Standardization of Callus derived in vitro Screening Technique for Salt Tolerance in Rice (Oryza sativa L.)

Abstract

In-vitro studies on salt tolerance were carried out with callus of three indica varieties, Karjat-5 (salt susceptible), Panvel-3 and FL-478 (salt tolerant). The study was conducted to obtain higher salt tolerant genotypes with variable characters of local rice varieties through somaclonal variations. Various concentration and combinations of plant growth regulators were supplemented with MS medium to develop friable callus and plantlet regeneration ability of mature embryo of rice. The calli were transferred to the proliferation medium of different concentration of NaCl to check the inherent capacity of calli to proliferate on medium under salt stress condition. Maximum percentage of callus induction observed in MS medium supplemented with 2.5 mg L-¹ 2,4-D along with 0.5 mg L^-1 BAP and 0.1 mg L^-1 NAA in all three varieties. Calli derived from the different concentration of 2, 4-D and other plant growth regulators were transferred on MS medium supplemented with various concentrations of BAP, Kinetin, NAA and IAA for plantlet regeneration. The weight of callus was decreased with increased in salt concentration. The variety FL- 478 showed proliferation of the callus upto 10 dS m-¹ salinity followed by Panvel^-3 (upto 8 dS m^-1 salinity) whereas the callus of Karjat-5 was survived only up to 4 dS m^-1 salinity. It indicates that variety FL- 478 and Panvel-3 are potential variety for development of novel somaclones for salinity tolerance as compared to Karjat-5. It was also observed that MS medium supplemented with 4 mg L^-1 BAP and 1 mg L^-1 IAA produced highest of plantlets for variety FL-478 (77.50) followed by Karjat-5 (69.17) and Panvel-3 (53.33).