Schizophyllum commune – the dominant cause of trees decay in alleys and parks in the City of Novi Sad (Serbia)

Abstract

As part of a study of the main causes of dying trees in alleys and parks in the City of Novi Sad, an investigation of the presence and diversity of macrofungi was undertaken over the period 2012-2014. The relatively poor genetic diversity of lignicolous (pathogenic or potentially pathogenic and saprotrophic) macrofungi with only 24 species representing this group (19 basidiomycets and 5 ascomycets) has been recorded. The poor qualitative composition of this important ecological group of fungi could be explained by the small number of plant species present in arbored walks and alleys, but also to the reduced number of fungi resistant to heavy air pollution caused by the close proximity of (1-5 m) fuel combustion engines. Although preliminary, these results point to the necessity of conservation and protection of the most beautiful features of The Novi Sad City - its alleys, avenues and parks - by undertaking measures of curing damaged trees and treating with fungicides in order to wipe out the epiphytia caused in more than 95% of cases by split-gill (Schizophyllum commune), found to be present on dead wood as well as damaged trees of: Tilia cordata, T. platyphyllos T. argentea, Acer negundo, A. platanoides, Aesculus hyppocastaneum, Platanus acerifolia, Fraxinus ornus, Betula pendula, Robinia pseudoacacia, Celtis australis, C. occidentalis, Catalpa speciosa, Corylus avelana, Ficus carica, Pinus silvestris, Prunus spp., Salix alba, Carpinus betulus pyramidalis, etc. Altogether, over the last decade, around 200 trees have collapsed or have been sanitary felled in alleys and parks of Novi Sad due to damage caused primarily by split-gill fungus. Thus, restoration of avenues along streets characterized by very polluted air generated by combustion engine fuel, accompanied by extreme temperatures, (from -30 °C to +45 °C), prolonged drought and heavy insolation of young plants is becoming an almost impossible mission. Analysis of trees along the streets of Novi Sad revealed that, in addition to visible suffocation of plants from heavy air pollution and wide asphalt surfaces located next to tree-trunks, illnesses caused by fungi are the dominant cause of tree decay. Because it has adapted to arid climates, and is resistant to air pollution, Schizophyllum commune turned out to be the most aggressive and successful ubiquitous fungal invader of trees in old alleys. This fungus is also an important factor threatening immune-compromised persons: there are recorded cases in the region of allergies, abscesses and inflammatory conditions caused by this basidiomycetous fungus among individuals of the human population.