Analyses of genetic relationships in Nelumbo nucifera using atpB-rbcL chloroplast spacer and AFLP markers

Despite the economic importance of Nelumbo nucifera, there have been meagre studies on genetic diversity with few accessions in the species. In the present study a total of 120 accessions in wild lotus and three cultivated types (flower lotus, seed lotus and rhizome lotus) were analyzed with atpB-rbcL chloroplast spacer and AFLP marker to determine their genetic relationships. The analysis of the atpB-rbcL chloroplast spacer revealed no significant genetic differentiation between wild lotus and cultivars and among the three cultivated types. The results of the AFLP analysis further proved the high genetic similarities among them. AFLP cluster indicated that the wild lotus did not distribute in a single independent group but interspersed in the different flower lotus groups. It meant that the flower lotus probably originated from different groups of the wild lotus. Nevertheless, seed lotus and rhizome lotus only clustered in one group with a quite high genetic similarity indicating that they had close genetic relationships. The quite high similarity among the accessions of seed and rhizome lotus indicated that the two types might have arisen from a single domestication event that led to a genetic bottleneck that limited diversity within the two types.