Nickel toxicity: Effects on growth and metabolism of maize

Abstract

Effects of graded concentrations of nickel on maize (Zea mays L.) growth and certain metabolic parameters were studied. Under nickel (Ni) stress conditions, leaves become chlorotic at low concentrations and necrotic at, relatively, high ones. Concerning its effect on plant growth, nickel reduces dry matter production, more significantly in root system which accumulates large amounts of Ni. In leaves, chlorophyll content was severely decreased. Furthermore, this metal induces leaf accumulation of soluble phenolics, starch and reducing sugars. The accumulation of carbohydrates in shoots might be, at least in part, the cause of root growth inhibition.