In Vitro Selection of Cell Lines in Punica granatum L. (Daru) Against Bacterial Blight

Disease resistant cell lines of wild pomegranate were selected against bacterial blight caused by Xanthomonas axonopodis pv. punicae. Callus from cotyledon explants was exposed to purified toxic culture filtrate produced by bacteria. Initiation, maintenance of callus as well as selection process was carried out on MS medium supplemented with 2.0 mg/l BAP and 4.0 mg/l NAA. Resistant lines were selected at 40 % level of culture filtrate after two cycles of selection. Microshoots from selected calli were regenerated on medium containing 2.0 mg/l BAP, 1.5 mg/l Kinetin and 3.0 mg/l GA3. Fresh weight of callus increased progressively up to third subculture passage while shoot bud induction from selected calli was observed only after third subculturing. The selected microshoots were rooted on half strength MS medium containing 400 mg/l activated charcoal medium. After in vitro testing of shoots regenerated from selected calli four resistant plantlets were obtained.