Thermal indices in relation to crop phenology of wheat (Triticum aestivum L.) crop grown under agro-climatic conditions of Eastern Uttar Pradesh

Field experiments were conducted during rabi seasons of 20021-22 and 20022-23 at Agrometeorological Research Farm, Acharya Narendra Dev University of Agriculture & Technology, Kumarganj ,Ayodhya, Uttar Pradesh to study phenology and GDD, PTU, HTU and PTI for wheat crop at Eastern zone of Uttar Pradesh. Wheat crop were sown on three date of sowings viz. 15^th November 1^st December and 15 December during rabi season in both year. Results revealed that mean GDD, HTU, PTU for wheat crop were 1476, 10272, 19657 and 1453, 10112, 19171 respectively. Physiological maturity can be predicted for wheat by using GDD, HTU, PTU with R² 0.97. During 2021-2022 the HUE for wheat was 2.84 kg grain/ha degree days^-1 with grain yield 4200 kg/ha and during 2022-2023 HUE was 2.81 kg grain/ha degree days^-1 with grain yield 4089 kg/ha.