Prevalence of benzimidazole resistance in Botrytis cinerea isolates from Rose greenhouses in Center of Iran

• Published in: Phytopathology Vol. 100; no. 6; p. S62
• Main Authors: Khazaeli, P, Zamanizadeh, H, Morid, B, Hajmansoor, S
• Format: Journal Article
• Language: English
• Published: 01.06.2010
• Subjects: Botrytis cinerea
• ISSN: 0031-949X

Botrytis cinerea Pers. is a phytopathogenic fungus which causes grey mould on over 230 hosts. Development of fungicide resistance is now one of the major problems in plant disease control. The widespread use of fungicides, such as benzimidazoles, in the prevention or elimination of fungal attack has resulted in the appearance of resistant strains. This study was conducted to evaluate the sensitivity and resistance response to benzimidazole of 51 isolates of B. cinerea were obtained from Roses are cultivated under greenhouses in Tehran and Markazi provinces of Iran. The isolates were identified at the species level by their morphological characteristics and molecular method with used specific primer. Threshold concentrations for evaluating the resistance were 1 ppm for sensitive, 50 ppm for resistance and 500 ppm for high resistance. Results showed that 42% of isolates grew on PDA containing 500 ppm benomyl and showed the high resistance phenotypes, whereas all other isolates were inhibited by this concentration and grew on PDA containing 1 ppm benomyl and showed that sensitive phenotypes. According to the results, the resistance of Botrytis cinerea isolates to benzimidazole is increasing in rose producing greenhouses of Iran and this widespread occurrence of resistance to benzimidazole fungicides suggests that their efficacy against grey mould might be impaired and that more aggressive resistance management is needed.