Integrated effects of wood vinegar and tea compost on root rot and vine decline and charcoal root rot diseases of muskmelon

Root rot and vine decline disease caused by Monosporascus cannonballus and charcoal root rot disease caused by Macrophomina phaseolina are important diseases of melon plants in Iran. In this study, the efficacy of wood vinegar on the mycelial growth of these pathogens as well as the integrated effect of wood vinegar and compost tea were examined on the control of root rot and vine decline disease. To test the antifungal activity of wood vinegar, mycelial disks (3 mm in diameter) of M. cannonballus and M. phaseolina were placed on PDA culture media amended with different concentrations of wood vinegar (0.025, 0.05, 0.37, 0.5, 0.75 v/v). Wood vinegar inhibited the mycelial growth of both pathogens at 0.05 probability level. In green house condition, muskmelon seeds were sown into pot-soil containing 15% v/v of compost tea and infested with M. cannonballus. Three concentrations of wood vinegar (0.125%, 0.25%, 0.5%) which had shown the maximum inhibitory effect on mycelial growth in the laboratory were then drenched into the soil. Results showed that disease severity was significantly reduced in all concentrations used (α= 0.05). The integration of compost tea and wood vinegar reduced the pathogenicity of M. cannonballus up to 94% compared with untreated control. Roots and shoots weights increased by 8% and 25% respectively in the presence of wood vinegar and compost tea (α= 0.05).