EFFECT OF FOLIAR APPLICATION OF POTASSIUM AND GA3 ON GROWTH AND YIELD PERFORMANCE OF WHEAT UNDER DROUGHT CONDITION

Abstract

To investigate the protective effect of additional foliar application of potassium and gibberellic acid on wheat under non-irrigated water stress an experiment was conducted at the research field of Crop Physiology and Ecology Department, Hajee Mohammad Danesh Science and Technology University, Dinajpur during the period of November 2018 to March 2019. The experiment was laid out in a split plot design with three replications. Four growing conditions (well water, water stress, foliar application of 2.23% K2SO4 under water stress and foliar application of 300 ppm GA3 under water stress) were set up as the main plot treatment and two wheat varieties (Kanchan and BARI Gom 30) were set up as sub plot treatment. Interaction effect of growing conditions and wheat varieties significantly influenced the different physiological traits, yield and yield attributes of wheat. Maximum relative water content of flag leaf, chlorophyll content of flag leaf, canopy temperature depression, number of spikes m-2 , plant height, spike length, number of spikes plant-1 , number of spikelets spike-1 , number of grains spike-1 , grain weight spike-1 , 500-grain weight, above ground biological yield, grain yield and minimum proline content of flag leaf were observed under well water condition. Non-irrigated water stress significantly reduced different physiological traits, yield and yield attributes except proline content of flag leaf of wheat, whereas foliar application of potassium and GA3 improved these traits under water stress condition. But foliar application of potassium was found more effective and BARI Gom 30 respond better in these respects. Foliar application of potassium improved biological yield (22.04% and 15.16%) and grain yield (3.19% and 2.59%) in Kanchan and BARI Gom 30, respectively, whereas foliar application of GA3 improved biological yield (12.12% and 17.00%) and grain yield (1.47% and 1.18%) in Kanchan and BARI Gom 30, respectively under nonirrigated water stress condition. From the overall results it can be concluded that foliar application of potassium and GA3 could improve grain yield of wheat under non-irrigated water stress condition and additional foliar application of potassium along with recommended potassium was more effective.