查看文章

We recently showed that the wheat pathogen Stagonospora nodorum produces proteinaceous host‐selective toxins (HSTs). These toxins include SnTox1 as well as SnToxA, a HST first identified from Pyrenophora tritici‐repentis that was implicated in a very recent horizontal gene transfer event from S. nodorum to P. tritici‐repentis. Compelling evidence implicating SnToxA and SnTox1 in disease development has been obtained. Here, we report the partial purification and characterization of a third HST designated SnTox2, as well as the genetic characterization of the corresponding host‐sensitivity gene. SnTox2 was protease sensitive and is estimated between 7 and 10 kDa in size. Sensitivity to SnTox2 was conferred by a single dominant gene designated Snn2, which mapped to the short arm of wheat chromosome 2D. Genetic analysis of reaction to conidial inoculations in a segregating wheat population …