Nutrient requirement and use efficiency of rice (Oryza sativa L.) as influenced by graded levels of customized fertilizer

Abstract

Balanced nutrient application is an important concern to minimize fertilizer use in crop culture. Field experiments were conducted during kharif 2017 and 2018 to find out the best level of NPK fertilizer for rice with two varieties of rice of same duration (130-135 days). Three grades of customized fertilizers (250, 350 and 450 kg ha−1) along with 100% RDF (Recommended dose of fertilizer) and absolute control constituted the treatment variables. The results revealed that the grades of customized fertilizer (CF) influenced the yield and uptake of nutrients. Application of CF @ 450 kg ha−1 was found to be significantly superior over absolute control and 100% RDF with respect to yield and uptake of nutrients, and found on par with all other grades of CF (250 and 350 kg ha−1). Applying 250 kg ha−1 of CF recorded higher agronomic efficiency (AE), apparent recovery efficiency (ARE) and partial factor productivity (PFP) for phosphorus (P) and potassium (K) but higher AEn, AREn and PFPn in 450 kg ha−1 of CF. The higher utilization efficiency of nitrogen (UEn) of 43.05%, phosphorus (UEp) of 181.88% and potassium (UEk) of 34.40% were recorded in 250 kg ha−1 of CF. The CF @ 450 kg ha−1 recorded higher nitrogen and phosphorus requirement (NR and PR) i.e., 2.65 and 0.61 kg’s, respectively. Whereas, potassium requirement (KR) was higher in 100% RDF. Higher response yard stick (RYS) of 5.33 was recorded in 250 kg ha−1 of CF compared to other grades of CF, 100% RDF and absolute control.