Location: Cereal Disease LabTitle: Virulence of Puccinia triticina in Turkey and leaf rust resistance in Turkish wheat cultivars Author
|Kolmer, James - Jim|
Submitted to: European Journal of Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/3/2012
Publication Date: 10/14/2012
Citation: Kolmer, J.A., Mertz, Z., Akan, K., Demir, L., Unsal, R., Sermet, C., Keser, M., Akin, B., Morgounov, A. 2012. Virulence of Puccinia triticina in Turkey and leaf rust resistance in Turkish wheat cultivars. European Journal of Plant Pathology. 135:703-716. Interpretive Summary: Wheat is attacked by the rust fungus called Puccinia triticina, which causes the disease wheat leaf rust. Wheat leaf rust is an important disease in the humid coastal regions of Turkey. There are many different forms or races of the wheat leaf rust fungus that vary in their ability to attack different resistance genes in wheat. The objective of this study was to characterize the population of Puccinia triticina in Turkey and to determine which genes for leaf rust resistance are present in wheat cultivars that are grown in Turkey. In 2009 and 2010, 44 different races of leaf rust were found in Turkey. Four races were found in both years. The races found in Turkey were very different compared to the races found in the United States. Forty three different Turkish wheat cultivars were tested with 13 races of P. triticina from Canada, the United States, and Turkey. Based on infection with the different races, eight different leaf rust resistance genes were detected in the Turkish wheat cultiavrs. Two other leaf rust resistance genes that optimally give resistance as mature plants were found in the wheat cultivars by using DNA based markers. In field plots wheat cultivars with different combinations of leaf rust resistance genes had the best overall resistance. No single leaf rust resistance gene gave good resistance in the field plots. The results of this study can be used by wheat breeders and plant pathologists to add new genes for leaf rust resistance in Turkish wheat cultivars to improve their leaf rust resistance.
Technical Abstract: Leaf rust caused by Puccinia triticina is a common disease on wheat in the coastal regions of Turkey. Collections of P. triticina from infected wheat leaves were obtained from the main wheat production zones of Turkey in 2009 and 2010. A total of 104 single uredinial isolates were tested for virulence on 20 lines of Thatcher wheat that differ for single leaf rust resistance genes. Forty-four different virulence phenotypes were identified over both years. Four phenotypes were found in both years. Phenotype FHPTQ found in 2009, with virulence to genes Lr16, Lr26, Lr3ka, Lr17, Lr30, LrB, Lr10, Lr14a, Lr18, Lr3bg, and Lr14b, was the most common phenotype at 15.4% of the total isolates. Forty-three winter and spring wheat cultivars from Turkey were tested as seedlings with 13 different P. triticina virulence phenotypes from Canada, the US and Turkey. The infection types on the cultivars were compared with infection types on the Thatcher near isogenic lines to postulate the presence of seedling leaf rust resistance genes in the cultivars. Resistance genes Lr1, Lr3, Lr10, Lr14a, Lr17, Lr20, Lr23, and Lr26 were postulated to be present in the Turkish wheat cultivars. DNA of the wheat cultivars was tested with PCR markers to determine the presence of the adult plant resistance genes Lr34 and Lr37. Marker data indicated the presence of Lr34 in 19 cultivars and Lr37 in four cultivars. Field plot evaluations of the wheat cultivars indicated that no single Lr gene conditioned highly effective leaf rust resistance. Resistant cultivars varied for combinations of seedling and adult plant resistance genes.