Effect of K on growth, yield, fruit quality and leaf nutrient status of apple Starking Delicious

Different K levels did not influence the trunk girth and tree volume significantly, whereas yield increased significantly with increase in K levels from 400 to 700 g K₂O/tree and was at par with 800 g K₂O/tree. Fruit colour, TSS contents and fruit weight increased significantly with increase in K levels from 400 to 700 g K₂O/tree. However, non-significant difference was observed in fruit firmness. Leaf K and Fe concentrations increased and N, P, Ca, Mg, Zn, Mn and Cu concentrations decreased with increase in K levels from 400 to 1,000 g K₂O/tree.