Especialización patogénica de Rhynchosporium secalis en los valles altos de México

Abstract

The pathogenic variability of the barley scald fungus [Rhynchosporium secalis (Oud.) Davis] was studied using 26 isolates. The isolates came from various localities of the Central Region of Mexico. Five groups with different pathogenicity were identified according to the reaction of the varieties ´Zoapila´, ´Osiris´, ´Trebi´and ´Wisconsin Winter x Glabron´ under greenhouse conditions. Environmental conditions, particularly temperature, affected the symptoms expression of some of the varieties used as differentials. Therefore the determination of pathogenic vaces should be done under controlled conditions.