Effect of split application of nitrogen fertilizer on yield traits and yield of high yielding aromatic rice varieties in Bangladesh

Abstract

A field experiment was conducted at Bangladesh Agricultural University, Mymensingh, Bangladesh during Aman season in 2013 to evaluate the effect of proper time of nitrogen application on yield and yield parameters of high yielding rice varieties. Two transplanted aromatic aman rice varieties (BRRI dhan37 and BRRI dhan38) and four timing of nitrogen fertilizer application (N 1 = ½ during final land preparation + ½ at 30 DAT, N 2 = 1 / 3 at 15 DAT + 1 / 3 at 30 DAT + 1 / 3 at 45 DAT, N 3 = 1 / 4 at 15 DAT + ½ at 30 DAT + 1 / 4 at 45 DAT and N 4 = 2 / 3 at 15 DAT + 1 / 3 at 45 DAT) were used in this experiment. The experiment was arranged in a randomized complete block design with three replications as factorial arrangement. All agronomic practices were applied as recommended for each cultivar. Yield and yield traits (plant height, total tillers, effective panicle, panicle length, grains per panicle, 1000-grain weight, grain yield, straw yield, harvest index) was measured. Results showed that the effect of nitrogen split application on plant height, total tillers, effective panicle, panicle length, grains per panicle, 1000-grain weight, grain yield and straw yield was significant. The results revealed that three equal splits of nitrogen (N 2 ) application ( 1 / 3 at 15 DAT + 1 / 3 at 30 DAT + 1 / 3 at 45 DAT) produced the highest grain yield (3.29 t ha -1 ) which was statistical differed from all N splits application treatments and the lowest grain yield (2.41 tha -1 ) was obtained from N 1 treatment which was statistically similar to N 4 treatment. The variety effect was significant on all traits except plant height, number of grains panicle -1 , number sterile spikelets panicle -1 and stubble yield. The variety BRRI dhan38 produced more grain yield than BRRI dhan37. The effect of nitrogen split application and variety (N×V) on total traits was significant and N 2 ×V 2 combination produced the highest grain yield among all the combinations.