Morphological and Molecular Characterisation of Somaclonal Variants in Tissue Culture Banana Variety Grand Naine

Banana (Musa paradisiaca) is herbaceous plant belonging to the family Musaceae of the genus Musa and isnative to the tropical region of South East Asia. Banana is cultivated throughout tropics and subtropics.. In recent years, tissue culture serves as a tool to mass multiply virus free planting material. However, the greatest disadvantages of tissue culture are somaclonal variants. Somaclonal variants (offtypes) induced during the in vitro multiplication process is major drawback for mass propagation of banana as planting materials. Field surveys were conducted during 2012–14 to evaluate banana fields for incidence of viruses and off types (somaclonal variants) in selected Banana growing areas of Bangalore covering Mandya, Mysore, Chikballapura, Bangalore Rural and Bangalore Urban districts where area under tissue culture banana was relatively high, during 2012–14. Results on survey of off types in tissue culture propagated banana plantations indicated the occurrence of six distinct types of somaclonal variants. The incidence of somaclonal variants ranged from 0.00 to 9.40 per cent with a mean of 2.95 per cent. Twenty-five ISSR markers reported by various workersfor detecting somaclonal variants in tissue culture variety G-9 were screened to detect off types obtained during field surveys. A total of six somaclonal variants collected during survey were screened using 25 ISSR markers for each variant. Out of six variants, only one variant viz., variant with chimeric leaves was detected using available ISSR markers. And out of 25 ISSRmarkers, only three ISSR markers viz., IG-1, IG-12 and IG-13 produced polymorphic bands in variant with chimeric leaves. These three markers produced profile distinct fromthe expectedprofile of Grand Naine true to type plants.