Varietal susceptibility (Apple powdery mildew)

Apple varieties vary in susceptibility to mildew.

  • Cox, Idared, Golden Delicious, Gala, Fiesta, Jonagold, Elstar are very susceptible.
  • Bramley, Worcester, Saturn are moderately susceptible and Discovery and Grenadier have very low susceptibility to mildew.
  • Susceptibility to mildew based on mildew incidence alone can be misleading, e.g. the incidence of mildew on Golden Delicious can be higher than on Cox.
  • However, Golden Delicious appears to be more tolerant of mildew than Cox and therefore the disease would have a much lower effect on yield and quality.
  • Such information, however, can only be obtained from crop loss studies conducted over several seasons.