The Effect of Mannitol and Nano Urea on Terminal Heat Stress on Wheat (Triticum aestivum L.)

The present investigation was conducted during Rabi season, 2022-23 & 2023-24 at the student instructional farm (SIF) of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya- 224229 (U.P.). The experiment was conducted in randomized block design with three replications, seven treatments and wheat variety (HD 2967). The treatment was comprised of control distilled water spray, Mannitol 25, 50, 100 ppm and Nano urea 25, 50, 100 ppm respectively, which was foliar sprayed at 30 DAS. The observations have been studied on growth, bio-chemical, yield and yield attributes of wheat. Observations were recorded at 60, 90 DAS and at maturity stages for timely sowing (15 November) and late sowing (15 December). However, yield and yield parameters were taken at the time of harvesting of the crop. Foliar spray of mannitol and nano urea were performed well at 60, 90 DAS and at maturity parameters. Foliar application of nano urea with 25 ppm was recorded superior on plant height (cm), dry weight plant-1 (g), chlorophyll content in leaves (SPAD value), Catalase activity (g-1 fresh weight min-1), Peroxidase activity (mg g-1 fresh weight min-1), Super oxide dismutase activity (mg g-1 fresh weight min-1) However, yield and yield attributes viz length of spike, number of tillers plant-1, number of grains spike-1, grain yield plant-1 It is concluded from the result that foliar spray of nano urea 25 ppm was found most effective to increasing all characters and yield parameters of wheat.