Effect of thermal environments and weed control treatments on agrometeorological indices of wheat (Triticum aestvium L.)

A field experiment was conducted during rabi season of 2023-24 and 2024-25 to study the agrometeorological indices viz. accumulated growing degree days (GDD), helio-thermal unit (HTU), photo-thermal unit (PTU) at different phenological stages of wheat variety HI-1544 under different herbicidal mixtures and thermal environments. To address this, a two-year field experiment (2023-24 and 2024-25) was conducted at the Farm B, College of Agriculture, GanjBasoda, District Vidisha (M.P.). The experiment was conducted in split plot design with three thermal environments (15^th November, 30^th November and 15^th December) and 6 weed control treatments (W₁: Fenoxaprop-p-ethyl + Metribuzin, W₂: Clodinafop-propargyl + Metsulfuron Methyl, W₃: Sulfosulfuron + Metsulfuron Methyl, W_4: Metribuzin + 2,4-D, W_5: single hand weeding at 30 DAS and W_6: Weedy check) with three replications. Results of present study revealed that the crop sown on thermal environment of 15^th November took maximum calendar days, total growing degree days, photo thermal unit, helio-thermal unit and heat use efficiency to attained different phenological stages till maturity. Among the weed control treatments, maximum calendar days, agrometeorological indices (GDD, HTU, PTU) was higher under W₃ (Sulfosulfuron + Metsulfuron Methyl).