Response of Groundnut Varieties to Plant Growth Regulator (BAP) to Induce Direct Organogenesis

An efficient protocol for plant regeneration has been developed for crop improvement programs. The present study was designed to assess the regeneration response of cotyledonary node explant taken from the germinating seeds of peanut (Arachis hypogaea L.). Complete plants were regenerated from in vitro cultured sectioned cotyledonary nodes. Multiple shoots arose on 6-benzylaminopurine (BAP) supplemented Murashige and Skoog medium (1-50 mg L ), with maximum production occurring at 15 mg L in most varieties. 1 1 Lower concentrations of BAP were proved to be effective in inducing multiple shooting whereas higher concentrations proved to be inhibitory in all the genotypes. Shooting potential of all the genotypes varied under the influence of BAP that might be due to genotypic variations among the varieties. Flowering was observed in PBS24030 genotype on 1 mg L NAA. On 5 mg L BAP, extensive flowering was obtained in 1 1 RG-141 genotype. Rooting of isolated shoots in four genotypes (HNG-10, PBS24030, M-335 and M-13) was observed on MS supplemented with 1 mg L NAA, while a combination of 1 mg L NAA and 0.5 mg L IBA 1 1 1 was required for rooting in RG-141. The rooted plantlets were transferred to plastic cups containing a mixture of soil: sand: farmyard manure/vermicompost (3:1:1 w/w) in the growth chamber for 7-10 days. Subsequently, the newly formed plantlets were transferred to field, where they flowered and set viable seeds. No phenotypic variants were observed among any of the plants produced in these experiments. Thus, this system permits in vitro production of morphologically normal peanut plants with high frequencies.