This study examined to evaluate the nitrogen use efficiency (NUE) of neem-coated urea (NCU), nano urea (NU) and productivity of two widely grown rice varieties, ASD16 and ADT46 around Tamirabarani River basin. Treatments included varying foliar dosages of NCU, NU, the recommended dose of fertilizers (RDF) and control. Results showed RDF significantly outperformed all treatments in quantitative parameters (plant height, tiller density, grain yield, straw yield) and qualitative parameters (chlorophyll content, leaf area index), followed by NCU, NU and the control. The balanced nutrient profile of RDF and soil-based application maximized uptake and plant growth, unlike the nitrogen-limited and foliar-dependent NCU and NU. Notably, NCU’s higher nitrogen content (46 %) and slow-release properties via neem coating enhanced absorption compared to NU’s lower nitrogen (4 %) and reliance on foliar uptake, which likely faced inefficiencies due to leaf surface limitations and environmental factors like humidity. These findings position RDF as the most effective option for optimizing rice productivity in this region, highlighting the critical role of comprehensive nutrient delivery and efficient absorption mechanisms.
Dheenadhayalan et al. (Wed,) studied this question.