Optimization of regeneration using differential growth regulators in indica rice cultivars.

Paddy is a staple crop and being grown in major parts of India, but similarly it is facing some major challenges like abiotic stresses (drought, salinity, etc.) by which its productivity is greatly affected. De-husked seeds of 21 cultivars of indica rice were cultured onto MS medium for screening of their micropropagation capabilities. All the selected cultivars are being cultivated by farmers of Andhra Pradesh and Rajasthan states of India, these cultivars bear good quality of grain and high yield. Similarly, both states are facing the problem of drought so; we selected these cultivars for the micropropagation and transformation studies. The induction of callus and regeneration in these selected cultivars were achieved on MS culture medium with supplementation of various growth regulators. Maximum callus induction and regeneration frequency were observed in Sambha mahsuri at the concentration of 3.0 mg L of 2,4-D and BAP (5.0 mg L) while the moderate response achieved in other cultivars of rice. Sambha mahsuri showed promising results in terms of callus induction frequency, and regeneration potentialities of embryogenic callus so, there is need to develop a rice cultivars that could thrive under drought condition if the country is to sustain rice production. Finally, regenerated plantlets were successfully transferred to natural conditions (in pots) after acclimatization.