Schizophyllum commune: The main cause of dying trees of the Banja Luka arbored walks and parks

Abstract

In the frame of investigation of the main cause of dying trees of the main arbored walks (Mladena Stojanovica Aley and Park), the investigation of the presence and diversity of macrofungi in Banja Luka City were undertaken in the period 2006-2011. Relatively poor generic diversity of lignicolous (pathogenic or potentially pathogenic and saprotrophic) macrofungi with only 16 species representing this group (13 basidiomycets: Schizophyllum commune, Fomes fomentarius, Stereum hirsutum, Coriolus versicolor, Flammulina velutipes, Pseudotrametes gibbosa, Ganoderma applanatum, G. lucidum, G. adspersum, Polyporus squamosus, Meripilus giganteus, Laetiporus sulphureus, Auricu?laria auricula-judae, and 3 ascomycets: Nectria cinnabarina, Xylaria hypoxylon, X. poly?morpha) were recorded. Such a poor qualitative composition of this very important fungal group could be explained by the reduction in the number of plant species in arbored walks and alleys, as well as the reduction in the number of fungi resistant to heavy air pollution caused by nearby (1-5m) fuel combustion in engines. Although only preliminary, our results pointed to the necessity of conservation and protection of the most beautiful features of Banja Luka and its alleys and arbored walks, by undertaking the measures of curing damaged trees and treating them with fungicides in order to wipe out the epiphytia caused in more than 95% of cases (dated May 2011) by Split-gill (Schizophyllum commune), present on dead wood but also on damaged trees of Aesculus hyppocastaneum (127 trees), Tilia cordata (124 trees), Tilia platyphyllos (36 trees), Tilia argentea (40 trees), Acer negundo (20 trees), Platanus acerifolia (2 trees), Robinia pseudoacacia (3 trees), Fraxinus ornus (1 tree), Betula pendula (1 tree), Catalpa sp. (2 trees), etc. Altogether, during the last decade, around 200 trees collapsed or were sanitary cut in Banja Luka arbored walk from the Malta site to the Green bridge, a total length around 5 km. The reason for this was primarily due to Split-gill fungus and the restoration of arbored walks in the streets extremely polluted by engine fuel consumption in the zone of Mladena Stojanovica street. By analyzing the trees along the City of Banja Luka main street it could be concluded that, besides the appearance of suffocation of plants, due to wide asphalt surfaces that are located immediately next to the tree-trunks and heavy air pollution, fungi caused illnesses are the most important cause of the decline of trees. With its great adaptation to arid climate and ability to resist to the air pollution, Schizophyllum commune turned out to be the most aggressive and successful universal fungal invader of trees from old alleys, even threatening immuno?compromised human individuals. However, man and his direct or indirect impacts contrib?ute to the dying of trees much faster than the fungal pathogens in the busiest and most polluted Mladena Stojanovica street.U okviru istrazivanja glavnog uzroka odumiranja stabala banjaluckih drvoreda (Aleja u ulici Mladena Stojanovica i Parku Mladena Stojanovica), istrazivani su prisustvo i raznovrsnost lignikolnih makrogljiva u periodu 2006-2011. godine. Relativna siromasna genericka raznovrsnost lignikolnih (patogenih ili potencijalno patogenih i saprotrofnih) makrogljiva sa samo 16 vrsta koje predstavljaju ovu grupu (zabelezeno je 13 bazidiomiceta: Schizophyllum commune, Fomes fomentarius, Stereum hirsutum, Coriolus versicolor, Flammulina velutipes, Pseudotrametes gibbosa, Ganoderma applanatum, G. lucidum, G. adspersum, Polyporus squamosus, Meripilus giganteus, Laetiporus sulphureus, Auricularia auricula-judae i 3 askomicete: Nectria cinnabarina, Xylaria hipoxylon, X. polimorpha). Tako siromasan kvalitativni sastav ove veoma vazne grupe gljiva moze se objasniti redukovanjem drvoreda i aleja na mali broj biljnih vrsta, ali i smanjenjem broja gljiva otpornih na velika zagadjenja vazduha izazvana veoma bliskim izduvnim gasovima (1-5 m) koji nastaju sagorevanjem goriva u motorima. Iako preliminarni, nasi rezultati ukazuju na neophodnost ocuvanja i zastite najlepsih karakteristika Banje Luke, njenih aleja i drvoreda, na neophodnost preduzimanja mera lecenja ostecenih stabala i tretiranja fungicidima u cilju eliminacije epifitije, u vise od 95% slucajeva (od maja 2009), izazvane lignikolnom fitopatogenom gljivom Schizophyllum commune, konstatovanom na mrtvom drvetu, ali i na ostecenim stablima Aesculus hippocastaneum (127 stabala), Tilia cordata (124 stabala), Tilia platiphillos (36 stabala), Tilia argentea (40 stabala), Acer negundo (20 stabala), Platanus acerifolia (2 stabla), Robinia pseudoacacia (3 stabla), Fraxnus ornus (1 stablo), Betula pendula (1 caj), Catalpa sp. (2 stabla), itd. Sve u svemu, tokom poslednje decenije, oko 300 stabala je uginulo ili uklonjeno sanitarnom secom u banjaluckoj aleji Mladena Stojanovica od Malte do Zelenog mosta, ukupne duzine oko 4 km, usled ostecenja izazvanih prvenstveno gljivom Schizophyllum commune, tako da restauracija drvoreda duz saobracajnice koja se odlikuje veoma zagadjenim vazduhom, izazvanim unutrasnjim sagorevanjem motornih goriva postaje gotovo nemoguca misija. Analizirajuci drvece duz glavne ulice grada Banje Luke moglo bi se zakljuciti da je, pored pojave ?gusenja? biljaka, zbog velikih povrsina asfalta koje se nalaze neposredno pored stabala drveca i teskih zagadjenja vazduha, bolesti prouzrokovane gljivama su najvazniji uzrok propadanja drveca. Sa svojim izrazenim mocima adaptacije na susne klimatske uslove, i izvanredno otporan na zagadjenja vazduha, ispostavlja se da je gljiva Schizophyllum commune najagresivniji i najuspesniji univerzalni invador stabala starih banjaluckih aleja i parkova, cak preteci imunokompromitovanim osobama ljudske populacije. Nazalost, covek svojim direktnim ili indirektnim uticajima brze i uspesnije od patogenih gljiva doprinosi umiranju drveca duz najprometnije i najzagadjenije banjalucke ulice.