―SHORT COMMUNICATION― Agrobacterium rhizogenes mediated hairy root induction in Oxystelma esculentum (L.f) R.Br. ROBERT JEYACHANDRAN* and AYYAVO MAHESH Department of Plant Biology and Plant Biotechnology, St. Joseph’s College, Tiruchirappalli – 620 002, India Abstract This report describes a technique to induce hairy roots in Oxystelma esculentum (L.f) R.Br. Explants of hypocotyls and cotyledons derived from in vitro germinated seedlings were aseptically co-cultivated with Agrobacterium rhizogenes strain 15834 and cultured in half- and full-strength MS and B5 basic media. The infected hypocotyls responded well and genetic transformation was observed with reference to the total biomass and number of hairy roots. Transgenic plants often exhibited altered phenotypes compared with controls. The response of hairy root induction in hypocotyls was found to be 96%, the mean biomass 83.8±0.48 g and the mean number of hairy roots 35.6±0.97. The hairy root syndrome is displaced by plants regenerated from Ri-transformed roots. Combined expression of the rol (A, B and C) loci of A. rhizogenes was observed and Ri-plasmid was involved in the establishment of the hairy root syndrome.   < back .