Acta Scientiarum Polonorum
Silvarum Colendarum Ratio et Industria Lignaria

Introduction. Porodaedalea pini (Brot.) Murrill often occurs in Scots pine stands, whereit is a constant threat and causes significant losses of wood raw material.

Objective. It is difficult to clearly determine why in some regions of the country the fungus is more often found, therefore it was decided to determine the effect of temperature on the distribution of pine wood by Porodaedalea pini. This experiment was also used to determine the change in pH of the wood.

Methods. Five variants of the experiment were used: 1. temperature 21°C in total darkness; 2. temperature 21°C in day/night conditions; 3. temperature 14°C in total darkness; 4. temperature 4°C in total darkness; 5. natural termo-period (field conditions) from March 1 to August 31.

Results. In all the variants studied, the fungus caused the decomposition of wood. It was shown that the result of the experiment was influenced most by the thermal and light factors than the individual characteristics of the fungal isolates. By spreading the wood, the fungus lowered the pH. The thermal conditions prevailing  in Poland with an average annual temperature of 6–8°C favour the development of the P. pini, which is able to develop at a temperature of 4°C. Taking into account the distribution of tree stands in Poland with a high degree of infection by P. pini, it can be assumed that the temperature does not affect this state of affairs.