Evaluation of nutrient solution recirculation methods for tomato production in short cycles

Abstract

Tomato (Solanum lycopersicum L.) is the most grown vegetable in greenhouse and hydroponics. For easy handling, open hydroponic systems (without recirculation of the nutrient solution) with substrate are the most commonly used in the world. Closed systems (with recirculation) save water and fertilizers, but their technical management is difficult, because over time, the ions less consumed by the plant accumulate, which, when recirculated, cause nutritional imbalances and increases in the EC to levels that affect growth and yield, in addition to the high risk of spreading diseases, especially with cultivation cycles as long as conventionally the tomato is managed. The objective was to compare three methods of recirculation of nutrient solution against an open system, in the agronomic behavior of tomato managed in high population density with cuts to harvest only three clusters per plant. The design was randomly complete blocks with four treatments and seven repetitions, with experimental unit of 20 m2. Morphological variables, dry weight and yield were evaluated. Except for height and diameter of stem, no variable showed statistical difference between treatments. It is concluded that, with the management of the tomatoes plants to harvest three clusters, in a cycle as short as 110 days of transplantation at the end of harvest, it is feasible to use any nutrient solution recirculation system without nutritional imbalances, so that comparing these methods with an open system does not affect the growth or yield of the plants, saving water and fertilizers.