Rejuvenation influences indirect organogenesis from leaf explants of Pomegranate (Punica granatum L.) ‘Kandhari Kabuli’

Abstract

ABSTRACTSequential subculturing leads to a gradual physiological change in cells that may be termed ‘rejuvenation’. The effect of repetitive subculturing on callus induction and shoot regeneration from leaf explants of Punica granatum L. ‘Kandhari Kabuli’ were investigated. Surface-sterilised leaves were cultured on 1.0× Murashige and Skoog (MS) medium supplemented with 4.0 mg l–1 α-naphthaleneacetic acid (NAA) and 2.0 mg l–1 6-benzyladenine (BA) for callus induction. Shoots were regenerated from callus on 1.0× MS medium supplemented with 1.5 mg l–1 BA, 0.5 mg l–1 kinetin, and 0.25 mg l–1 NAA. Subculturing of callus onto fresh medium maintained the rate of shoot formation and substantially increased the production of shoot buds up to the second subculture. Following further subculture passages, a lower shoot regeneration potential from callus was observed. A maximum shoot bud induction from callus of 63.9% was observed at the second subculture passage. The rate of multiplication of in vitro shoots increased until the fourth subculture, then became constant. Similarly, in vitro rooting of micro-shoots increased up to the third subculture, followed by a decline during further subculturing.