Comparison of Different Fertilizer Management Practices on Rice Growth and Yield in the Ashanti Region of Ghana

Abstract

Nutrient management is critical in increasing and sustaining rice yield. A field experiment was conducted to examine the effects of inorganic fertilizer (IF), poultry manure (PM) and their combinations on rice yield and possible residual effects. A randomized complete block design with three replications was used and the trial was conducted on a Gleysol. In 2011 SPAD values for IF and PM/ IF combinations (except 2.0 t/ha PM + 22.5-15-15 kg N: P2O5: K2O/ha) were significantly higher in the sixth week onwards than PM. Number of panicles/plant and number of panicles m2 were significantly higher for 90-60-60 kg N: P2O5: K2O/ha and 2.0 t/ha PM + 22.5-15-15 kg N: P2O5: K2O/ha than 6.0 and 4.0 t/ha PM resulting in significantly higher grain yield. Grain yield of IF was similar to grain yield of PM/IF combinations. In 2012 the residual effects showed a significantly higher SPAD value for the 6.0 t/ha PM. Also 6.0 t/ha PM, 4.0 t/ha PM and 4.0 t/ha PM + 30 kg N/ha had significantly high number of panicles/plant and number of panicles/m2 than IF. Residual effect of PM applied at 4.0 t/ha and above gave significantly higher grain yield than IF. Mean grain yield for the three years showed that 4.0 t/ha PM + 30 kg N/ha and 2.0 t/ha PM + 22.5-15-15 kg N: P2O5: K2O/ha gave significantly higher yields than the other treatments. The results indicate that integrating IF and PM is a better option in increasing and sustaining rice production.