Impacts of different nitrogen forms and doses on agronomic performance of BRRI dhan29

Abstract

Nitrogen (N) is one of the most important nutrients for rice cultivation and probably the hardest to maintain in soil. This experiment was conducted to investigate the impacts of different N forms and doses as urea on BRRI dhan29 during boro season in Meherpur district, Bangladesh. The two most abundant forms of urea namely granular urea (GU) and urea super granule (USG) were selected with five doses (0, 100, 150, 200, and 250 kg ha-1) for each form. The treatments were replicated thrice in Randomized Complete Block Design (RCBD). GU was broadcasted and USG was applied using deep placement method. Other fertilizers viz. triple super phosphate, muriate of potash, gypsum, and zinc sulfate were applied at 100, 70, 60, and 5 kg ha-1, respectively. Agronomic parameters were measured by randomly selecting five hills from each plot. Application of N through USG significantly improved almost all agronomic characteristics such as plant height, total and effective tiller hill-1, panicle length, total and filled grains panicle-1, straw and biological yields, grain yield, and harvest index. BRRI dhan29 produced the highest grain and straw yields with the highest dose of USG application (250 kg ha-1). The 1000-seed weight was not significantly affected by N doses or by forms that might be due to its genetically controlled trait and environmental influence during the grain filling stage. Deep placement of USG ensured adequate N supply for a longer period that resulted in enhancement of growth and yield components of BRRI dhan29.