PLANT CELL BIOTECHNOLOGY AND MOLECULAR BIOLOGY

In vitro response of young inflorescence and leaf explants from three genotypes viz., hybrid cumbu (X6), medium duration inbred (PT 1479) and high yielding inbred (PT 4671) of pearlmillet was described. The basal medium used for callus induction and regeneration was MS with different levels of auxins and cytokinins. Of the different levels of 2, 4- D and kinetin used for callus induction, the combination of 2,4-D (2.5 mg/l) and kinetin (0.5 mg/l) was found to be suitable for callus induction. The callus induction frequency ranged from 2.50 to 86.67% and 5.00 to 93.33 % for leaf and young inflorescence explant in respectively. Highest percent of plant regeneration (86.25%) was recorded from leaf calli on MS medium supplemented with BAP (2 mg/l) and NAA (1mg/l) whereas BAP (2.0 mg/l) and IAA (1.0 mg/l) combination gave maximum regeneration frequency (91.25%) with the inflorescence derived calli. Zeatin (2.0 mg/l) and IBA (1.5 mg/l) combination for leaf calli derived regenerants and IBA (1.5 mg/l) alone for young inflorescence calli derived regenerants were found to be better for root initiation. Among the three genotypes studied, the morphogenetic potential was found to be high in hybrid cumbu (X6), followed by medium duration inbred (PT 1479) and high yielding inbred (PT 4671). The regenerated green plants were transferred to green house. About 23 regenerants were transferred to the field condition and fourteen regenerants have been successfully established.