Standardization of high efficient and rapid regeneration protocol for Agrobacterium mediated transformation of tomato (Solanum lycopersicum L.) cv. Pusa Ruby, Vaibhav and Arka Meghali

In the present investigation, three tomato cultivars Pusa Ruby, Vaibhav and Arkamegali (Solanum lycopersicum L.) were selected for multiple shoot induction. The explants cotyledon, hypocotyl and epicotyl of all the cultivars of tomato were cultured on MS medium fortified with different concentrations of BAP (1.0 to 4.0 mg/l), TDZ (1.0 to 4.0 mg/l), Zeatin (0.5 to 1.0 mg/l), AS (5.0 to 20 mg/l) and 0.1 mg/l IAA . Adventitious shoot buds were induced at the cut ends of the explants after three weeks of culture. The shoots were induced from cotyledon, hypocotyl and epicotyl explants on different concentrations of growth regulators (RM 1 to RM 10). Among ten media combinations tested, RM 9 was the best combination for induction of shoots from cotyledon, hypocotyl and epicotyl explants compared to RM 2. The highest number of shoots was induced on 0.5 mg/l Zn + 10 mg/l AS + 0.1 mg/l IAA (RM 9) followed by 2.0 mg/l BAP + 10 mg/l AS + 0.1mg/l IAA (RM 2). Among the three genotypes tested Pusa ruby showed highest number of shoots per explant followed by Vaibhav and Arkamegali. Highest number of adventitious shoots was induced from cotyledonory compared to hypocotyl and epicotyl explants in Pusa ruby and Arka meghali, where as Vaibhav induced highest shoots from epicotyl explants. Rooting was achieved on MS medium supplemented with 0.1 mg/l IAA in all the genotypes. Hence the plant regeneration was found to be influenced by the genotype, different explants with hormonal combinations in the media.