Integration of Organic and Inorganic Nutrient Sources on the Yield and Economics of NERICA 4 and Toyohatamochi Upland Rice Varieties

Abstract

Rice yield in sub-Saharan Africa is still low in contrast to other parts of the globe, and this is mainly attributed to low soil fertility and poor cultivation techniques. The cost of chemical fertilizers is prohibitively high for small- holder farmers in the region. On the other hand, however, organic fertilizer sources like cow dung and chicken waste are freely and readily available to improve soil properties and nutrients for improved plant growth and grain quality. To evaluate the efficiency of organic fertilizer in combination with chemical fertilizer for improved upland rice yield, a field experiment was con- ducted with two factors: fertilizer (O30, 30% Organic and 70% Chemical; O50, 50% Organic and 50% Chemical; and C, Control having chemical fertilizer only) and variety (NERICA 4 and Toyohatamochi). Results showed that the percent- age of ripened grains in the 50% organic treatment was significantly higher than in the 30% organic treatment and Control. Additionally, NERICA 4 exhibited a significantly higher percentage of ripened grains compared to Toyohatamochi. While there was no significant difference in rice yield between fertilizer levels and rice varieties, mean rice yield, ripen grain percentage and net benefit for the 50% organic treatment were the highest, followed by 30% organic, then Control. The cost-benefit analysis results showed that 50% organic fertilizer had the low- est cost of fertilizer input, and the highest net benefit.