In vitro Differentiation and Transformation of Elite Basmati Rice Varieties (Oryza sativa L.)
The aim of present study is to establish an efficient callus induction, regeneration and transformation system for basmati rice varieties. Seeds of four basmati rice varieties viz. Basmati-370, Pusa Sugandha-4, Vallabh Basmati-22 and Taroari were sterilized and incubated on MS medium with different concentrations of 2,4-D (1.5, 2.0, 2.5 mgL-1) . The best response of callus induction and proliferation for all the four basmati rice varieties was observed when 2 mg/l of 2, 4-D was used in the medium. The callus induction frequency was 94.1% for PS-4, 91.7% for B-370, 83.5% for VB-22 and 70.5% for Taroari. Twenty one day old maintained calli when transferred to regeneration media containing basic MS salts and vitamins with NAA 1 mgL -1, BAP 2 mgL-1 and Kinetin 2 mgL-1 showed 42.5% for B-370, 27.5% for PS-4, 12.5% for VB-22 and 15% for Taroari. The embryogenic calli derived from seed scutellum of two Basmati rice varieties i.e. B-370 and PS-4 were used for transformation by Agrobacterium tumefaciens strain EHA105 harboring pCAMBIA1305 with GUS (β-glucuronidase) and hpt (hygromycin phosphotransferase) genes for studying the transformation efficiency. From GUS histochemical analysis it was found that B-370 exhibited a transformation frequency of 6.6% whereas transformation frequency of PS-4 was found to be 5.3%.