INFLUENCE OF GROWTH CONDITIONS AND GRAFTING ON THE YIELD, CHEMICAL COMPOSITION AND SENSORY QUALITY OF TOMATO FRUIT IN GREENHOUSE CULTIVATION

The most popular and efficient growing medium in the soilless crop cultivation consists of rockwool slabs. Nowadays, researchers strive to develop other, more environmentally friendly growing media in horticultural practice. The aim of this work was to assess the effect of growth media and grafting on the yield and fruit quality of tomato in greenhouse cultivation. The tomato cultivar Admiro F, was used in the study. Half of the plants were grafted on the rootstock Maxifort. Tomatoes were cultivated on organic medium coconut fiber slabs and on rockwool slabs, the latter commonly used as the standard growing medium for tomato. Total yield and distribution of fruit weight classes in the total yield were investigated. The chemical quality attributes of tomato fruit, vitamin C, total soluble solids, titratable acidity, total sugars, dry matter, nitrates, phosphorus, potassium and calcium were determined. The total yield of tomato fruits was higher from plants cultivated on rockwool slabs than on coconut fiber slabs, which showed that at present rockwool is a better substrate for tomato cultivated all year round. The fruit weight distribution depended on the substrate used. Plants cultivated on rockwool slabs were characterized by higher fruit weight while those cultivated on coconut fiber slabs showed a tendency to grow smaller. There were no significant differences in the distribution of weights between fruits obtained from grafted and non-grafted plants. The chemical composition and sensory quality were mainly affected by the fruit harvest date and, to a lesser degree, by the substratum used and grafting.