Studies on the phasic duration and thermal unit at different phenophases of rice (Oryza sativa L.) cultivars under varying crop growing environment

A field experiment was conducted during kharif season 2018 entitled “Studies on the phasic duration and thermal unit at different phenophases of rice (Oryza sativa L.) cultivars under varying crop growing environment.” in sandy loam soil of N.D. University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.). The experiment consisted of nine treatment combinations comprised of three transplanting dates viz. July 15th, July 25th and August 04th and three varieties viz., NDR-97, NDR-2064 and BPT-5204. Results reveal that different phenophases of rice markedly varied with only dates of transplanting but also different weather variables which ultimately create the different crop growing environment to harvest the yield accordingly. The different growing environment and rice cultivars varied markedly to the days taken to phenophases maximum days (113) taken to maturity were recorded when crop was transplanted on July 15th. Among the cultivars maximum days taken to maturity were recorded with BPT-5204(130 days) followed by NDR-2064 (110 days) and minimum days in NDR-97 (90 days). Among the cultivars it is evident that accumulated thermal unit was highest in cultivar BPT-5204 (2223.5 °C days) followed by NDR-2064 (2079.9 °C days).