Dry Matter Partitioning and Productivity of Wheat (Triticum aestivum L.) as Influenced by Sowing Thermal Regimes and Bio-regulators

A field experiment was carried out during the rabi seasons of 2016-17 and 2017-18 at Agronomy Farm, S.K.N. Agriculture University, Jobner, Jaipur, Rajasthan, to evaluate the effect of sowing at different thermal regimes and foliar sprays of bio-regulators on growth and yield of wheat. The treatments comprised three sowings (22ºC, 20ºC and 18ºC) and eight bio-regulators (control, water spray, SA @ 100 ppm, SA @ 200 ppm, TSA @ 100 ppm, TSA @ 200 ppm, TGA @ 100 ppm and TGA @ 200 ppm). The experiment was conducted in split plot design with 4 replications. Wheat sown at 20ºC showed superior performance in respect of dry-matter partitioning and yield parameters, i.e. grain, straw biological and yields as compared to sowing at 22ºC and 18ºC. Amongst the bio-regulators options, an application of SA @ 200 ppm resulted in better performance, being comparable with those of TSA @ 200 ppm and TGA @ 200 ppm. Crop sown at 20ºC along with SA @ 200 ppm was found to be a better option for maximum dry matter accumulation and productivity of wheat under heat stress.