دراسة مرض ذبول البطيخ المتسبب عن الفطرين Fusarium oxysporum f. sp. melonis و Macrophomina phaseolina و طرائق مكافحته

Results obtained from this study showed the compatibility between the pathogens fusarium oxysporum f. sp. melonis and macrophomina phaseolina and melon plants cv. galia f1 causing a severe disease. both fungi were isolated from infected plants collected from the fields located in the dujail and ishaqi areas of salah al-din governorate. disease incidence and severity of infection with both pathogens when inoculation was done through seed and seedling treatments were 100.00%, 0.66 and 86.66%, 0.54, respectively. when different control treatments such as the biological product trichosone (t. harzianum), salicylic acid (sa), humic acid (h) and agricultural sulfur (s) were applied, by using seed treatment or watering the seedlings, an increase in the concentration of peroxidase, chitinase and polyphenol oxidase enzymes was obtained. results obtained also showed a significant superiority for the triple interference treatment, the biological preparation trichosone for the fungus t. harzianum, salicylic acid, and humic, and by the method of the seedling treatment, and it achieved the highest enzyme activity of 68.50, 79.22, and 3.84 units/ml, respectively, which reflected positively in reducing the incidence and severity of infection as they reached 23.33% and 0.08%, respectively, compared to the control contaminated with the pathogen, which reached 100.00% and 0.66, respectively.