Toward a coherent model of host-pathogen interactions in tan spot of wheat: An epilogue to the Third International Workshop on Tan Spot of Wheat

Tan spot, caused by the ascomycete Pyrenophora tritici-repentis (Ptr), is a n economically important disease of wheat worldwide. In the past decade, ph ysiologic variation in the pathogen and host-pathogen interactions in the w heat-Ptr system wheat were extensively investigated by several independent research groups. This paper provides a synthesis of this research activity and proposes a working model of host-pathogen relations in the wheat-Ptr sy stem, integrating our current knowledge of physiologic variation in the pat hogen, inheritance of host reaction and involvement of host specific-toxins in the disease.