Abstract

                             Potassium is one of the major nutritive element which will require greater attention in order to ensure grain yield and mitigation of biotic and abiotic stresses as well as improvement in quality of maize. The soils with high in calcium and or magnesium may require high levels of K for satisfactory nutrition of crops. The availability of K depends on concentration relative to that of Ca²⁺ and Mg²⁺ than on the total quantity of K present. To study the influence of potassium levels and its influence on growth, yield and nutrient uptake in maize, a pot culture experiment was carried out with graded levels of potassium (T₁ – control, T₂ – 40 kg K₂O ha^-1, T₃ – 80 kg K₂O ha^-1, T₄ -120 kg K₂O ha^-1) to study the influence of potassium on growth, yield and nutrient uptake of maize in calcareous soil. The results indicated that plant height showed significant response up to 40 kg K₂O ha^-1, whereas SPAD values and Leaf area index were higher up to 80 kg K₂O ha^-1 while the root parameters showed significant response up to 120 kg K₂O ha^-1.Yield parameters viz., cob length and 100 grain weight were significantly influenced up to 120 kg K₂O ha^-1. Whereas, cob girth and rows per cob responded only up to 80 kg K₂O ha^-1. Grain and stover yield of hybrid maize showed significant response up to 120 kg K₂O ha^-1. The total uptake of N, P and K showed significant response up to 120 kg ha^-1 in calcareous soil. Significant positive correlation occurs between growth, yield parameters, NPK uptake. Application of potassium up to 120 kg K₂O ha^-1 is necessary for the continuous supply of K to maize and to maintain K equilibrium in soil.

Key words : Grain yield, Hybrid Maize, Inceptisols, NPK Uptake, Potassium.