RESEARCH ARTICLE

Abstract The chemical structure of the cell wall of two isolates of Verticillium fungicola collected from diseased fruit bodies of the commercial mushroom Agaricus bisp-orus treated with the fungicide Prochloraz-Mn was ana-lyzed. The isolates were obtained during different periods of time and grown in the absence and presence of the LD50 values of the fungicide forV. fungicola. In addition, another V. fungicola isolate collected previous to the routine utilization of Prochloraz-Mnbut grown under the same conditions was also analyzed. The overall chemical composition of the cell wall from the three isolates showed detectable differences in their basic components, with a significant decrease in the protein content in fun-gicide-treated cells. This inhibitory effect was partially compensated by an increase in neutral and/or aminated carbohydrates and was accompanied by appreciable modifications of polysaccharide structure, as deduced after methylation analysis and gas-liquid chromatogra-phy-mass spectrometry (GLC-MS). Moreover, differ-ences in hyphal morphology caused by the fungicide were observed by transmission electron microscopy (TEM)