Influence of explanting season on in vitro multiplication of the medicinal herb, Tridax procumbens L.

Abstract

A protocol for complete regeneration of Tridax procumbens, a medicinally important plant, was accomplished through in vitro culturing. From nodal segments explants, high percentage of bud break and multiple shoot formation was induced between July and September on MS medium supplemented with BAP (1 mg L-1). Rooting of the excised shoots from secondary cultures was excellent on halfstrength MS medium having 1 mg L-1 IBA. Micropropagated plants when transplanted on garden soil flowered after 6 - 8 weeks. Explants sampled during December had low percentage of bud break and less shoot number per explant. Epicuticular wax (EW) and cuticular transpiration varied in the leaves collected during July and December; while under in vitro conditions, no marked differences were observed in regards to the 2 parameters. The epicuticular contents correlated with the rate of cuticular transpiration. The adaptive significance of EW during December is discussed.