The Ionic Concentration Influences of Nutrient Solutions on the Physico-Chemical Characteristics and Productivity of Two Cherry Tomato Cultivars Cultivated in NFT Hydroponic System

摘要

Fruit growths in hydroponic systems represent a new evolution stage in the hydroponic cultivation systems in Brazil. The tomato production is of great importance for the Brazilian population due to economical, social and food aspects. The experiment was held using the nutrient film technique, aiming to evaluate the physico-chemical characteristics and the productivity of 'Cascade' and 'Sweet Million' cherry tomato cultivar grown in five ionic concentration of nutrient solutions with different electric conductivities (1.5, 2.0, 2.5, 3.0 and 3.5 dS/m). The tomato growth was held in winter/spring seasons and lasted 140 days. The fruits were harvested weekly, evaluating the number, size, yield and physico-chemical characteristics of fruits. The cherry tomato productivity cultivated in nutrient solutions with EC 1.5, 3.0 and 3.5 dS/m were reduced around 10, 14 and 31%, respectively. The productivity of two hybrids tested did not present significant differences. The results of physico-chemical analyses were around 50% increased for total soluble solid (5.6 until 8.3°Brix), lycopene results were up to 70% increased (8.2 until 14.35 mg/100 g). The best results were gotten with nutrient solutions with 2.5 and 3.0 dS m~(-1). Plants cultivated in NFT hydroponic system with the highest ionic concentrations of nutrient solutions presented the highest values for TSS and lycopene.