Field experiments were conducted during the rabi seasons of 2014-15 and 2015-16 at Research Farm of the Department of Agricultural Meteorology, Chaudhary Charan Singh Haryana Agricultural University, Hisar (29°10'N, 75°46'E and altitude of m .). The experiment was laid out in split plot design with four replications. | Heat use efficiency of Indian mustard Brassica juncea at different phenophases in Western Haryana India