New Multiple Abiotic Stress Tolerant Rice Variety Developed from Combining Tissue Culture and Gamma Irradiation

The changing global climate causes the melting of polar ice caps, thereby increasing sea water levels. The increase in sea level causes saltwater intrusion in the inland, affecting rice production near coastal regions. The development of resilient rice varieties remains the most sustainable mitigation to cope with climate change. The biotechnological approaches such as induced mutation could facilitate the development of climate change-resilient rice. In vitro mutation, a technique of combining tissue culture and physical irradiation of FR13A generated a mutant population, from which PR48421-FR13A-IVM2012DS-1-7-4 was among the lines selected. The line was subjected to abiotic stress tolerance screening, viz. drought, saline, and submergence, of which it was found to be tolerant. Field performance for grain yield led to the nomination of the line to the National Cooperative Test (NCT). Under NCT, the line was evaluated in three saline-prone sites from the 2020 Dry Season (DS) to the 2021 Wet Season (WS). The mean yield of the line across seasons and locations was 3,069 kg ha^–1, which is 7.7% higher than the check variety (NSIC Rc392), which incurred a mean yield of 2,855 kg ha^–1. This yield advantage, together with its good reaction to pests and diseases plus acceptable grain quality, led to its recommendation to the National Seed Industry Council (NSIC) and was approved and released as a new variety for saline-prone rice environments in 2022 as NSIC 2022 Rc686 or Salinas 39. The release of NSIC 2022 Rc686 proved the efficiency of mutation breeding in developing climate-resilient rice varieties.