Exploring the Diversity and Aromatic Hydrocarbon Degrading Potential of Epiphytic Fungi on Hornbeams from Chronically Polluted Areas

Abstract

Plants can ‘catch’ and mitigate airborne pollutants and are assisted by fungi inhabiting their leaves. The structure and function of the fungal communities inhabiting the phyllosphere of hornbeam trees growing in two chronically polluted areas, the oilfield of Bóbrka and the city center of Warsaw, were compared to the ones growing in one nature reserve, the Białowieża National Park. Fungi were isolated and characterized both phylogenetically and functionally for their potential role in air pollution mitigation. Both culture-dependent (e.g., enzyme assays and tolerance tests) and culture-independent methods (e.g., ITS and shotgun sequencings) were used. Furthermore, the degradation potential of the fungi was assessed by gas chromatography mass spectrometry (GC-MS). Shotgun sequencing showed that the phyllosphere fungal communities were dominated by fungi belonging to the phylum Ascomycota. Aureobasidium was the only genus detected at the three locations with a relative abundance ≥1.0%. Among the cultivated epiphytic fungi from Bóbrka, Fusarium sporotrichioides AT11, Phoma herbarum AT15, and Lophiostoma sp. AT37 showed in vitro aromatic hydrocarbon degradation potential with laccase activities of 1.24, 3.62, and 7.2 μU L−1, respectively, and peroxidase enzymes with activities of 3.46, 2.28, and 7.49 μU L−1, respectively. Furthermore, Fusarium sporotrichioides AT11 and Phoma herbarum AT15 tolerated exposure to airborne naphthalene and benzene. Lophiostoma sp. AT37 was the most tolerant to exposure to these pollutants, in line with being the best potential aromatic hydrocarbon degrader isolated in this study.

Leaf-Associated Epiphytic Fungi of Gingko biloba, Pinus bungeana and Sabina chinensis Exhibit Delicate Seasonal Variations

“…At the genus level, the core fungal microorganisms in this study included Phoma , Cladosporium , Epicoccum and Alternaria , which were found to be dominant in previous studies of other plant leaf-associated fungal communities [ 45 , 46 , 47 , 48 ]. The previous study using culture-dependent methods found that Alternaria , Cladosporium , Fusraium and Phoma were the main epiphytic fungi on Hornbeams [ 49 ], which were both included in our study with culture-independent methods. Furthermore, studies have shown that Epicoccum is an important endophytic fungus involved in the production of secondary metabolites, and some species, such as E. nigrum , can act as biocontrol agents to promote plant growth and resist brown-rot pathogen [ 50 , 51 ].…”

Quercus ilex Phyllosphere Microbiome Environmental-Driven Structure and Composition Shifts in a Mediterranean Contex

“…It is now well known how the plant genotype, its immune system, and its phenotypic features determine the shaping of phyllosphere epiphytic communities found on leaves, mediated by the presence and production of exudates and specific aspects of leaf topology [21]. In turn, the microbiome affects plant physiology by mediating plant responses to biotic and abiotic stresses or degrading organic pollutants [18,19,21,22]. Changes in the biodiversity and abundance of the phyllosphere microbiome communities have been observed when external environmental pressures occur [18][19][20][23][24][25].…”

Soil Fungi Resistant to Organic Pollutants as a Potential Solution for Air Biofiltration

“…After bacteria, fungi belong to the most abundant rhizosphere microorganisms, along with protozoa and algae as well [24]. It appears that due to their strong association with plants, some telluric fungi posse great ability to eliminate aromatic hydrocarbons [25], and the plants their self are also contributing to the removal of these compounds [25], along with their epiphytic fungi as well [26]. Even more, simultaneously involvement of multiple microorganisms leads to a cooperative degradation process [27], while many of them became interdependent [21].…”