IN-VITRO CALLUS-CULTURE AND PLANT-REGENERATION FROM DIFFERENT EXPLANTS OF GROUNDNUT (ARACHIS-HYPOGAEA L)

Callus induction and morphogenesis from different groundnut explants w ere tested on MS salts supplemented with B5 vitamins, different concen trations and combinations of IAA, NAA, IBA, KIN and BAP. The explants were hypocotry, epicotyl, axillary bud, cotyledonary node, immature le af and immature embryos. The frequency of callus induction increased w ith increasing concentrations of auxins, the optimal levels being 3.0 mg/l of IAA or NAA and 0.5 mg/l of KIN. Among the explants, immature l eaf was found to be most efficient explant in producing callus. Shoots were induced from callus cultures of hypocotyl, epicotyl, axillary bu d, cotyledonary node, immature leaf and immature embryos with varying frequencies in the medium containing IAA or NAA (0.5 mg/l) and KIN or BAP (0.5 - 2.0 mg/l). Maximum number of multiple shoots were obtained from cotyledonary node explant. The regenerated shoots rooted best on MS medium containing 2.0 mg/l of IBA and 0.2 mg/l of KIN. Regenerated plants were normally fertile. In vitro produced plantlets were transfe rred to soil and placed in glass house and they developed successfully , matured, and set seed. No phenotypic variants were observed among an y of the plants produced in these experiments. Thus, this regeneration system offers an additional and more efficient tool for groundnut bio technology research promrammes.