Secado parcial de la raíz de jitomate: efectos en la fisiología de la planta y calidad de fruto

the aim of this research was to study under greenhouse and hydroponic conditions the effects of two levels of water availability in the substrate of tomato plants (lycopersicon esculentum mill.), upon physiological and quality related characteristics. the trial was conducted in 2003 as follows: may 21th, sowing; july 1st, transplanting; and november 24th, whole plant harvest, respectively. the technique of irrigation followed by partial root zone drying (prd) was used to establish two moisture treatments in the substrate, control (80-80%) and prd (80-30%). the physiological parameters recorded were: leaf area, dry matter weight, plant water relations, and gas exchange, as well as fruit yield and quality (diameter, firmness, total soluble solids, ph and electric conductivity). plants were grown in two plastic bags filled with "tezontle" (volcanic rock) and their root split in two halves and two moisture treatments applied to the substrate, 80-30% (prd) and 80-80% (control)). these treatments were applied at 28 days after transplanting and were maintained throughout the experiment. results indicate that prd and control treatment did not show any significant difference in relation to the physiological parameters recorded; however, the fruit quality traits such as °brix, firmness and electric conductivity increased without affecting fruit yield under prd treatment.