Hydroponic cultivation of salad rocket using saline nutrient solutions

Abstract

This study aimed to determine the tolerance of the salad rocket to the salinity of nutrient solution. The experiment was carried out in a greenhouse in the experimental area of the Irrigation and Drainage Section of the University of São Paulo (ESALQ/USP), Piracicaba, State of São Paulo, Brazil. The experimental design consisted of randomized blocks.Nine saline nutrient solutions obtained with the addition of NaCl with EC: 1.8, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5, 10.5 dS m^-1 were evaluated. The number of leaves, aerial fresh and dry biomass, root dry biomass, water content in aerial parts and ratio of aerial parts and root dry biomass were analysed. The results obtained show that the increase in levels of salinity of nutrient solution caused a reduction in all parameters except the number of leaves which was not affected significantly and the ratio root/shoot was influenced incrementally. The threshold salinity was found to be 2.57 dS m^-1, with 5.57% of reduction in production for each unit increase in salinity. The salad rocket was classified as moderately sensitive to salinity.