New data on the fungus species composition of spruce trunk сancer

Abstract

The composition of canker mycobiota on spruce trunks in the Lisinsky forestry (Leningrad region) was studied. Small cancers or parts thereof were placed in a humid chamber. Fungi were identified by morphological features. The most common fungi were Sorocybe resinae (Fr.) Fr. and Penicillium glaucoalbidum (Desm.) Houbraken & Samson. The occurrence of S. resinae was 75.9%. The fungus developed in the surface layers of the dried resin, and in the absence of resinification, this fungus was not observed. It can be concluded that the fungus S. resinae is an almost integral component of the mycobiota of a resinous cancer on a spruce trunk in the Leningrad Region. Until now, the fungus P. glaucoalbidum has been registered in Russia only as a saprotroph. The performed experiments have shown the presence of weak pathogenic properties in this species. The high occurrence of P. glaucoalbidum (41.4%) allows us to consider this fungus as a regular participant in spruce trunks canker. An experiment was laid to test the species isolated in pure culture (P. glaucoalbidum and Oidiodendron sp.) as possible causative agents of trunk cancer. In the forest stand, 20 trunks of spruce trees were inoculated with the fungal cultures. The cultures stimulated the secretion of resin, without causing the growth of necrosis beyond the boundaries of the inflicted wound. It has been suggested that a more thorough study of biota of necrosis-cancerous formations and especially its non-pathogenic part will allow us to more accurately understand the nature of this phenomenon.