Isolation and Diagnosis of Sclerotinia Sclerotiorum (Lib) Debary Fungus that Causes White Mold Disease on Eggplant Plants in Iraq and the Effectiveness of Some Elements of Biological Control in Inhibiting It in Vitro
The isolation and diagnosis of the fungal growth growing from the Sclerotia on the PDA culture media showed that several different isolates and different regions of the pathogenic fungus Sclerotinia sclerotiorum. The results of migrating the PCR products on agarose gel were shown by giving a band of 500-580bp for S. sclerotiorum fungus, 550bp for Penicillium commune fungus, and 590 for Trichoderma. asperellum fungus, where these two fungi are used in the biological control for the pathogenic fungus S. sclerotiorum . The isolates of this pathogen a significant reduction in the percentage of germination of radish seeds grown on the water agar media compared to the control treatment that amounted to 100%, where the percentage of germination ranged between 0.00-53.0%.It was also found that all the tested isolates of the S.sclerotiorum were pathogenic to eggplant seedlings, and the severity of infection ranged from 86.1 to 50.0%, compared to the control treatment which its infection severity amounted to 0.0%. The results showed that there was a high Antagonistic Potential between the elements of biological control and the S. sclrerotiorum in vitro compared to the control treatment which amounted to 0.0% , where the bacteria treatment of Pseudomonas fluorescens gave the highest percentage of inhibition amounted to 100%, followed by the treatment of the P. commune fungus which amounted to 86.1% .The treatment of Trichoderma viride and T. asperellum fungi gave a percentage of inhibition amounted to 72.8% and 70.0%, respectively, where no significant differences were observed between them in the percentage of inhibition compared to the control treatment, which amounted to 0.0%.The percentage of inhibition amounted to 100% using the topsin fungicide, while the treatment of humic acid and folic acid did not give any percentage of inhibition which amounted to 0.0%.