Effect of spacing of transplanting, rate and depth of placement of urea super granules (USG) on the yield of BORO rice

Abstract

An experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University, Mymensingh during December 2008 to May 2009 in order to evaluate the effect of spacing of transplanting, rate of urea super granules (USG) and depth of their placement on the yield of Boro rice. The experiment consisted to two spacing of transplanting, three rates of USG and three depths of placement of USG were considered. Experiment was laid out in a randomized complete block design with three replications. Our results revealed that the effect of spacing of transplanting was significant in respect of yield and most of the plant characters. The higher grain yield (4.46 t/ha) was obtained from 20cm × 20cm spacing of transplanting than 20cm × 25cm spacing of transplanting (4.24 t/ha). Effect of rates of USG significantly influenced all the yield contributing characters except weight of 1000-grain and crop characters length of panicle. The highest grain yield (4.73 t/ha) was obtained at 2.7g USG (68 kg N/ha). Effect of depth of placement of USG significantly influenced the yield, yield attributes and growth characters of the crop except length of panicle and weight of 1000-grain. The highest grain yield (5.08 t/ha) was obtained when the crop was grown with 8 cm depth of placement of USG. USG placement at a depth of 6 cm gave the lowest grain yield (3.73 t/ha). From the interaction of spacing of transplanting and rate of USG, the highest grain yield (4.82 t/ha) was obtained from 20cm × 20cm spacing of transplanting × 68 kg N/ha and the lowest grain yield (3.75 t/ha) was obtained from 20cm × 25cm spacing of transplanting × 1.8g USG (46 kg N/ha). From the interaction of effect of spacing of transplanting and depth, the highest grain yield (5.30 t/ha) was obtained from 20cm × 20cm spacing of transplanting × 8 cm depth and the lowest grain yield (3.68 t/ha) from 20cm × 20cm spacing of transplanting × 6 cm depth. From the interaction of rate of USG and depth, the highest grain yield (5.27 t/ha) was obtained from the interaction of 2.7g USG (68 kg N/ha) × 8 cm depth and the lowest grain yield (3.21 t/ha) was also obtained from 1.8g USG (46 kg N/ha) × 6 cm depth. From the interaction of spacing of transplanting, rate of USG and depth, the highest grain yield (5.39 t/ha) was obtained from 20cm × 20cm spacing of transplanting × 2.7g USG (68 kg N/ha) × 8 cm depth and the lowest grain yield (3.19 t/ha) was also obtained from 20cm × 20cm spacing of transplanting × 1.8g USG (46 kg N/ha) × 6 cm depth. It may be concluded that BRRI dhan29 with spacing of transplanting of 20cm × 20cm in combination with 2.7g USG (68 kg N/ha) and 8 cm depth of its placement appeared as the promising practice to maximize the yield of boro rice.