ROOTING OF MICROSHOOTS OF MANGIFERA-INDICA L. CV AMRAPALI

A two-step protocol has been developed for in vitro rooting of microsh oots excised from plantlets obtained from nucellar somatic embryos of Amrapali cultivar of mango, Role of auxins, their concentrations, trea tment periods and culture illumination conditions for conferring compe tence for rooting have been ascertained, Indole-3-butyric acid (IBA) w as found to be the most potent among three auxins (IBA, indoleacetic a cid and a-naphthaleneacetic acid) tested for gaining competence for ef ficient rooting and root growth. Maximum rooting (89.71%) was found on auxin-free agar-gelled rooting medium after 24 h pulse treatment with 5.0 mg/l IBA in liquid root induction medium in dark, Dark condition favoured root induction and root growth, whereas light incubation (16 h photoperiod with 60 mu E m(-2) s(-1) light intensity) was inhibitory .