Abstract:Changes in the cell surface glycoproteins in common wheat 3B-2, Agropyron intermedium and octoploid wheat-wheatgrass Zhong 5 after the inoculation with barley yellow dwarf virus (BYDV) were sdudied using electron microscopy and ruthenium red staining. The results indicated that, after the inoculation with BYDV, different changes in cell surface glycoproreins were observed in the plant species with different levels of resistance. In A. intermediurn which is immune to BYDV, inoculation with BYDV did not cause significant change in cell surface glycoprotein layer. In cotoploid wheat-wheatgrass Zhong 5 which is highly resistent to BYDV, BYDV infection caused significant thickening in most cell surface glycoprotein layer. In common wheat 3B-2 which is susceptible to BYDV, BYDV infection did not cause thickening in cell surface glycoprotein layer, but in most cells, glycoproteins on the cell surface were partially peeled off or disappeared completely. Therefore, it is suggested that the glycoproteins on cell surface play certain roles in BYDV resistance. The phenomenon of the thickening of cell surface glycoprotein layer caused by BYDV infection was possibly a resistant reaction to the virus.