Pectic substances extracted from cabbage cell walls with water, at 80°, and (NH4)2C2O4, at 80°, accounted for 45%(w/w) of the purified cell wall material. Only a small amount of neutral arabinan was isolated. Partial acid hydrolysis and methylation analysis revealed that the major pectic polysaccharide had a rhamnogalacturonan backbone to which The roles of aspartic proteinase and endo-pectin lyase enzymes in the primary stages of infection and pathogenesis of various host tissues by different isolates of Botrytis cinerea Pers ex. Pers