Induction and Impact of Cell Wall Degrading Enzymes in Nutrient Solution of Closed Hydroponic Systems

The potential of the microflora in nutrient solutions to produce cell wall degrading enzymes (CWDE) was investigated by adding glucose or substrates of CWDE, such as chitin, cellulose, curdlan and preparations of fungal mycelia (0, 0.01 and 0.1%, w/v). The results indicate the potential of the microflora in nutrient solutions to produce proteolytic, chitinolytic, cellulolytic as well as β‐1,3‐glucanolytic enzymes. All enzyme complexes were induced by addition of preparations of Fusarium oxysporum f. sp. cyclaminis (Focy) and Pythium ultimum, respectively. In contrast, addition of glucose to nutrient solution resulted in only slight increase of protease and chitinase. No correlation between increased activity of CWDE and survival of Focy was found.