Ephemeral rice breeding: Viable approach for upland water stress tolerance

Two experiments were undertaken simultaneously (early generation evaluation and advanced generation evaluation respectively) at SGCARS, Jagdalpur, IGKV, Raipur, Chhattisgarh, to indentify and analyze ephemeral genotypes for suitability in rainfed upland rice production ecology. In early generation testing, mean plot flowering was recorded to be 72 DAS, plant height 83cm, panicles per square meter 212 and grain yield to be 2330kg/ha. Regional check Vandana and CRR-676-1 flowered earliest by 68 DAS followed by CRR-627-35-1-5 (69 DAS) and CRR-507-11-B-1 and CRR-605-23-1. The CRR-433-2-1-1 flowered latest by 83 DAS and as per hypothesis;yield was considerably reduced since plant could not develop optimum source-sink balance and carbon accumulation in seeds eventually. Regarding, crop yield five genotypes placed above the local check, namely CRR-597-5-1 (29.47%), the national check i.e. Anjali (21.05%), CRR-676-1 (15.79%), CRR-433-2-1-1 (10.53%) and the regional check i.e. Vandana (7.92%). Among advanced material, interestingly, the highest yielder genotype flowered earliest (69 DAS) that suggests the accomplishment of crop growth and physio-biochemical development while utilizing of soil and environmental reserve appropriately. On overall mean yield was 2349kg/ha, whereas genotype CRR-616-B-2-54-1 derived ranked 1st with 2718 kg/ha yield, 69 days of flowering duration and short bold grains. The bimodal experiment concludes that short life cycle and rapid veg-repo shift is critical for survival in rainfed rice growing regions and those genotypes which maintain the physiological buffer at the shift will be able to sustain genetic yield potential.