Attack behavior of pine bark beetles in Morocco and association with phytopathogenic fungi

الملخص EN

The biology of Tomicus piniperda and Orthotomicus erosus was studied in four regions of Morocco, corresponding to three bioclimatic zones and two varieties of maritime pine.

By using trap trees, the dates and the distribution of the attacks on the trees were defined.

The fungus species carried by the beetles were identified and the variations of their frequency were characterized.

In most regions, T.

piniperda has two periods of trunk attack: one in autumn, interpreted as due to Tomicus destruens species (1st mention in Morocco); the other in early spring, interpreted as due to T.

piniperda itself.

The autumn attacks have their highest densities in the bottom sections of the trees, while the highest attack densities were observed in the middle sections during spring.

T.

piniperda is associated w'ith Leptographium wingfieldii, a fungus already observed in Europe, but the frequency of association is much higher in Morocco.

O.

erosus had three or four periods of attacks (generations) per year, depending on the region, but the relations with the bioclimatic characteristics are not clear.

The maximum attack density of this species is located in the middle sections of the trees, but at a lower level, in the humid and sub-humid zones with the moghrebiana pine variety than in the semi-arid zone with the atlantica pine variety.

O.

erosus is associated with Ophiostoma ips, a widely distributed fungus, but the frequency of this association in Morocco is much lower than that reported in Europe with the bark beetles of the genus Ips.