Mitigation of cucumber autotoxicity in hydroponic culture using microbial strain

Effects of a microbial suspension (bacterial strain) on the autotoxicity of cucumber plants grown by hydroponic culture with or without addition of 2,4-dichlorobenzoic acid (DCBA) to the nutrient solution were investigated. The growth and fruit yield of cucumber plants significantly decreased on the addition of DCBA (10 μmol/l) to the nutrient solution. The growth, however, recovered upon addition of the microbial strain. The yield reduction of cucumber plants for non-renewal of the nutrient solution was also checked when the strain was added to the nutrient solution at 2 weeks after the initial harvest. This result suggested that microorganisms, if added to the nutrient solution at the reproductive growth stage of cucumber, can catabolize autotoxic substances from root exudates into nontoxic substances and this results in an increase in fruit yield of cucumber plants.