بررسی اثرضد قارچی باکتری Bacillus velenzensis UTB96 و آنتی‌ بیوتیک ناتامایسین در کنترل بیماری پوسیدگی خاکستری ناشی از قارچ Botrytis cinerea

Strawberry with the scientific name (Fragaria x ananassa) belongs to the family Rosaceae is a small fruit that is of great economic importance all over the world. This disease is known as the second fungal pathogen in the world, which causes heavy and huge damage to fruits before and after harvest. Botrytis cinerea, the causative agent of gray mold, is one of the most important pathogens of strawberry plants. This pathogen was isolated from the strawberry plant in the greenhouse of Karaj city and identified by morphological and molecular methods. According to the results of morphological identification and sequencing of ITS1-4 region, the desired isolate belonged to B. cinerea species. In order to investigate the effect of natamycin as well as the antagonistic properties of Bacillus bacteria. B. velezensis UTB96 in the control of this disease, different concentrations of natamycin were tested in laboratory and cold storage conditions, both on culture medium and fruit. The results of additional studies showed that a concentration of 20 mg/liter (ppm) of natamycin on the culture medium completely inhibited mycelium growth and conidial germination in laboratory conditions. Contamination of fruit in laboratory conditions with pathogenic spores of B. cinerea showed that natamycin treatments with a concentration of 400 mg/liter at a temperature of 22 degrees Celsius have 97.5% inhibition. Also, contamination of fruit in storage conditions with pathogenic spores of B. cinerea showed that natamycin treatments with a concentration of 300 mg/liter at a temperature of 8 degrees Celsius have 89.47% inhibition. The bacterium B. velezensis UTB96, which is one of the most important and useful strains, showed an inhibition of 60% on mycelium in laboratory conditions. In the control test of gray mold disease on fruit by bacteria in storage conditions, it has shown a significant effect on the inactivity of gray mold fungus. In such a way that it showed 89.47% inhibition of the disease.