Indian Journal of Plant Physiology

The shoot regeneration response from different explants, viz. cotyledon, cotyledonary node and petiolule, of the most popular Indian cultivar, JL-24 of peanut (Arachis hypogaea L.), was evaluated by culturing on Murashige and Skoog medium containing B₅ vitamins supplemented with different growth regulators. Shoot bud initiation, proliferation and subsequent development into shoots were found to be superior from cotyledonary node explants in comparison to other explants. High frequency (69% direct shoot regeneration from cotyledonary node was observed on MS medium with 4.0 mg l⁻¹ BAP and 0.2 mg l⁻¹ NAA. The shoots elongated upon transfer to MS medium with lower concentrations o BAP. Elongated shoots could be continuously harvested at 15 days interval for a period of 75 to 90 days. The regenerated shoots were rooted at a high frequency of 84.5% on MS medium containing 1.0 mg l⁻¹ NAA. The regenerated plantlets survived to maturity in greenhouse, flowered, set pods and seed normally. This protocol could be very efficiently used for transformation studies.