Abstract:

Twelve plantain ecotypes were characterized for molecular variability using random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) markers. Out of the 60 RAPD and 40 ISSR primers tested, 16 RAPD and 14 ISSR primers were found polymorphic, and were used for molecular profiling of the plantain ecotypes. The average number of bands per primer, average number of polymorphic bands per primer, mean polymorphic information content (PIC) value, resolving power (Rp), and marker indices (MI) for RAPD primers were 8.63, 3.25, 0.87, 15.49, and 2.86, whereas the respective values for the ISSR assay were 7.93, 4.14, 0.85, 12.49, and 3.55. The genetic similarity coefficient was calculated using the Jaccard coefficient. The unweighted pair group method with arithmetic averages (UPGMA)-based clustering pattern remained more or less similar for RAPD, ISSR, and combined RAPD and ISSR data. Clustering was strongly supported by high bootstrap values. The genotypes Njockkon and Changalikodan (similarity coefficient > 0.94) and Manjeri Nendran (a) and Manjeri Nendran (b) (similarity coefficient > 0.89) were more closely related than the other ecotypes. The principal component analysis (PCA) showed results similar to those of the dendrogram. The results revealed that ISSR would be a better tool than RAPD for evaluation of genetic diversity in plantain ecotypes. Further, huge variability exists among the plantain ecotypes, which can be utilized for germplasm collection, in situ conservation, and development of high yielding nutritionally superior cultivars in Musa L. breeding programs.

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