Efficiency of Different Doses of Potassium on Yield of Rice Under Different Establishment Methods

Abstract

Abstract Disproportionate use of fertilizer in various systems of rice establishment amidst poor knowledge of nutrient use and availability under different soil and environmental condition had added further challenges to rice production. Among the substantial loss of major macronutrients from the rice field, potassium stands after nitrogen. The traditional approach of applying potassium fertilizer only at the initial growth stages has confined their availability during the crucial stage of flowering and grain filling. However, the application of potassium fertilizer on a split basis, meaning applying them at multiple growth stages throughout the growing season, could increase the nutrient availability leading to uniform grain filling during the reproductive stage resulting in higher yields and reduced sterility. Thus to track down the impacts of potassium split application on patterns of growth and yield of rice, a field experiment was conducted by plying different establishment methods and the varied amount and methods of potassium application. The experiment was conducted in a split-plot design with four replication in the sub-tropical climate of the inner terai of Nepal. The main plot treatment consisted of two establishment methods namely, direct seed rice (DSR) and transplanted rice (TPR) while sub-plot treatment consisted of seven potassium management practices i.e. potassium omission, 30kg K ha− 1 basal dose, 30kg K ha− 1 with two splits (15 kg K ha− 1as basal and 15 kg K ha− 1 at PI stage), 60kg K ha− 1 basal, 60kg K ha− 1 with two splits(30 kg K ha− 1as basal and 30 kg K ha− 1 at PI stage), 90kg K ha− 1 basal and 90kg K ha− 1 with two splits(45 kg K ha− 1as basal and 45 kg K ha− 1 at PI stage). The research revealed that grain yield was not significantly influenced by establishment methods but the straw yield was significantly influenced. Comparatively high grain yield was obtained in TPR (3.88 t ha− 1) compared to DSR (3.73 t ha− 1). Potassium applied at 60kg K ha− 1 with two splits resulted in a significantly higher (P < 0.05) yield (4.21t ha− 1). The overall analysis revealed that potassium applied at 60kg K ha− 1 and 90kg K ha− 1 with two splits under TPR resulted in high grain yield. The findings suggest that rice yield could be obtained through an efficient supply of potassium in splits at different crucial growth stages reducing sterility and enhancing rice growth.