Assessment of partial resistance of wheat cultivars to Phaeosphaeria nodorum in Iran

Stagonospora nodorum bloch (SNB) is an important fungal disease of durum and common in many parts of the world. The objective of this research was to evaluate 26 wheat cultivars for seedling resistance to SNB. Utilization of host resistance is considered to be the most important and preferred method to control disease. S. nodorum was isolated from naturally infected wheat ears cultivated in different fields of Iran. Infected segmented with pycnidia were placed on Petri dishes containing Yeast Sucrose Agar. Out of 200 isolates of the pathogen that were collected from different parts of Iran, 15 isolates were selected for pathogenicity test. Experiments were carried out in complete randomized block design with three replicate. Comparison of the mean of disease severity. Using Duncan’s multiple range test, divided the isolates into & four groups. The most of disease severity was related to 3 isolates of Fars Province. Based on cultivar- isolates interaction results. Chamran and Back Cross Roshan were resistant and susceptible to SNB respectively.