Evaluation of Resistance of some Wheat Commercial Cultivars and Elite Lines to Four Pathotypes of Puccinia striformiss f. sp. Tritici

In this research, resistance of the 45 elite wheat lines and 21 wheat commercial cultivars were studied relative to the 4 wheat yellow rust pathotypes in completely random blocks design in three replications. This study was conducted in seedling stage in 2010-2011. Isolates were collected from Mazandaran, Moghan and Mashhad provinces. In order to determine pathotypes and virulence factors, the isolates of 44 isogenic lines or international lines were used. The result of the study of 4 pathotypes showed that race 166E150A+ (Moghan) has the most pathogenicity and race 134E146A+ (Sari) has the less pathogenicity. In order to determine of resistance, the commercial wheat cultivars and lines were planted in pots in thickness of 12 cm and the seedlings were inoculated with fungi of pathogen in one- two leaves stages. The pots were transferred into greenhouse in temperature of 17- 19°C, humidity of 55-65% and 12 h light. The bushes were investigated separately ten days after inoculation. This trend continued 5 days for measuring latent period and finally the infection type was noted based on scale (0-9) in day of 14th after inoculation. After data analysis, the lines and cultivars of C-85D-9, C-85D-13, MV17, C-86-6, M- 85-7, C-85-6, C-86-3, C-83-7, C-84-8, S-80-18, C-84D-55, C-85D-8, M-86-9, C-86-5, Dena, Sivand, Pishgam, Parsi, Gaspard, Niknejad and Karkheh were reported resistant against infection type and latent period and lines and cultivars of WS-86-14, S-83-4, WS-85-10, S-85-19, MS-84-16, S-83-3, WS-86-11, MS-85-15, WS-86-13, Alvand, Arg, Bolani and Shahriyar were reported sensitive from infection type and latent period view point.