RESPONSE OF COWDUNG AND UREA ON TWO BORO RICE VARIETIES UNDER WETLAND CULTIVATION

Abstract

A field experiment was conducted to evaluate the response of Cowdung and Urea on rice under wetland condition at the research farm of Sher–e–Bangla Agricultural University, Dhaka, Bangladesh during the Boro season (Mid November–March) of 2012–13. Two rice varieties namely BRRI dhan29 (V1) and Heera 4 (V2) and seven treatments including control viz. T0: controlled or no fertilizer, T1: 0 t ha–1 Cowdung (0% N) + 280 kg ha–1 Urea (100 % N as Urea), T2 = 1.28 t ha–1 Cowdung (10% N as CD) + 252 kg ha–1 Urea (90%N as Urea), T3 = 2.56 t ha–1 Cowdung (20% N as CD) + 224 kg ha–1 Urea (80%N as Urea), T4 = 3.84 t ha–1 Cowdung (30% N as CD) + 196 kg ha–1 Urea (70%N as Urea), T5 = 5.12 t ha–1 Cowdung (40 % N as CD) + 168 kg ha–1 Urea (60%N as Urea) and T6 = 6.40 t ha–1 Cowdung (50 % N as CD) + 140 kg ha–1 Urea (50%N as Urea) were used for the present study. The experiment was laid out in RCBD method with three replications and analysis was done by the MSTAT–C package program and means were adjudged by DMRT at 5% level of probability. Effect of variety was significantly affected the whole characters of the study except harvest index and K content in postharvest soil where the HYV variety Heera 4 had highly significant than BRRI dhan29. Similarly, whole studied traits of the study were also influenced significantly due to the effect of cowdung + Urea as a source of N where the treatment T4 (3.84 t ha–1 cowdung + 196.0 kg ha–1 Urea) showed understanding superiority for getting the better growth, higher yield and greater significant effect on nutrient management practices. Most of the studied traits were also influenced significantly due to the effect of interaction of variety and cowdung + Urea fertilizer where harvest index, P and K content in grain and N and P content in straw showed numerically similar performance among the interaction treatments due to non significant variation. Rest of the characters had highest in variety Heera 4 receiving of 3.84 ton cowdung ha–1 + 196.0 kg Urea ha–1 (V2T4) as well as the tallest plant (101.40 cm), more effective tillers hill–1 (23.90), longest panicle (33.14 cm), more grains panicle–1 (219.30), highest 1000–grain weight (33.10 g), highest yield of grain, straw and biological (6.53, 7.96 and 14.49 t ha–1) were recorded. Only N content in grain had highest (1.190%) in Heera 4 receiving of 5.12 ton cowdung ha–1 + 168.0 kg Urea ha–1 (V2T5) while K content in straw had highest (1.475%) in Heera 4 treated by T4 (V2T4). NPK uptake in grain (75.38, 21.73 and 20.97 kg ha–1, respectively) and straw (59.28, 14.66 and 117.50 kg ha–1, respectively) were found in V2T4 while same treatment also recorded the highest NPK content in postharvest soil (0.0960 ppm, 34.70 ppm and 0.0467 meq 100 g–1, respectively). The overall results indicate that the variety Heera 4 and 3.84 ton cowdung ha–1 (30%) along with 196.0 kg Urea ha–1 (70%) as singly or their interaction was the most selective variety and optimum Nitrogen levels for getting the superior yield under wetland condition and higher capability to increase nutrient ability in grain and straw as well as increase the sustenance capacity of the soil. The above results also indicated that the organic fertilizer as cowdung can be reduced 30% use of inorganic fertilizer which also reduced the soil pollution by chemical fertilizer.