QUANTIFYING THE PERFORMANCE OF UREA DEEP PLACEMENT APPLICATORS IN BORO RICE CULTIVATION

Abstract

A research work was carried out at the Research Farm, Sher-e-Bangla Agricultural University, Dhaka during the period from December 2015 to April 2016 in order to determine the suitable urea deep placement applicator and observing the growth performance with a view to increase the grain yield of boro rice. The experiment consisted of one factors. Factor: T 0 = Control plot, T = Application of urea briquette by hand placement, T 2 1 = Application of urea briquette by battery- powered applicator, T = Application of urea briquette by BRRI applicator, T = Application of urea briquette by injector applicator, T 5 4 = Application of urea briquette by push- type applicator, T = Application of prilled urea by broadcast method. The experiment was set up following randomized complete block design with three replications. Experimental results showed that nitrogen sources and application methods had significant effect on plant height, effective tiller no/ hill, grain yield, straw yield, biological yield and harvest index. The application of T treatment showed the highest grain yield (5.82 t /ha) and straw yield (7.28 t/ha) than any other sources of nitrogen and methods of application. Experimental results showed that nitrogen sources and application methods had significant effect on NH 4 + 3

concentration in standing water of experimental paddy soil. The higher ammonium concentrations (9.17 ppm) were found in the water of T (Application of prilled urea by broadcast method) treatment during 1-7 days of water samples. The soil ammonium concentrations were significantly affected by nitrogen sources and application methods. The higher soil ammonium concentrations (120.3 mg/kg dry soil) were observed in the treatment of T 3 6 (Application of urea briquette by BRRI applicator) during 1-7 days of collected soil samples. Findings revealed that when urea briquette was placed with BRRI applicator showed the superiority over other sources of nitrogen and application methods to produce higher grain yield of boro rice.