Increasing Zn ratio in a compound foliar NPK fertilizer in relation to growth, yield and quality of corn plant

Abstract

Corn plants are high nutrient demanding crop but sensitive to zinc (Zn) deficiency in soil. Application of Zn fertilizers could be a viable option to fulfill the crop demand for Zn and also to increase its content in grains. The objective of this study was to study the effect of foliar zinc applications on growth, mineral content and yield of corn plants under field conditions in 2013as well as its quality. Actual yields of maize harvested by farmers are at level much below attainable yield potential of currently cultivated varieties. Among many growth factors zinc was recognized as one of the limiting factors of corn growth and yielding. Corn plants cultivar Giza10 were sprayed with zinc solution at three concentrations (0.0, 1.0, 1.5 and 2 % Zn solution) or foliar application (0.0, 1.0, 1.5 and 2 % Zn) alone or in combination with NPK fertilizer. Results showed that maize with combined application of Zn (1.5%) and NPK fertilizer significantly improved plant height, 1000-grain weight, yield, grain yield and harvest index as compared to the treatment fertilized only with NPK. Zinc increased N, P and K uptake and grain yield of maize plants. Foliar-applied Zn compounds are effective for increasing Zn, Cu and Fe uptake in corn. The optimal rate of zinc foliar spray for achieving significant grain yield response ranged from 1.0 to 1.5 kg Zn/ha as compared to the treatment fertilized only with NPK.  Zinc treatment increased N, P and K uptake and grain yield.