The identification and characterization of pathogenicity factors are essential to an understanding of the molecular events that regulate the interaction of plant-pathogenic microbes with their hosts. We have isolated the gene that encodes a host-selective toxic protein produced by the fungus Pyrenophora tritici-repentis and confirmed that this gene functions in the plant as the primary determin...

The necrotrophic fungal pathogen Pyrenophora tritici-repentis causes tan spot, a major disease of wheat, throughout the world. The proteinaceous effector ToxA is responsible for foliar necrosis on ToxA-sensitive wheat genotypes. The single copy ToxA gene was deleted from a wild-type race 1 P. tritici-repentis isolate via homologous recombination of a knockout construct. Expression of the ToxA t...

ABSTRACT The work presented here is the first major study to analyze the genetic diversity within the worldwide population of the economically important wheat pathogen Pyrenophora tritici-repentis. The genetic structure of field populations of P. tritici-repentis was determined using amplified fragment length polymorphism markers along with sequence data from the internal transcribed spacer reg...

Tan spot (TS), caused by the fungus Pyrenophora tritici-repentis (Died) Drechs, is an important foliar disease of wheat and has become a threat to world wheat production since the 1970s. In this study a globally diverse pre-1940s collection of 247 wheat genotypes was evaluated against Ptr ToxA, P. tritici-repentis race 1, and stem rust to determine if; (i) acquisition of Ptr ToxA by the P. trit...

Tan spot, caused by Pyrenophora tritici-repentis, is an economically important foliar disease of wheat in Kazakhstan. Population structure the pathogen changes every year due to climate change. This study aimed characterize race P. tritici-repentis isolates recovered from south and north Kazakhstan, identify tan spot resistance host genotypes based on phenotypes molecular screening. Virulence p...

A fungus Pyrenophora tritici-repentis induces tan spot of wheat which is a foliar disease that causes yield loss to wheat crops worldwide. In this study, a new, simple and non-costly technique was performed to produce the sexual stage of this fungus in culture, within 9 weeks using wheat straw. This protocol will be helpful to researchers studying the biology of sexual stage development, diseas...

The wheat Tsn1 gene on chromosome 5B confers sensitivity to a host-selective toxin produced by the pathogens that cause tan spot and Stagonospora nodorum blotch (SNB) known as Ptr ToxA and SnToxA, respectively (hereafter referred to as ToxA). A compatible Tsn1-ToxA interaction is known to play a major role in conferring susceptibility of hexaploid (common) wheat to SNB. However, a recent study ...

Alternative hosts increase the difficulty of disease management in crops because these alternate hosts provide additional sources of primary inoculum or refuges for diversity in the pathogen gene pool. Agropyron cristatum (crested wheatgrass), Bromus inermis (smooth bromegrass), Pascopyrum smithii (western wheatgrass), Stipa viridula (green needlegrass), and Thinopyrum intermedium (intermediate...

Rye (Secale cereale L.) serves as an alternative host of Pyrenophora tritici-repentis (PTR) the cause of tan spot on wheat. Rye is cultivated as a forage or cover crop and overlaps with a significant portion of wheat acreage in the U.S. northern Great Plains; however, it is not known whether the rye crop influences the evolution of PTR races. We evaluated a global collection of 211 rye accessio...

Tan spot caused by the fungus Pyrenophora triticirepentis is a serious disease of wheat, which is on increase in recent years in Mediterranean region. In the field this fungus produces a diamond-shaped necrotic lesions with a yellow halo on wheat foliage. The objective of this study was to characterize and compare several monospore isolates of P. tritici-repentis collected from different infect...