Studies on the Thermal Unit and Heat Use Efficiency Requirement of the Mustard Crop (Brassica juncea L.) under Different Ambient Temperatures and Cultivars

A field experiment was directed during the rabi period of 2020-21 in the sandy topsoil of A.N.D. University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.). The investigation was directed in Split Plot Design (S.P.D.), comprising of three growing environments/ambient temperature viz. 31st October (22.6°C), 10th November(21.2°C), 20th November(19.4°C) and three cultivars i.e. NDR-8501 (V1), Kranti (V2) and Varuna (V3). The experiment was replicated four times. Results revealed that the highest thermal unit (1667.2 days) and thermal use efficiency (0.61 g/m²/ºdays) was recorded at developing climate/encompassing temperature of 31st October (T1) (22.6°C)while least gathered hotness units from planting to development (1468.9ºC days) was seen under the developing climate/surrounding temperature of twentieth November. The late-planted mustard crop recorded the least GDD prerequisite at every one of the stages. The least Thermal use proficiency from planting to development 0.435g/m²/ºdays was seen under developing climate/encompassing temperature (tenth November)(21.2°C). Late planted cultivars recorded the least warm use effectiveness necessity at all stages.