• Erisyphe graminis;
  • hyphal development;
  • mutant lines resistance;
  • thaumatin-like gene;
  • Triticum aestivum

Mutant lines of the wheat (Triticum aestivum) cultivar Hobbit ‘sib’, produced by irradiation with fast neutrons, were evaluated for their response to powdery mildew (Erisyphe graminis f.sp. tritici) at various growth stages to identify and characterize resistance. Two mutants, I3-54 and I3-48, were found to be significantly more resistant than Hobbit ‘sib’, with the resistance being expressed in both seedlings and adult plants. Fungal hyphal development was slower in both the mutants than in Hobbit ‘sib’ between 18 and 24 h after inoculation, and fewer haustoria were formed in the mutants, particularly in I3-54, 72 h after inoculation. Constitutive expression of a thaumatin-like protein gene was detected in both I3-48 and I3-54 but not in Hobbit ‘sib’.