Impact of crop and nutrient management on crop growth and yield, nutrient uptake and content in rice

Abstract

System of rice intensification (SRI) together with appropriate nutrient management holds promise in increasing rice productivity with micronutrient enriched grains. Trials were conducted to investigate the performance of SRI vis-à-vis conventional management practices (CMP), both with either integrated nutrient management (INM) or organic sources of nutrients. Grain yields were consistently higher under SRI (34.6%) than with CMP under the same nutrient management system. At the same time, yields under INM were higher than for those with organic fertilization. There were significant differences among treatment combinations also; both SRI–INM and SRI–organic out-yielded CMP–INM and CMP–organic, respectively, by 43.8 and 24.8%. Further, SRI with organic sources produced 18.6% higher grain yield than CMP with INM, which showed a way to achieve higher output of rice grain grown organically. Significant improvements were observed with SRI in root growth, xylem exudation rate, LAI, canopy light interception, SPAD chlorophyll level, photosynthesis rate, and grain-filling rate. The improvements in physiological functioning evidently contributed to better grain formation and yield under SRI management. Both the rice grains and straw obtained with SRI methods contained more N, P, K, Fe, Mn, Cu, and Zn than grains and straw produced with CMP. SRI methods not only raised rice productivity, but also enhanced nutrient uptake due to greater root growth and activity, and improved the nutritional content and quality of produced grain.