ELECTRICAL CONDUCTIVITY OF NUTRIENT SOLUTION AND THEIR EFFECT ON BIOACTIVE COMPOUNDS AND YIELD OF BELL PEPPER (Capsicum annuum L.)

Background . The electrical conductivity (EC) of a nutrient solution (NS) in hydroponic or soilless systems influences the yield and quality of the fruits. Objective . The aim of this research was to determine the quality and fruit yield of bell pepper in response to the electrical conductivity of the nutrient solution. Methodology . A completely randomized experimental design with 15 replications was used. The treatments consisted of four nutrient solutions with different electrical conductivity (1.5, 2.0, 2.5 and 3.0 dS m -1 ) based on the Steiner nutrient solution. Yield, firmness, and bioactive compounds (phenolic compounds, vitamin C, lycopene, β-carotene, and the antioxidant activity) were quantified in fruits. Results . The results showed that an electrical conductivity of 2.0 dS m -1 or higher increased the bioactive compounds but decreased the yield and firmness of the fruits. Implications . The correct selection of the EC in the NS is a preponderant factor to get functional foods, with high yields and to avoid unnecessary costs in fertilization Conclusion . The high EC in the NS reduced the yield and the firmness of the fruits. From an EC of 2.0 dS m -1 in the NS, the content of vitamin C, total phenols, lycopene, total capsaicinoids, β-carotene and the antioxidant activity of pepper fruits increased.