8Ayoub M,Guertin S, Fregeau R J,et al. Nitrogen fertilizer effect on breading quality of hard red spring wheat in eastern Canada [J]. Crop Science Society of America, 1994,34(5):1346-1352.
9Pltd J R. Effects of levels and methods of nitrogen application on wheat yield[J]. Journal of Maharashtra Agricultural Universitiea,1999,24:7-9.