DISCUSSION
The role of the different insects species in F. circinatumspreading depends on their
bioecology. Tomicuspiniperda is the most important candidate due to its shoot-feeding
maturation behavior in the crowns of healthy pine trees (Jacobset al., 2004).Fusarium
circinatumappeared in the 3.5% of the fallen shoots bored by T. piniperda. This insect
species has also been related to some other pathogenic fungi like Leptographium wingfieldii
Morelet in North America and in Europe (Jacobset al., 2004), but it has never been reported
its relationship with the pitch canker fungus F. circinatum. The role of this bark beetle
species could be also related to forest management, thus, in the study carried out by
Långström and Hellqvist (1993) T. piniperda´s breeding galleries appeared more frequently
related to those trees that had been pruned one month before beetles´ flight than in those
that had been prune one year before. This could be an important issue to take into account
due to the relationship between pruning and pitch canker disease (Bezoset al., 2012),
although in the present study no differences were found between pruned and unpruned plot
regarding fungal diversity associated to shoots with T. piniperdafeeding gallery.