Assessment of Various Factors Involved in the Tissue Culture System of Rice

摘要

To optimize conditions for an efficient embryogenic callus induction and plant regeneration from mature seeds of japonica rice cultivar Xiushui 11 and indica cultivar XC95, different factors such as plant growth regulators, casein hydrolysate, carbohydrate source and concentration, and various gelation conditions including gel type for callus induction and phyta gel concentration for shoot regeneration were studied in detail to determine their role in the system. Overall, induction of embryogenic callus in case of Xiushui 11 was the most efficient (67.2%) in the media supplemented with 2 mg/L 2,4-D, 3% sucrose and 0.8% agar while in case of XC95, 2 mg/L of 2,4-D combined with 0.5 mg/L of BAP and NAA generated the best result (61.2%). Inclusion of 0.3% agarose (pure form) or phyta gel further enhanced the callus induction efficiency (80%) in Xiusui 11. Higher concentration (300-500 mg/L) of casein hydrolysate was found to significantly inhibit the browning of calli in XC95. Role of cytokinin and phyta gel concentration was critical for shoot regeneration in both classes of rice. Increased strength of phyta gel was observed to enhance the shoot regeneration frequency. The optimal concentration of 2 mg/L and 3 mg/L for KT was necessary for higher differentiation frequency supplemented with 0.5% and 0.6% phyta gel in case of japonica and indica rice, respectively.