Abstract

The performance of cocoyam (Colocasia esculenta L. Schott) to varying levels of cow dung and potassium fertilizer was investigated in 2012 and 2013 cropping seasons under field conditions at National Horticultural Research Institute (NIHORT), Imo State, Nigeria. The experiment was a 4 × 2 factorial arrangement in a randomized complete block design with three replications. The treatments were four levels of cow dung (0, 10, 20 and 30 t ha^-1) and potassium fertilizer (0, 20, 40 and 60 kg K₂O ha^-1). Application of cow dung at the highest rate of 30 t ha^-1 significantly (P < 0.05) enhanced plant height, number of leaves, leaf area index, number of suckers and yield of cocoyam (23.6 t ha^-1) in 2012 cropping season relative to the lower rates and the control. However, in 2013 cropping season, cow dung at the lower rate of 20 t ha^-1 gave optimum corm yield of 23.3 t ha^-1. In general, potassium fertilizer application did not exert much influence on growth and yield of cocoyam as significant effect was observed only in 2013 cropping season. Corm yield was significantly (P < 0.05) improved by the application of 60 kg K₂O ha^-1 (22.3 t ha^-1) in 2013 cropping season relative to the control. The results of this study have shown the effectiveness of cow dung in improving the productivity of cocoyam, thereby enhancing food security in Nigeria.

Key words: Colocasia esculenta, corm yield, cowdung, food security, potassium fertilizer, soil fertility.