Abstract:Yan-xiao-hei 1-1 and 81-7241 are two wheat lines highly resistant to powdery mil-dew at present in Sechuan Province.Results of studies indicated that the resistance ofYan-Xiao-Hei 1-1 to isolate 411 was conditioned by 2 dominant major genes,whereasthat of 81-7241 by 1;all of them highly effective th