Characterization of Pyrenophora tritici-repentis (Tan Spot of Wheat) Races in Baltic States and Romania

  • Abdullah, Sidrat (Department of Agronomy, Horticulture and Plant Science, South Dakota State University) ;
  • Sehgal, Sunish Kumar (Department of Agronomy, Horticulture and Plant Science, South Dakota State University) ;
  • Ali, Shaukat (Department of Agronomy, Horticulture and Plant Science, South Dakota State University) ;
  • Liatukas, Zilvinas (Institute of Agriculture, Lithuanian Research Center for Agriculture and Forestry) ;
  • Ittu, Mariana (National Agricultural Research and Development Institute Fundulea) ;
  • Kaur, Navjot (Department of Agronomy, Horticulture and Plant Science, South Dakota State University)
  • Received : 2016.10.10
  • Accepted : 2016.12.11
  • Published : 2017.04.01


Tan spot, caused by the fungus Pyrenophora tritici-repentis, is economically important foliar disease in Latvia, Lithuania, and Romania; however, race structure from Baltic States and Romania is not known. In this study, we performed genotypic and phenotypic race characterization of a large collection of P. tritici-repentis isolates from these countries to determine race structure and utilize this information for better disease management and breeding wheat for tan spot resistance. We characterized 231 single spore isolates from Latvia (n = 15), Lithuania (n = 107), and Romania (n = 109) for Ptr ToxA and Ptr ToxB genes using two genes specific primers. A subset (139) of 231 isolates were further characterized for their race structure by inoculating them individually on tan spot wheat differentials set. Majority (83%) of the 231 isolates amplified Ptr ToxA gene suggesting prevalence of race 1 and 2. Further, phenotypic characterization of 139 isolates also showed wide prevalence of races 1 (68%), 2 (8%), 3 (11%), and 4 (5%) were also identified from Baltic States as well as Romania. Eighteen of the isolates (13%) did not seem to be of any of the eight known races as they lacked Ptr ToxA gene but they behaved like either race 1 or race 2, suggesting possibility of novel toxins in these isolates as their virulence tools.


Supported by : South Dakota Wheat Commission, SDSU Agricultural Experiment Station (AES)


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