Evaluation of the Effects of Cow Dung and NPK Fertilizer on Maize Plant (Zea mays) Grown on a Copper-Contaminated Soil

Greenhouse experiments were conducted to determine the effects of cow dung and NPK fertilizer on copper toxicity to maize grown in a copper-contaminated soil. NPK fertilizer treatments had the highest shoot phyto-toxicity of B - 100%, C - 94.3% and D - 83.6%/.A similar result was observed for root phyto-toxicity. On the other hand, cow dung treatments significantly reduced (P ≤ 1%) the effect of copper toxicity on the maize plant as evidenced by the negative values of shoot phyto-toxicity (E,- 11.0%, F,- 6.0%). Maize plants also showed significant reduction of growth at all NPK fertilizer treatments, relative to the cow dung treatments as measured by shoot and root dry weights. However, the various fertilizer treatments did not have any significant effect on the uptake to copper by the maize plants.Keywords: Cow dung, NPK, maize, copper