Effects of Different Levels of Supplementary Nitrogen and Potassium in Nutrient Solution on Yield and Leaf N and K Concentrations of Tomato

The effects of different levels of nitrogen (100, 200, 300 and 400 mg/L) and potassium (125, 250 and 375 mg/L) on yield and leaf N and K concentrations of tomato were investigated in perlit culture using a factorial randomized design with three replications. The highest fruit yield was obtained with 200 mg/L N. Higher levels of nitrogen decreased tomato yield. With increasing nitrogen concentration in nutrient solution, N content of leaf increased significantly whereas leaf K concentration decreased. Different potassium levels had no significant effect on tomato yield. With increasing potassium levels of nutrient solution, concentration of leaf N decreased significantly whereas concentration of leaf K increased. The greatest and the least fruit yields were obtained from N200K250 and N400K375 treatments, respectively. The highest and the lowest concentrations of leaf N were observed in N400K125 and N100K375 treatments, respectively. The greatest and the least concentrations of leaf K were observed in N100K375 and N400K125 treatments, respectively.