Soluble proteins and multiple forms of esterases in leaf tissue at first and flag leaf stages of spring barley plants in relation to their resistance to powdery mildew (Erysiphe graminis f.sp. hordei)

Abstract

Electrophoretic patterns of soluble proteins and multiple forms of esterases were studied in non-infected first and flag leaves of six barley cultivars showing various levels of resistance to powdery mildew. Although the pattern of soluble acidic proteins was similar for all the cultivars tested, some low molecular weight proteins observed in the first leaves were absent in the flag leaves. The appearance of some multiple forms of esterases was genotype-dependent, irrespective of the stage of plant development, whereas the esterase pattern of the first and flag leaves showed characteristic differences, irrespective of the barley genotype. With regard to the different multiple forms of esterases, the barley cultivars tested were classified into three groups which also differed with regard to mildew resistance: (i) Mari S and Peruvian (highly susceptible to powdery mildew), (ii) Villa, Asse (adult plant resistant) and Stamm 4171 (moderately resistant) and (iii) Rupee (highly resistant). The possible significance of this correlation was discussed.