water use, y ield and yield component of wheat under irrigation and nitrogen application in terrace soil of Bangladesh

Abstract

Abstract : A field experiment was conducted on Shallow Red Brown Terrace soil of Madhupur tract of Bangladesh in the rabi season (October to March) of 1997-98 to find out the optimum scheduling of irrigation and nitrogen (N) requirement for maximum yield of wheat (cv. Protiva) and water use of wheat. The experiment comprised of five levels of irrigation (I0-no irrigation, lrone irrigation at CRI; l2-two irrigation, one at CRI and another at booting; I3-two irrigation, one at CRI and another at early grain filling; L-three irrigation, at CRI, booting and early grain filling stage) and four rates of nitrogen (0, 80, 120 and 160 kg ha'1). A positive interaction between irrigation water and nitrogen rates on grain yield of wheat was observed. The treatment having three irrigation with N applicaton at the rate of 120 kg/ha gave the highest yield of 4.94 t/ha by using 206 mm of water was considered to be the optimum levels of irrigation and N in this soil. The grain yield under both irrigated and non- irrigated condition was increased by increasing rate of N up to 120 kg/ha. The yield was increased under higher irrigation level may be due to increased number of grains/spike and 1000 grain weight. On the other hand, the yield increase under higher N rate was attributed from increased spikes/m2 and grains/spike. Water use efficiency (WUE) of wheat was gradually decreased with the increasing irrigation level but it was increased with the increasing N rate up to 120 kg/ha.