«Phaeomoniella chlamydospora»-Grapevine Interaction : Histochemical Reactions to Fungal Infection

Abstract

Histochemical reactions of one-year-old potted micropropagated vines (rootstock 1103 Paulsen) to inoculation
with Phaeomoniella chlamydospora were studied. Microscopic examination of the vine wood showed that the
fungus spread through the wood tissue, albeit slowly. Starting from the roots it required nine months to colonise the
first 20-25 cm of the grapevine stems. The slow spread of P. chlamydospora is thought to be due to the defence
response initiated by the vines: production of tyloses, including accumulation of phenols in the vessels and adjacent
tissue, and the deposition of unidentified defence-response substances, probably stilbene-like substances from the
cell-wall surrounding the infection