CULTIVO DE TOMATE (LYCOPERSICON ESCULENTUM MILL.) HIDROPÓNICO CON AGUA DESALINIZADA Y DESBORIFICADA EN EL VALLE DE LLUTA 1 HYDROPONIC TOMATO (LYCOPERSICON ESCULENTUM MILL.) CROP WITH DESALTED AND DEBORIFIED WATER IN LLUTA VALLEY

An hydroponic tomato crop (Lycopersicon esculentum Mill.) was grown in a greenhouse at the University of Tarapaca, Agronomy Faculty, in northern Chile (Arica, Tarapaca Region) to study the effect of a controlled environment and the water quality on the crop yield and fruit quality. The study had four treatments: T1 nutrient solution made with Lluta river water (EC 3.96 dS m-1; 7.1 ppm B); T2 nutrient solution made with desalted and deborified (treated) water + boron (EC 3.1 dS m -1 ; 7.1 ppm B); T3 nutrient solution made with treated water + magnesium sulphate (EC 3.96 dS m-1; 0.8 ppm B); and, T4 nutrient solution made with treated water (EC 3.1 dS m -1 ; 0.8 ppm B). The tomato crop harvest was made through the fifth cluster (120 days from transplant) and the yield for every treatment was: T1 = 40 t ha-1, T2 = 39 t ha-1, T3 = 64 t ha-1 and T4 = 61 t ha-1. It was found that excess boron reduced the total tomato yield by 40% and the commercial yield by 55%. All the treatments, however, had higher yield than those reported for tomato grown in the Lluta valley (30 Mg ha-1). It was concluded that growing tomatoes hydroponically in greenhouses is an alternative to the Lluta valley to raise the crop yield, and that the first conditional in this valley is its high water boron content.