An efficient Agrobacterium mediated genetic transformation protocol for the tomato (Solanum lycopersicum) cv. Arka Vikas was established. A comparison was made between hypocotyls and cotyledon on different regeneration media with and without Agrobacterium infection. Explants formed high-quality callus and regenerated on different types of media without Agrobacterium infection and kanamycin selectable media. But explants co-cultivated with Agrobacterium tumefaciens and in presence of kanamycin selection media, the callus induction and regeneration capability got reduced significantly. From these experiments by using cotyledonary explants an efficient protocol was developed for tomato using Agrobacterium tumefaciens mediated transformation. The transformation frequency was assessed in response to several different factors that include age of the explants, different types of explants (hypocotyls & cotyledons), three different Agrobacterium strains, infection time, co-cultivation time, initial kanamycin concentration during selection, different media combinations and different types of transformation methods. Eight day old cotyledonary explants were pre-cultured for 48 hrs on BAP (2 mg/l) and co-cultivated with Agrobacterium C58C1 harbouring PBIN plasmid was vacuum infiltrated for 5 min at 25 Hg pressure followed by incubation on BAP (2 mg/l) and Indole acetic acid (0.1 mg/l) for 48 hrs in dark, and transferred on zeatin (2 mg/l) and Indole acetic acid (0.1 mg/l) regeneration media with kanamycin as to create selection pressure. Maximum root induction from regenerated shoots was achieved at half strength MS media. The developed protocol showed 60.61 ± 0.5% efficiency of transformation for tomato cultivar Arka Vikas. The standardized transformation protocol is simple, efficient and does not require tobacco, petunia, tomato feed layers.
