Whole plant regeneration from the shoot apex of Arachis hypogaea L.

Summary: Arachis hypogaea L. peanut, has been a difficult species to manipulate in tissue culture. Lack of a reliable and quick regeneration method for peanuts has proven to be one of the hindrances in the application of transformation protocols to the crop. A protocol to initiate shoot apex elongation and rooting of these shoots is described. This protocol was successful with two peanut cultivars. Shoot apices were isolated from germinated seedlings and placed on Murashige and Skoog salts containing N⁶-benzyladenine for shoot initiation. Once shoot elongation occurred, the explant was transferred to a rooting medium containing Murashige and Skoog salts and only one plant growth regulator, α-naphthalene acetic acid. In as few as 3 weeks, the explants began to root and could be transferred to soil. Forty-five percent of explants isolated from germinating peanut seeds would root on this medium. Elongation and rooting of the shoot apices were not hindered by the addition of an antibiotic to the medium, indicating that the regeneration method could be useful inAgrobacterium tume-faciens-mediated transformation protocols.