Deviation from the Regression of Infection on Heading and Height as a Measure of Resistance to Septoria tritici Blotch in Wheat

Abstract

(...) A resistance parameter, deviation from the regression of the infection on heading and height, was defined by eliminating the linear effect of escape mechanisms through late heading or tall stature. (...) Germ plasm that originated in areas prone to epidemics by S.t., all of which are under strong maritium influence or are in the Parana River Basin, generally had higher levels of true resistance as well as excape mechanisms, resulting in reduced field infection. For breeding value, however, some earlier, shorter lines showing intermediate infection levels are thought to be superior