Direct
and Residual Effects of Applied Organic Manure on Yields in a Rice-Wheat
Cropping Pattern
M. BODRUZZAMAN[1],
M. A. SADAT[2], C. A.
MEISNER[3],
A. B. S. HOSSAIN[4], AND
H. H. KHAN[5]
Integrated use of chemical fertilizers with organic manures enhances the productivity and sustainability of agriculture systems especially for soils low in organic matter. A 3-year study with a rice-wheat cropping pattern was conducted on an acid, sandy loam soil at the Wheat Research Centre, Nashipur, Bangladesh to investigate the direct and residual effects of organic manures applied in combination with chemical fertilizers on crop productivity and soil fertility. The experiment was comprised of nine treatments in a randomized complete block design. The treatments were 1) absolute control (no fertilizers, no manures), 2) 100%NPKSZn, 3) 75%NPKSZn, 4) 75%NPKSZn+FYM (farm yard manure) applied in wheat (direct effect for wheat and residual effect for rice), 5) 75%NPKSZn+FYM applied in both wheat and rice (renewed effect), 6) 75%NPKSZn+FYM applied in rice (direct effect for rice and residual for wheat), 7) 75%NPKSZn+PM (poultry manure) applied in wheat (direct for wheat and residual for rice), 8) 75%NPKSZn+PM applied in both wheat and rice (renewed effect), 9) 75%NPKSZn+PM applied in rice (direct effect for rice and residual for wheat). Wheat yields from poultry manure (PM) plus 75% of the recommended NPKSZn ranged from 3.8 to 4.7 tha-1. In the first year these wheat yields were similar to the 100% recommended mineral fertilizer NPKSZn treatment and all other OM applied treatments. However, in the next two years, continued application of PM plus 75% mineral fertilizer produced wheat yields that were significantly higher than all other treatments. Plots with farmyard manure (FYM) plus 75% NPKSZn produced equivalent yields as plots applied with 100% NPKSZn indicating that FYM can substitute for 25% of the inorganic fertilizers. Rice yields were also significantly higher in plots where PM plus 75%NPKSZn compared to all other treatments. The results indicated that both PM and FYM had direct and residual effects on crop yields and plots where PM was applied gave greater yields overall than plots with FYM treatments. Soil analyses indicated that the pH was unchanged in all treatments over the 3-year period. Percent organic matter was reduced from 13 to 19% in plots where only inorganic fertilizer was used, and increased from 7 to 39% in plots where organic manures were applied, with the increasing trends more prominent in plots with PM than plots with FYM. Percent total N was unchanged in treatments where organic manures were combined with inorganic fertilizers, but was reduced in control plots and in plots where only inorganic fertilizers were used. The available soil P content increased dramatically in plots where PM was applied.
Key words: Wheat rice organic farm yard manure
[1] Wheat Research Centre, Bangladesh Agriculture Research Institute, Dinajpur Bangladesh
[2] Wheat Research Centre, Bangladesh Agriculture Research Institute, Dinajpur Bangladesh
[3] CIMMYT P.O. Box 6057 Gulshan Dhaka-1212 Bangladesh
[4] Wheat Research Centre, Bangladesh Agriculture Research Institute, Dinajpur Bangladesh
[5] Wheat
Research Centre, Bangladesh Agriculture Research Institute, Dinajpur Bangladesh