AUTONOMOUS MANAGEMENT OF FERTIRRIGATION OF GRAPE TOMATO CULTIVATED ON A SUBSTRATE USING IRRIGÁS® SENSORS

Abstract

The association of Irrigás^® sensors with autonomous irrigation controllers enables the development of new researches to correlate with greater precision the level of substrate moisture and the productivity and quality of tomatoes gourmet. The aim of this study was to analyze the production and quality of grape tomatoes as a function of autonomous fertigation management based on Irrigás^® sensors at different water tensions of the cultivation substrate. A randomized complete block experiment was conducted, with six replications, and five minimum levels of substrate moisture for the beginning of fertigation: 3.0; 4.3; 5.6; 6.9; and 8.2 kPa. Fruit yield and fruit mass, soluble solids content, titratable acidity and firmness of the fruit pulp were evaluated. The highest commercial fruit production (3.4 kg/plant) was obtained with the estimated limit tension of 6.0 kPa. The increase in the limit tension for the beginning of irrigation promoted a decrease in the firmness of commercial fruits (4.0 to 3.4 lb) and in the weight of medium-small class fruits (6.7 to 5.8 g/fruit) and increase in the soluble solids content (8.9 to 9.8^oBrix) and titratable acidity (1.0 to 1.2%) of the tomato.