Enhancing NPK Uptake and Economic Efficiency of Hybrid Maize by Site-Specific Nutrient Management on Undeposited Alluvial Soil in An Phu, An Giang

Abstract

    The objectives of this study were to determine (i) the efficiency of NPK fertilizers application by site-specific nutrient management (SSNM) on NPK uptake and (ii) the economic efficiency of SSNM for maize on undeposited alluvial soil. The on-farm research was conducted in a completely randomized block design with three farmers’ fields, with three replications in 2014 - 2015 dry season in An Phu - An Giang. The treatments included (i) SSNM (200 N - 90 P₂O₅ - 80 K₂O), (ii) bio-organic fertilizer incoporation with NPK fertilizers application - BOF + NPK (bio-organic fertilizer contains 15% organic matter; the concentration of N – P₂O₅ – K₂O is 1,0 - 1,0 - 1,0 (%), respectively). The density of nitrogen-fixing and phosphorus-solibilizing was 1 x 10⁶ CFU per gram and chemical NPK fertilizers of 138 N - 63 P₂O₅ - 56 K₂O), and (iii) farmers’ practice - FP (236 N - 126 P₂O₅ - 46 K₂O). The results showed that, compared to FP, the SSNM application gave better grain yield, NPK uptake as well as higher net benefit.