ABSTRACT 

The experiment was conducted at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh during the period from January to June 2016 with a view to finding out the effect of integrated nutrient management on the performance of boro rice. The experiment comprised of two varieties namely BRRI dhan28, BRRI dhan29 and seven integrated nutrient management practices viz. BRRI recommended dose, 75% of BRRI recommended dose + 25% N from cowdung, 50% of BRRI recommended dose + 50% N from cowdung, 25% of BRRI recommended dose + 75% N from cowdung, 75% of BRRI recommended dose + 25% N from poultry manure, 50% of BRRI recommended dose + 50% N from poultry manure, 25% of BRRI recommended dose + 75% N from poultry manure. The experiment was laid out in a split plot design with three replications. Variety exerted significant influence on yield and plant characters of boro rice. BRRI dhan29 produced the higher plant height (88.28cm), panicle length (22.47cm), number of grains panicle-1 (120.54), grain yield (5.44 t ha-1), straw yield (5.92 t ha-1) and harvest index (47.80%) while BRRI dhan28 had the higher number of total tillers hill-1 (13.39) and weight of 1000-grain (25.00gm). The highest number of total tillers hill-1 (13.82.), length of panicle (22.34 cm), number of grains panicle-1 (122.74), weight of 1000-grains (24.57 g), grain yield (6.40 t ha-1) and harvest index (50.72%) were obtained at the treatment with 25% of BRRI recommended dose + 75% N from poultry manure. The highest plant height (89.78 cm), straw yields (10.89 t ha-1) were obtained from the treatment with 50% of BRRI recommended dose + 50% N from poultry manure. The interaction between varieties and integrated nutrient management showed significant effect on the studied characters. The highest number of total tillers hill-1 (15.47), weight of 1000-grain (25.07 g) were obtained from the interaction between variety BRRI dhan28 and 25% of BRRI recommended dose + 75% N from poultry manure. The highest number of grains panicle-1 (140.05), grain yield (6.47 t ha-1) and harvest index (50.91%) were obtained from the interaction of variety BRRI dhan29 with 25% of BRRI recommended dose + 75% N from poultry manure. The lowest number of total tillers hill-1 (9.31), grain yield (4.36 t ha-1), and harvest index (45.11%) were obtained from the interaction of the variety BRRI dhan29 with BRRI recommended dose of fertilizer. Key words: Nutrient management, BRRI dhan29, yield.

Introduction

Integrated nutrient management is imperative for crop production in a sustainable way. Among the available sources of N, cowdung and poultry manure are rich in N content. Cowdung is the commonly practices organic manure for crop cultivation in Bangladesh. The long term research reveals that addition of cowdung at the rate of 5 t ha-1 improved the rice productivity as well as prevented the soil resources from degradation (Bhuiyan, 1994). Poultry manure is also the most important considering factor. Approximately 75% of the total nitrogen in poultry manure are available for plant during the year of application. When poultry manure is applied with nitrogenous fertilizers, it helps to release the nutrient elements slowly during the period of crop growth. Application of urea in combination with cowdung may enhance the productivity of rice. So, integrated use of organic manures and inorganic fertilizers can contribute to increase in the N content of rice soil as well as to increase in long term productivity and enhancement of ecological sustainability. Experiment with urea N in combination with poultry manure and cowdung in rice found that application of manures and different doses of urea (N fertilizer) significantly increased the yield components and grain and straw yields (Rahman et al., 2009). Moreover, a suitable combination of variety and rate of fertilizer dose is necessary for better yield. Though rice is one of the most important crops of the world, enough information regarding the varieties of rice and their response to organic manure and nitrogen 103