Tan Spot Disease of Wheat : race characterization

Tan spot, one of the most important diseases of wheat, is caused by Pyrenophora tritici-repentis, a necrotrophic fungus which survives in wheat straw. Methods of disease control include fungicide application, crop rotation, and the use of resistant cultivars; however, in Brazil there are no cultivars in the market with a good level of resistance. In North America, a system of race identification is used based on symptom development on a differential set of wheat lines. Symptom development on the differential wheat lines is known to be at least partly due to the production of toxins by the pathogen. The Embrapa Trigo, with the collaboration of the USDA-ARS in the USA, has introduced this set of differential wheat lines into the Active Germplasm Bank. Besides the race indentification, a set of microsatellite markers will be used to characterize the P. triticirepentis population from Brazil. The data obtained will be beneficial to the breeding program for the introgression of genes into the Embrapa wheat cultivars. 1 Plant Pathologist Researcher. Embrapa Trigo, Caixa Postal 451, 99001-970 Passo Fundo, RS, Brazil. Email: [email protected]. 2 Plant Pathologist Researcher. USDA, Fargo, North Dakota, USA. E-mail: [email protected].