• 1
    Inoculations with N. galligena on unwounded shoots of apple show that canker infections through leaf scars may be initiated in October and April but not in November and January. Shoots sprayed before inoculation with a Bordeaux-casein-oil mixture gave a much lower proportion of infection than those unsprayed.
  • 2
    Inoculations with N. galligena on pruning cuts showed that freshly made pruning cuts on apple shoots are susceptible to canker infection throughout the dormant season. Pruning cuts made during autumn and winter acquire a natural immunity to infection within 2 months.
  • 3
    Several wound sealing materials applied to pruning cuts failed to give protection from canker when the treated surfaces were inoculated with N. galligena. The most promising wound protectant tested was a mixture of monohydrated copper sulphate, hydrated lime and linseed oil.