ارزیابی ژنوتیپ های گندم مربوط به آزمایشات مقایسه عملکرد مقدماتی، پیشرفته و امید بخش ‭(PRWYT, ARWYT ERWYT-N) ‬یکنواخت اقلیم گرم و مرطوب شمال نسبت به بیماری سفیدک پودری ‭(94-1393)‬

Powdery mildew caused by Blumeria graminis f.sp. tritici is one of the most important diseases of wheat in high rainfall and humidity condition. In this project resistance of 354 wheat genotypes includes 264 wheat preliminary genotypes yield trials, 50 advanced wheat genotypes, 20 promising genotypes of 1392 and 20 promising wheat genotypes of uniformly hot and humid zone of north country of 1393 were studied to powdery mildew disease in field conditions in Gorgan and Gharakhyle. After preparing the ground, each genotype were planted in two meters below irrigation system Mist irrigation. Genotypes at seedling stage were inoculated using spore suspensions with distilled water. The notes of reaction genotypes was performed in milky grain with altered states and associates (Eyal et al., 1987) in two numbers (00-99). Cluster according to the severity of infection on susceptible cultivars with some changes are meant to protect: 00-15 resisting means, 16-35means moderately resistant, 36- 55 means half sensitive, 56-75 sensitive means and 76-99 were very sensitive means (Wang et al., 1993). The results of performance tests in two locations (Gorgan and Gharakhyle) is shown in the attached tables (Tables 4-1). Preliminary data tables genotypes notes, advanced and promising show, severity infection was lower in Mazandaran, but in both regions disease appeared at seedling stage, but disease severity in genotypes depending on the environmental conditions of the area. In Gharakhyle experiment despite the incidence of disease in the seedling stage, there was little progress on the upper part of the plant and disease severity was down in the flag leaf and leaf before that, but the incidence and spread of diseases in Gorgan steadily progressed in the upper leaves of the plant. Grouping data on the response of different genotypes of the disease were showed 7.6% hot and humid zone lines were resistant, 26.5% Moderately resistant, 15% semi-sensitive, 15.5% sensitive and 35.2% were very sensitive reaction. None advanced wheat lines of northern region were resistant to disease so that 6% moderately resistant reaction, 36% semi-sensitive and 59% lines showed very sensitive. 15% promising lines of 2014-15 response resistant, 15% moderately resistant, 10% sensitive and 30% were quite sensitive. Also the reaction promising lines of 2013-14 , 15% resistance, 20% moderately resistant, 30% semi-sensitive, 25% were showed sensitive reaction and 10% were very sensitive reaction. Keywords: wheat disease, powdery mildew, resistance