NPK Compound Fertilizer Foliar Application Impacts Productivity and Grain Quality of Rice

A field experiment was conducted during the 2018 and 2019 rice growing seasons at The Experimental Farm of Rice Research and Training Center, Sakha, Kafrelsheikh, Egypt, to study the effect of foliar application of NPK (20:20:20) or urea combined with different nitrogen levels on grain yield and quality of Sakha 109 rice variety. Urea (46.5% N) and complex paste water-soluble NPK fertilizer (20:20:20) were used as the nutrient sources for the experimental treatments. For foliar application, NPK was used at the rate of 2 gm per liter of water and nitrogen used was at the concentration of 2% as urea. The field experiments were laid out in a Randomized Complete Block Design with four replications. The studied characteristics were chlorophyll content (SPAD value) at 55 days after transplanting, plant height at harvest, number of panicles per hill, panicle length, panicle weight, number of filled grains per panicle, unfilled grains percentage, 1000-grain weight, grain yield, straw yield and grain quality characteristics (hulling, milling and head rice percentages). N and K uptake (kg ha-1) were also determined. All studied characteristics were significantly influenced by the foliar fertilizer application in the two seasons. Application of NPK or N alone twice might improve rice grain yield and quality. The economic feasibility indicated that the application of 123.75 kg N ha-1 combined with foliar application of NPK or 2% nitrogen twice recorded the highest values of gross return and net return as well as a benefit-cost ratio.