Analysis of the Genetic Stability of Banana Tissue Culture Propagated Plantlets cv. Ney Poovan (AB) Using Morphological and Molecular Markers

Abstract

The present study was carried out to monitor somaclonal variations of banana cv. Ney Poovan (AB) during micropropagation using random amplified polymorphic DNA (RAPD). Sword suckers were used as explants and regenerated on MS media supplemented with BAP alone, BAP + Kinetin and TDZ at varying levels of concentrations. The regenerated shoots were again subcultured on MS medium fortified with plant growth regulators at different concentrations. Rooting was obtained on ½ MS medium supplemented with 2.00 mg/l IBA and 2 g/l of activated charcoal. Rooted plantlets were observed visually for phenotypic appearances and then transferred in greenhouse for hardening. After one month the hardened plants of banana were screened for genetic stability using RAPD primers. For molecular analysis 6 operon primers were used and all of them showed amplification. 04 primers (OPC 04, OPC 20, OPK 14, OPM 12) amplified unambiguous, readable and showed monomorphic bands, whereas, 02 primers (OPB 04 and OPD 07) gave polymorphic banding patterns. A total of 296 scorable band classes were produced by 6 RAPD primers tested in banana cv., Ney Poovan. The number of bands for each primer varied from 28 to 80 with an average of 49.33 bands per primer. The results obtained using RAPD showed recordable monomorphic and polymorphic band patterns. RAPD had shown 94.10 % monomorphism and 5.90 % polymorphism. In the present investigation, the percentage of polymorphism was 5.90 % which is under permissible limit. In banana, up to 10% variation is permitted (as practiced by commercial micropropagation outfits) owing to the flexible genetic make-up of the crop.