Induced mutations for enhancing variability of banana (Musa spp.) shoot tip cultures using ethyl methanesulphonate (EMS).

The aim of this study was to induce variations in banana cultivars through in vitro mutagenesis by treating the shoot tips with varying doses (150, 200 and 250 mM) and time periods (30 and 60 min) of EMS and to apply RAPD analysis for discovery of genetic polymorphism among the variants. The results of analysis of variance indicated that the average number of shoots per explant, survival (%) and fresh weight of treated shoot tips were influenced by EMS doses and gave significant differences caused by time period of treatments. The highest percentage (31.04 ± 0.99) of dormant explants was observed in 'Rastali' with 200 mM EMS for 30 min treatment. Whilst, in 'Berangan Intan' and 'Berangan', 60 min/ 250 and 30 min/ 200 mM indicated the maximum increase in terms of dormant explants production. Based on the proliferation rate of 'Berangan Intan', 'Berangan' and 'Rastali', LD 50 was estimated 189.8, 177.58 and 152.04 mM for 30 min duration treatment and 154.17, 148.21 and 141.83 mM for 60 min duration treatment respectively. After three months of culture, percentage of phenotypic variations derived from mutated shoot tips indicated an increase of 10 to 14 % with 60 min/ 200 mM and 30 min/ 250 mM of EMS treatments compared to those of controls. At the molecular level, the RAPD primers opc01, opc04, opa11, opa14, opd16, opk03 exhibited different amplification patterns in the variants. The results showed the variability among lines isolated through tissue culture and EMS mutagenesis, confirmed by using RAPD markers for banana.