in size of stomata and pollen grains in the successful autotetraploids. Stomatal size is also an important determinant of ploidy where larger stomata with increase in chloroplast number was a typical feature among tetraploids. Cluster bean is a self-pollinated crop with narrow genetic base, but ploidy manipulation experiment might augment in broadening the genetic diversity. Procurement of large sized flower and seeds is a promising benchmark considering its improved aesthetic value. Autopolyploidization via colchicine has bestowed with the splendiferous act that offers prudent significance for diverse fields.