Influences of Metabolic Inhibitors and Hydrolytic Enzymes on the Adhesion of Appressoria of Pyricularia oryzae to Wax-coated Cover-glasses.

For discovering the components that contributed to the bonding strength of the glue substances produced by appressoria of Pyricularia oryzae on wax-coated cover-glasses, the influences of metabolic inhibitors and hydrolytic enzymes were investigated. The bonding strength of appressoria was assessed by the ratio of the remaining appressoria after sonication to the appressoria formed before sonication. Remaining appressoria decreased with increasing concentrations of cerulenin, an inhibitor of lipid synthesis, but isoprothiolane and compactin showed no influence on bonding strength. Tunicamycin, an inhibitor of glycoprotein synthesis, weakened the bonding strength of appressoria, but castanospermin had no effect. Of the hydrolytic enzymes tested, protease particularly weakened the bonding strength of appressoria. On the surfaces of substrata, the appressoria's bonding strength was higher on the hydrophobic surfaces than on the hydrophilic. These results suggest that lipid components and glycoprotein were closely associated with appressoria bonding strength to the surface of wax-coated cover-glass.