Response of wheat cultivars to infection by Stagonospora nodorum isolates/mixture on detached and intact seedling leaves

Stagonospora nodorum blotch (SNB) of wheat caused by Stagonospora nodorum (Berk.) Castellani & E.G. Germano is among the major foliar diseases of wheat worldwide. The response of four wheat cultivars for reaction to infection by isolates/mixture of S. nodorum was tested on detached and intact seedling leaves in the laboratory and glasshouse experiments, respectively. The four wheat cultivars tested significantly differed from each other in response to infection by the isolates/mixture of S. nodorum. Similarly, the aggressiveness of the four isolates/mixture of the pathogen on the four wheat cultivars was significantly different as demonstrated by the parameters tested in the two experiments. However, no significant (p ≤ 0.05) isolate x cultivar interaction was observed for all the parameters tested in the two experiments. Highly significant positive or negative correlations were observed between parameters, i.e., disease severity (DS), incubation period(IP), and size of necrotic lesions (SNL), tested on detached and intact seedling leaves, respectively. This suggests that use of the detached leaf technique has considerable promise for quick screening of wheat cultivars against SNB. This revised version was published online in August 2006 with corrections to the Cover Date.