Restoration of urban agriculture soil by autochthonous fungal biodiversity
Florio Furno M, Tramontini M, Gaggero E, Rigoletto M, Fabbri D, Malandrino M, Calza P, Varese GC, Spina F
Applied Microbiology and Biotechnology
Urban Farm DB summary
Polycyclic aromatic hydrocarbons (PAHs) persist in soil and resist common recovery strategies, which matters for urban agriculture because such sites are highly exposed to varied pollution sources — and because that exposure shapes how urban growing is perceived. This study examined the fungi already present in polluted soil intended for urban agriculture, aiming to build an active microbial consortium able to transform the pollutants and lower site toxicity. The mycobiota was dominated by Ascomycota; among 28 isolated taxa across 16 genera, Aspergillus, Scedosporium, Trichoderma and Fusarium were the most abundant. Isolates differed markedly, between and within species, in their ability to grow in the presence of low- and high-molecular-weight PAHs, and some produced biosurfactants. Combining this with the ability to grow on carriers, six fungi were selected for in situ soil remediation, and biostimulation was compared with bioaugmentation using strains in co-culture. The best results came from a consortium that also showed high tolerance to high-molecular-weight PAHs. Chronic ecotoxicity testing showed no effect on Eisenia fetida except under biostimulation, which produced a 44 per cent decrease in toxicity. A mix of millet and canary seeds worked as an efficient fungal carrier.