Main Article Content
Climatic and technical factors influence tomato (Solanum lycopersicum L.) production in hydroponics and greenhouse, but there is not much research on management of red volcanic rock as substratum, as well as on water and nutrient solution. Therefore, the effect of the concentration of nutrient solution, irrigation frequency and the volume of substratum on growth, dry matter and fruit production was evaluated, and the economical impact was compared according to costs and yield. During 2007 and 2008, in the Experimental Field of the Universidad Autónoma Chapingo, Chapingo Mexico, concentrations of nutrient solution (100, 75, and 50%), irrigation frequency d-1 (1, 4, 7, and 10), and volumes of substratum plant-1 (5, 10, and 15L) were assessed in a completely randomized block design in a factorial treatment arrangement replicated three times. The results showed significant differences (P<0.05) between years, concentrations of nutrient solution, irrigation frequency, and volumes of substratum in growth and yield of dry matter and fruit. In 2008, there was major growth and yield of dry matter and fruit, compared to 2007. Nutrient solution at 75% diminished the fruit yield by 4.8% compared to 100%. With 7 irrigations d-1, stem thickness was reduced by 2.1, 1.8, and 1.7%, and the index of leaf area, and fruit yield, respectively, was compared to ten irrigations d-1. There were no differences between 10 and 15L in fruit yield. It is concluded that it is convenient to utilize the nutrient solution at 75% in seven irrigations d-1 and substratum volume of 10L for tomato production in hydroponics and greenhouse in order to obtain the highest profit (73.9%).