Induction and field performance of in vitro microrhizomes of turmeric (Curcuma longa L.) for production of disease free planting material

This study was aimed at developing a technology for production of disease free planting material through in vitro micro rhizomes in turmeric. The effects of various concentrations of MS salt, sucrose, culture duration and different growth regulators viz., benzyladenine (BA), kinetin and α- naphthalene acetic acid (NAA) on in vitro rhizome formation of turmeric (Curcuma longa L.) were studied. In vitro rhizome formation occurred in all the above treatments. Three fourth strength of Murashige and Skoog's (MS) medium supplemented with 1 mg/l BA, 0.5 mg/l α- NAA, 9% sucrose, 0.8% agar is the best for microrhizome induction in turmeric. The microrhizome derived plants, due its small size, on field evaluation showed a significant increase in number of tillers, number of leaves but showed slight reduction in fresh rhizome size and weight per plant when compared with conventionally propagated plants. RAPD profiling indicated genetic uniformity among micro rhizome derived plants. The disease free nature of the rhizomes produced, give the micro rhizomes an advantage over conventional propagules. This is a viable technology for production of disease free planting material in turmeric, where most of the diseases are spread through seed rhizomes.