RESPONSE OF UREA SUPERGRANULE AND PRILLED UREA ON GROWTH AND YIELD OF BORO RICE

Abstract

A research work was carried out at the Research Farm, Sher-e-Bangla Agricultural University, Dhaka during the period from December 2012 to May 2013 in order to determine the suitable nitrogen source to observe the growth performance with a view to increasing the grain yield of boro rice. The experiment consisted of two factors. Factor A: Nitrogen Sources (5 levels); To: No nitrogen (control). T 1 : Recommended dose of USG. 12: 150 KgNhi' as USC. 1 3 : Recommended dose of prilled urea and l.: 150 KgNha" as prilled urea, and factor B: Variety (4 levels): V 1 : BRRI dhan29, V2: BRRI hybriddhan2, V 3: BRRI dhan58 and V 4 : Heera 4. The experiment was set up following split-plot design with three replications. Experimental results showed that nitrogen sources had significant effect on plant height. tillers hiil* effective tillers hilY'. non-effective tillers hilr', grains panicl&', unfilled grains panicle", grain yield, straw yield, biological yield and harvest index. The application of T 2 treatment showed the highest grain yield (7.96 t ha") and straw yield (9.50 t ha1 ) than any other sources of nitrogen treatments. All the studied characters except harvest index varied significantly due to varieties. BRRI dhan29 gave the higher grain yield (7.15 t hi') than Heera 4 (6.83 t haj, BRRI hybriddhan2 (6.75 t hi) and BRRI dhan58 (6.50 hi') which is mainly attributable to the highest number of grains panicl&' (102.71). treatment and BRRI dhan29 had the higher performance in terms of producing the highest grain yield (8.46 it hi) and straw yield (9.94 t hi') The combination of the 12 among the interaction effects. The N, P and K uptake both in grain and straw of boro rice increased significantly due to application of nitrogen fertilizer. The highest total N. P and K uptake 145.29 kg ha4 . 33.14 kg hi' and 17.24 kg hi'. respectively was observed in 12 treatment. The mean apparent recovery of N by tested varieties was obtained (77.54%) with the application of T2 treatment, but the nitrogen use efficiency was highest (33.20 kg grain kg' N applied) in 1, treatment. Findings revealed that application of 150 KgNha" as USC showed the superiority over other sources of nitrogen to produce higher grain yield of boro rice. Interaction treatment of T 2V, i.e. application of 150 KgNha 4 as USC with BRRI dhan29 performed best and interaction of T2 treatment with other tested varieties were also promising in producing higher yield.