Rapd analysis of a variant of banana (Musa sp.) cv. Grande Naine and its propagation via shoot tip culture

A morphological variant obtained from in vitro corm-derived plants of banana (Musa sp.) cv. Grande Naine (AAA) was evaluated up to harvest, and the genetic basis of variation was confirmed by the random amplified polymorphic DNA (RAPD). The corms formed during the multiplication phase of shoot tip-derived cultures of the cv. Grande Naine grown on Murashige and Skoog (MS) medium enriched with 13.3 mu M N-6-benzyladenine (BA) developed numerous morphological variants after transfer to MS medium with 6.66 mu M BA. The variant designated as CUDBT-B1, with distinct morphological features, was further evaluated. The morphological features of CUDBT-B1 were variegated leaf, pseudostem, bracts, ovary of the male flower and fruits, reduced height, decreased lamina length and breadth, and early flowering. These features were also manifested in the second-cycle progeny of CUDBT-B1. RAPD assay showed a marker DNA band of 1650 bp, and differential band intensity between the CUDBT-B1 and normal clone. CUDBT-B1 was multiplied using shoot tip culture, and the shoots were rooted on half-strength MS medium supplemented with 2.69 mu M alpha-naphthaleneacetic acid. All plantlets showed variegated leaves under field conditions.