اثر ضد قارچی غلظت‌های مختلف عصاره گل محمدی بر رشد پرگنه و تندش اسپور برخی جدایه‌های Botrytis cinerea

Biocontrol by using natural compounds is one of the strategies for control of plant diseases. In recent years, many researchers have studied the antifungal, antibacterial and insecticidal effects of essential oils and plant extracts. The antifungal activity of Rosa damascena extract on spore germination and colony growth of Botrytis cinerea (the causal agent of gray mold in fruits and ornamental plants) was evaluated in this study as completely randomized design for factorial experiments. Four isolates of B. cinerea (isolated from strawberry, tomato, grape and Rose host plants), one plant extract (Rosa damascena), 5 concentrations of the plant extract (0, 10 20, 40 and 80 mg/ml) and 3 replicates for each treatment were used. The plant extract were extracted from Rosa damascene flowers, concentrated, sterilized and prepared as concentrations desired. Sterile PDA plates containing desired concentration of the plant extract were inoculated with a 5 mm diameter mycelial agar discs of each isolate and incubated at 24°C and dark regime and the colony diameter was measured daily. The antifungal effect of Plant extracts on spore germination of B. cinerea were evaluated using micro-dilution technique. The study was conducted as described for colony growth but with 2 isolates of B. cinerea and 3 replicates for each treatment. Wells in micro plates were loaded with 105 conidia of each B. cinerea isolates and 150 µl of each plant extract concentrations. The controls includes one with spores and no extract and the other a blank without spore. Subsequent changes in optical density following spore germination in the wells was measured using an Elisa reader after 24 h incubation at 24°C and dark regime. The data were statistically analyzed with SAS software. The results showed that increasing in concentration of the Rosa damascena extract led to enhance colony growth and also spore germination of all B. cinerea isolates examined in this study. Therefore the results of this study showed that using the Rosa damascena extract is not a suitable option for control of B. cinerea.