Researchers have, for the first time, isolated a gene that will give wheat a
natural resistance to Septoria tritici blotch (STB, or Septoria). Septoria
is the main leaf disease of wheat in temperate regions and a major threat
for wheat production globally, capable of halving crop yields. The disease
is caused by the fungal pathogen Zymoseptoria tritici.
The gene, called Stb6, has been known for 20 years, but its mapping and
isolation took five years to complete by a research team led by Kostya
Kanyuka at Rothamsted Research and Cyrille Saintenac at the National
Institute for Agricultural Research (INRA).
Kanyuka said that the Stb6 gene is effective against only a fraction of
fungal strains, specifically those that secrete a matching protein, called
AvrStb6. The Stb6 protein somehow recognizes this fungal protein, which
leads to activation of the defense response in wheat.