Piotr Chohura¹, Andrzej Komosa², Eugeniusz Kołota³

Abstract. Dynamics of macroelement contents in the leaves of greenhouse tomato cv. Cunero F₁ grown in rockwool by the nutrient solution pH from 4.50 to 6.50 was studied. It was found, that content of nitrogen increased at the period June-July and decreased July-August. The nutrient solution at pH 4.50-5.50 enhanced but 6.00-6.50 reduced nitrogen content in the leaves. Potassium content increased in the whole vegetation period, and the effect of nutrient solution pH was different in a given year of study. In the opposition to potassium, calcium contents decreased during plants growing. Higher levels of calcium in the leaves were related with the higher pH nutrient solutions ranged from 5.50-6.00. Sulfur content was lowering in the vegetation period with the nutrient solutions pH 4.50-6.00 and increased with pH 6.50. Dynamics of phosphorus and magnesium contents in the tomato leaves had polydirection trends in different years of study. It was shown high tolerance of tomato on pH nutrient solution ranged from 4.50-6.50. There were no visual symptoms of disorders on the leaves and in growth and development of plants.

The effect of ph nutrient solutions on dynamics
of macroelement contents in the leaves
of greenhouse tomato grown in rockwool

Summary

The effect of nutrient solution pH 4.50-6.50 used for fertigation of greenhouse tomato cv. Cunero F₁ cultivated in rockwool on dynamics of macroelement contents in leaves was examined. The content of nutrients in the index part of tomato (8-9 leaf from the top) was analysed in the middle of June, July and August. It was found, that content of nitrogen increased from June to July and decreased from July to August. The nutrient solution at pH 4.50-5.50 enhanced, but 6.00-6.50 reduced nitrogen content in the leaves. Potassium leaves content increased in the whole vegetation period, and the effect of nutrient solution pH varied in different years of study. In the opposition to potassium, calcium contents decreased during plants growing. Higher levels of calcium in the leaves were related with the higher pH nutrient solutions ranged from 5.50-6.00. Sulfur content was lowering in the vegetation period with the nutrient solutions pH 4.50-6.00 and increased with pH 6.50. Dynamics of phosphorus and magnesium contents in the tomato leaves had polydirection trends in different years of study. It was shown high tolerance of tomato on pH nutrient solution ranged from 4.50-6.50. There were no visual symptoms of disorders on the leaves and in growth and development of plants.