Choudhary, J.MOHAMMED MOHSIN2020-12-192020-12-192020Mohammed M. And Choudhary J.https://krishikosh.egranth.ac.in/handle/1/5810156982Effect of Sowing Environments and Agro-chemicals in Mitigating Terminal Heat Stress and Productivity of WheatA field experiment was conducted during two consecutive rabi seasons of 2017-18 and 2018-19 at Instructional Farm, Department of Agronomy, Rajasthan College of Agriculture, Maharana Pratap University of Agriculture and Technology, Udaipur (Rajasthan). The treatments comprising four sowing environments [15th November, 30th November, 15th December and 30th December] and five agrochemicals [water spray, KCl 0.1 per cent, KCl 0.2 per cent, salicylic acid 100 ppm and salicylic acid 200 ppm], assigned, respectively to main and sub plots were replicated four times in split plot design. Wheat variety “Raj 4079” was used as a test crop. Results showed that crop sown on 15th November sowing environment recorded the maximum values of growth parameters (plant height, dry matter accumulation, crop growth rate, relative growth rate, flag leaf area, number of total tillers, days to 50 per cent heading and maturity) and yield attributes (effective tillers, ear length, grains ear-1 and test weight) and proved significantly superior over 30th November, 15th December and 30th December. Superior performance of growth parameters and yield attributes with 15th November sowing environment resulted in significant enhancement in grain, straw and biological yield. Sowing on 15th November recorded significantly higher grain (5573 kg ha-1), straw (8847 kg ha-1) and biological yield (14420 kg ha-1). Similarly, the maximum, chlorophyll content and relative water content were also recorded with 15th November sowing environment, however, the maximum grain protein content, canopy temperature and proline content were recorded with 30th December sowing environment. Significantly higher content and uptake of nitrogen, phosphorus and potassium by grain and straw were recorded * Ph.D. Scholar, Department of Agronomy, Rajasthan College of Agriculture, MPUAT, Udaipur -313001 ** Assistant Professor, Department of Agronomy, Rajasthan College of Agriculture, MPUAT, Udaipur -313001 with 15th November sowing environment. Results further indicated that significantly higher net returns (` 90201 ha-1) and B-C ratio (2.51) were also recorded with 15th November sowing environment. Results further indicated that foliar spray of salicylic acid 100 ppm being at par with salicylic acid 200 ppm recorded significantly higher growth parameters (plant height, dry matter accumulation, crop growth rate, relative growth rate, flag leaf area, number of total tillers, days to 50 per cent heading and maturity) and yield attributes (effective tillers, ear length, grains ear-1 and test weight) and proved superior over rest of the treatments. Higher values of growth parameters and growth attributes recorded in treatment salicylic acid 100 ppm resulted in maximum grain, straw and biological yield. Foliar spray of salicylic acid 100 ppm recorded 784 kg ha-1 higher pooled grain yield over water spray, 1076 kg ha-1 higher pooled straw yield over water spray and 1836 kg ha-1 higher pooled biological yield over water spray. Grain protein content, chlorophyll content and relative water content also increased significantly by agro-chemicals as compared to water spray. Further, nutrient content and uptake also increased significantly by agro-chemicals as compared to water spray. Foliar spray of salicylic acid 100 ppm resulted in significantly higher net return (` 75657 ha-1) and B-C ratio (2.13) compared to ` 58562 ha-1 and 1.65, respectively under water spray, respectively. Significant interactive effect of sowing environment 15th November along with foliar spray of salicylic acid 100 ppm were recorded with higher grain yield, net return and B-C ratio on pooled basis which was significantly superior over rest of the treatment combinations except 15th November along with salicylic acid 200 ppm.EnglishThesis