Control of Damping off and Increasing Some of the Growth Traits in Greenhouse Cucumber Using Citrus Wood Vinegar

One of the methods of plant disease control especially in organic farming is the use of natural ingredients. In this study, the inhibitory effects of volatile and non-volatile metabolites of wood vinegar (Pyrolignious acid) on the mycelial growth of Phytophthora drechsleri and Pythium aphanidermatum and on the growth traits of the greenhouse cucumber were studied in vitro and in situ conditions. To study the effect of non-volatile metabolites, mycelial disks were placed on PDA culture medium containing 0, 0.025%, 0.05%, 0.125%, 0.25%, 0.37%, 0.5% and 0.75% of wood vinegar. To study the effectual volatile metabolites mycelia disks placed on one side of walled-petridishes, while on the other side, the above-mentioned concentrations were added. Both volatile and non-volatile metabolites inhibited significantly (at 0.05 probability level) the fungal growth P. aphanidermatum and P. drechsleri in vitro conditions. In greenhouse conditions, cucumber seedlings were transplanted into pot soil inoculated with fungus. Three concentrations of wood vinegar showed the maximum inhibitory effect on mycelial growth. Disease severity was significantly reduced in all concentrations used (α= 0.05). All concentrations of wood vinegar significantly increased the weight, length and height of the plants compared to the control (α= 0.05).