Physiological Responses of Maize (Zea mays L.) to Copper (Cu) Induced Stress

Abstract

Z mays L. is among the most essential staple crops globally. It has multifunctional uses both as food; feed as well as for other industrial purposes. Pollution of soil by heavy metals is however a huge factor limiting the optimal growth of this crop. The purpose of this study was to investigate the physiological responses of maize when induced with copper (Cu) at five different concentrations (0%, 39%, 77%, 115% and 154%) respectively. The plant material was acquired from Agricultural Development Program, Rumuodumaya, Port Harcourt while soil was sterilized and analyzed using standard protocols. Planting was done under controlled environment. After 1 week of planting, growth parameters such as Plant height, number of leaves, Leaf length and leaf area were recorded at weekly interval for 9 weeks. The study revealed that growth responses of the maize studied decreased as the concentration increased for copper (Cu).  Higher treatments at 115% and 154% resulted in mortality of the maize at week three. There were conditions where growth performances fluctuated with variation in the treatments and there was also reduction in chlorophyll content as the concentration increases. It is therefore suggested that high concentration of heavy metal is detrimental to the growth of maize plant and the level of negative effect relies on the span of exposure.