Sixteen collections of the wild Musa species, Musa balbisiana Colla collected from different regions of India were studied for their intraspecific relationships using random amplified polymorphic DNA (RAPD) markers. Out of 80 primers screened, 34 primers produced reproducible bands and four primers among them showing polymorphic bands were used. In all, 43 DNA fragments were amplified averaging 10.75 per primer. Of these, 31 amplified fragments showed polymorphism (averaging of 7.75 per primer). The extent of polymorphism (74.6%) has indicated the existence of considerable variation at the DNA level within the species. The 16 accessions were clustered into four as against seven clusters obtained through morphotaxonomic characterization. The inter relationships based on geographical origin in comparison with molecular characterization have been discussed.

Bananas are vital for food security in many countries, and half of banana production relies solely on ‘Cavendish’ (AAA), which is presently threatened by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc) tropical race 4. This particular virulent Foc strain was also found to attack other banana varieties of commercial importance. As there is no single effective management practice available so far, this study was undertaken to determine resistant sources from the genotype collection available at the ICAR-National Research Centre for Banana, Tiruchirappalli, Tamil Nadu, India for direct use by farmers and/or in breeding programmes to develop resistant hybrids. A total of 258 genotypes of different ploidies and genomic constitutions were tested against Foc race 1 (VCG 0124). In total, 19 genotypes (AA Unique-6, BB type-2, AAA Unique-1, AAA Cavendish-1, AAB Mysore-3, AAB Pome-1, AAB Plantain-4 and AAAB-1) were found to be immune; eight genotypes (AA Unique-1, BB type-3, AAA Cavendish-1, AAB Mysore-1, AAB Unique-1, AAB Plantain-1) were highly resistant; and nine genotypes (AA Unique-1, AAA Cavendish-3, AAB Silk-1, AAB Pome-4) were resistant. The genotypes that are resistant to the virulent Foc race 1 (VCG 0124) strain can be exploited directly for commercialization and/or in breeding programs to develop resistant hybrids.

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