International Symposium on Soiless Cultrue and Hydroponics, Almeria, Spain, 14 - 19 November 2004, pp.399-408
The objective of the present study was to investigate the accumulation of nutrient elements in the root zone, nutrient uptake, changes in substrate's electrical conductivity, plant growth and the fruit yield underopen and closed hydroponics systems. The tomato cultivar Ferrari F-1 was used as plant material and grown in perlite in glasshouse experiment. In the open system nutrient solution drainaged freely, on the other hand in the closed system drainage solution turn back to the nutrient tank. In the closed system nutrient solution renewed when EC value reached to 4.5 dS/m in the nutrient tank. Substrate analyzed for Na, H2PO4, SO4, NO3, Mg, Cl, Ca, K, Mn, Fe, Zn, Cu content and EC value within 15 days intervals. Foliar analyses were done with 30 days intervals for Cu, Mn, Fe, Zn, Mg, N, K, P, Ca and Na. From five clusters 59.9 ton/ha fruit obtained from closed system while 68.7 ton/ha fruit obtained from open system. 252.5 and 90.3 litres/plant, nutrient solutions were used in open and closed systems respectively during 26 weeks of cultivation. EC value of the substrates finally reached 4.80 and 2.97 dS/m in closed and opensystems respectively. The concentrations of the tab water for Na, Cl, Ca and Mg caused moderate to important accumulations of these minerals espeClally in closed system. SO4, NO3-N and K accumulations were not determined in the both systems. Moderate accumulation can be mentioned for H2PO4-P. Micro nutrient's accumulations were not important.