THE EFFECT OF NUTRIENT SOLUTIONS ON YIELD AND MACRONUTRIENT STATUS OF GREENHOUSE TOMATO (Lycopersicon esculentum Mill.) GROWN IN AEROPONIC AND ROCKWOOL CULTURE WITH OR WITHOUT RECIRCULATION OF NUTRIENT SOLUTION

Aeroponics creates possibilities to cultivate plants without soil or substrate, ob- taining the optimal yield, saving water and nutrient solutions and do not contaminate the environment. In a three year experiment was shown that the higher total and marketable yields of tomato cv. 'Alboney F1' were in cultivation in rockwool with recirculating nutri- ent solution. Lower yields, however being in the same significance range, were in rock- wool without recirculation of nutrient solution and aeroponic culture with A-1 and A-2 nutrient solutions, but the lowest in aeroponics with A-3 nutrient solution. The saving of nutrient solution in aeroponic culture, in relation to the cultivation in rockwool with non- recirculating system, was 58.1%, but comparing with recirculating system 18.8%. Plants grown in aeroponic culture with application of A-2 and A-3 nutrient solutions had higher contents of N, P and K in leaves than cultivated in rockwool with or no recirculation and in aeroponic with A-1 nutrient solution. All tested nutrient solutions (A-1, A-2 and A-3) in aeroponic culture caused the higher contents of Mg in leaves than in rockwool cultiva- tion. The highest Ca leaves contents were in plants grown in rockwool with recirculationg nutrient solution and aeroponic culture with A-2 and A-3 nutrient solutions. Plants grown in rockwool without recirculation of nutrient solution shown the lowest Ca contents, how- ever there was no symptoms of blossom end rot (BER) on fruits. The yield and macronu- trient status of tomato in aeroponic culture with application of A-1 nutrient solution were similar to the plants grown in rockwool with non-recirculating standard nutrient solution A-2.