GROWTH AND YIELD OF T. AMAN RICE AS AFFECTED BY NITROGEN MANAGEMENT FROM DIFFERENT SOURCES

Abstract

A field experiment was conducted at SAU farm, Dhaka from August to November 2007 to find the effects of different sources and management of N on that growth and yield of T. aman rice (cv. BR 11). The soil was silt loam having p1-1 5.4, organic matter 1.75%, available P 8.0 gg g 1, available S 9.6 ig g' and K 0.11 meq/100g contents. There were nine treatments taking various doses of urea, USG and vermicompost viz. T o: control, T 1 : 120 kg N from urea, 12 : 100 kg N from urea+ 20 kg N from vermicompost, T 3 : 80 kg N from urea + 40 kg N from vermicompost, T4: 5 : 120 kg N from USG, T 6: 103.5 kg N from USG + 16.5 N from vermicompost, 1 60 kg N from urea + 60 kg N from vermicompost, T 7: 69 kg N from USG + 51 N from vermicompost and T 8 : 45 kg N from USG + 75 N from vermicompost. The treatments were laid out in a randomized complete block design with four replications. Recommended doses of P, K, S and Zn were applied to all plots. The application of urea, USG and vermicompost had a significant positive effect on the plant height, panicle length and grains panicle". The highest grain (4.85 t hi) and straw (6.92 t hi') yields of rice were recorded in the T treatment. The T o (control) treatment gave the lowest grain (2.56 t hi') and straw yields (3.97 t hi'). The application of urea, USG and vermicompost significantly increased the N, P. K and S contents as well as their uptake by the crop. Overall results indicate that the application of urea at a recommended rate i.e. 120 kg N hi' along with recommended rate of P. K, S and Zn is necessary for obtaining higher grain yield as well as straw yield of T. aman rice in SAU farm soil and also in the areas having similar climatic, land and soil characteristics.