Performance of wet direct-seeded rice (Oryza sativa L.) with different levels and sources of slow-release urea fertilizers

A field experiment was conducted to study the effect graded levels and sources of slow-release urea fertilizers on growth, yield, nitrogen use efficiency and economics of wet direct seeded rice in kharif, 2022. The results revealed that 100% recommended dose nitrogen at 120 kg ha-1 through silicon and cedar wood oil coated urea recorded highest drymatter production at all stages of crop i,e active tillering, panicle emergence, flowering and harvest respectively. Similar results of leaf area index, SPAD chlorophyll and green seeker readings were also found at 100% recommended dose of nitrogen through silicon and cedar wood oil coated urea at all stages of crop i,e active tillering, panicle emergence and flowering. The results revealed that 100% RDN (Recommended Dose of Nitrogen) (120 kg/ha) applied through silicon coated urea resulted in the highest grain yield (6183 kg/ha) and straw yield (7047 kg/ha) which ulimately fetched higher gross return of ₹. 1,37,933/ha, net returns ₹. 98,763 and benefit-cost ratio of 2.52. The data indicated that significantly higher agronomic nitrogen use efficiency (32.2 kg kg-1), partial factor productivity (51.5 kg kg-1) and utilization efficiency (43.0 kg kg-1) were recorded in treatment receiving 100% RDN through silicon coated urea. It can be concluded that RDN applied through silicon coated urea @ 120 kg/ha found to be a suitable alternative source to neem coated urea in increasing the grain yield and profitability.