Assessment of crop growth, soil properties and crop yield in an upland acidic soil with inorganic fertilizer blended with organic amendments in summer rice cropping seasons

Purpose Intensification of rice cultivation to meet the growing demand has imbalanced the nitrogen level in soil. Amendments of inorganic fertilizers increase yield, but at the same time affects the environment. Hence, different amendments are to be investigated which acting sustainably on soil and the environment upholds yield gains. Methods A study was carried out on acidic sandy loam soil in the irrigated summer seasons of the years of 2015-2016 and 2016-2017 to examine the effects of various amendments on rice growth, soil health and yield. The applied amendments were inorganic fertilizer blended with crop residues, farm yard manure and compost made of daily household green wastes. Results The highest yield of 53.33 +/- 2.09 Q/ha was recorded with application of inorganic fertilizer blended with compost and the lowest yield of 32.71 +/- 3.09 Q/ha without amendment. Strong positive correlations were found between soil moisture and volumetric water content (0.982 at p< 0.001), manganese and copper (0.900 at p< 0.001), whereas available phosphorus and manganese showed a strong negative correlation (- 0.901 at p< 0.001). Performing stepwise regression analysis, yield was found affected mostly by soil moisture and total carbon out of evaluated 17 soil traits. Conclusion The inorganic fertilization blended with the compost increased rice yield by 13.61% over inorganic fertilizer but a higher yield associated with compost demoted total nitrogen contents in soil, leading to lower soil nitrogen fertility and providing a negative feedback to sustainable agriculture. More research is required on compost development and application in different rice agroecosystems.