Response of the mushroom pathogen to prochloraz and metrafenone fungicides and actinobacteria.

After an outbreak of cobweb disease of cultivated button mushroom in Serbia in 2003, the isolated fungal pathogen was initially identified as (teleomorph ) based on morpho-physiological traits. Molecular analysis indicated re-classification of two strains (isolated in 2004 and 2007) as (teleomorph ). However, subsequent analysis of further five strains (isolated over the period 2003-2010) within the frames of the present study, also confirmed their identification as the exclusive cobweb causal agent After artificial inoculation, the symptoms observed on harvested and growing mushrooms were consistent with the appearance of cobweb disease. Pathogen sensitivity to fungicides was estimated by probit analyses. Fungicide susceptibility tests showed that strains were highly sensitive both to prochloraz (ED<0.087 µg mL) and the newly introduced metrafenone (ED<0.15 µg mL). Furthermore, the growth of all examined strains of was significantly inhibited by the indigenous actinobacterial strain A06. A dual culture assay showed after 72 h that the percentage of radial growth inhibition of the pathogen ranged from 22.38 to 55.73%. Our findings suggest that the antagonistic A06 might be a potential candidate for controlling the cobweb disease of cultivated button mushroom.