In vitro plant regeneration from mature seeds of finger millet (Eleusine coracana) through somatic embryogenesis

Abstract

Mature seeds of two genotypes of finger millet, viz., PR 202 and PES 400, were cultured on 20 different callus induction media containing four levels of 2,4-d (1, 1.5, 2.0 and 2.5 mg l−1) alone or in combination with two levels of cytokinin (0.5 and 1.0 mg l−1 kinetin or BAP). 2,4-d was found to be most effective for callus induction and development when combined with kinetin. Genotypic response for embryogenic callus development ranged from 29.5 to 78.2 % for PR 202 and 10 to 35.7 % for PES 400. After 45–50 days of culture, calli were transferred in light to develop into green nodular calli. Plantlets were obtained by transferring the green nodular embryogenic calli onto regeneration media containing different concentrations and combinations of GA3, kinetin and BAP. Kinetin was found to be more effective for shoot regeneration as compared to BAP. When Callus derived from BAP containing media were transferred on regeneration media containing GA3 alone or with BAP, developed shoots were either devoid of roots or had few thin roots. These shoots were rooted on MS basal media and MS media supplemented with IBA (0.5 or 1.0 mg l−1), NAA (1 mg l−1) and IBA + NAA (0.5 mg l−1 each). Rooting media containing 0.5 mg l−1 IBA and 0.5 mg l−1 NAA showed remarkable rooting response, inducing a thick bunch of 11.5–12 healthy, white and long roots per shoot. Regenerated plants were transferred to pots containing sterilized soil:sand:vermiculite:FYM (2:2:2:1) and were irrigated with Hoagland solution. Regenerated plants grew well and were successfully established in soil.