The tomato hydroponics cultivation is a technique that provides high productivity and a better control of several factors during the production cycle. However, this technique needs improvements such as adequate dosage of nutrients in the nutritive solution. An experiment was carried out in a greenhouse equipped with a nutrient film technique system (NFT). Three commercial cvs. of tomato, UC-82, Saladinha, and T-93, were grown with three Hoagland's solution concentrations, 50%; 75%; and 100%. In the last fruit harvest, 138 days after transference to the NFT system, the accumulation of shoot dry mass, the fruit fresh mass, the number of fruits per plant, the total fresh biomass per plant, the total content of soluble solids (ºBrix) and the productivity, were evaluated. The genotypic characteristics of the cvs. affected strongly the productivity. Generally the ionic concentrations of the nutrition solution did not influence the productivity and the tomato plants mass accumulation. Thus, the usage of solutions with lowest ionic concentration is recommended for the cultivation of the UC-82, Saladinha and T-93 tomatoes, in NFT hydroponics system, in the climatic conditions of Seropédica, Rio de Janeiro State.
Lycopersicon esculentum Mill.; electrical conductivity; tomato cultivars; hydroponics
