EFFECT OF NUTRIENT SOLUTION CONCENTRATION ON GROWTH, YIELD AND QUALITY OF OFF-SEASON CELERY IN CIRCULATING HYDROPONICS

Abstract

The research was conducted to determine the effects of 4 concentrations (800 ppm, 1,000 ppm, 1,200 ppm and 1,400 ppm) of inorganic nutrient solution on growth, yield and quality of celery in circulating hydroponics. The experiment was carried out in the plastic house and laid out in randomized complete block design with 4 replications. The results indicated that plants grow best with highest yield (439.29 kg/100 m²) at concentration of 1200 ppm compared to other treatments at 95% of confidence. Even though treatment 4 (1,400 ppm) contained high concentration, obtained yield was lowest due to that plants intend to absorb more water than minerals from nutrient solution. NO₃^- content in all treatments was reduced 1.9 - 2.3 times after 10 days of quarantine before harvesting and under allowed limitation of nitrate content for safe products. It can be concluded that the suitable nutrient solution concentration for growing celery in circulating hydroponics is 1200 ppm.