Lo scopo del lavoro e' valutare, mediante la tecnica del DNA metabarcoding, la diversità fungina presente in campioni aerodispersi utilizzati per il monitoraggio ambientale e della salute umana, di routine analizzati solo mediante ispezione microscopica. I risultati dell'analisi molecolare sono stati confrontati con quelli ottenuti mediante quella al microscopio, con particolare attenzione all'identificazione di patogeni umani e vegetali e di specie aliene invasive. Il DNA metabarcoding si è rivelato un promettente approccio per incrementare la qualità e la sensibilità del monitoraggio aerobiologico.

Abstract

Fungal spores and mycelium fragments are particles which become and remain airborne and have been subjects of aerobiological studies. The presence and the abundance of taxa in aerobiological samples can be very variable and impaired by changeable climatic conditions. Because many fungi produce mycotoxins and both their mycelium fragments and spores are potential allergens, monitoring the presence of these taxa is of key importance. So far data on exposure and sensitization to fungal allergens are mainly based on the assessment of few, easily identifiable taxa and focused only on certain environments. The microscopic method used to analyze aerobiological samples and the inconspicuous fungal characters do not allow a in depth taxonomical identification. Here, we present a first assessment of fungal diversity from airborne samples using a DNA metabarcoding analysis. The nuclear ITS2 region was selected as barcode to catch fungal diversity in mixed airborne samples gathered during two weeks in four sites of North-Eastern and Central Italy. We assessed the taxonomic composition and diversity within and among the sampled sites and compared the molecular data with those obtained by traditional microscopy. The molecular analyses provide a tenfold more comprehensive determination of the taxa than the traditional morphological inspections. Our results prove that the metabarcoding analysis is a promising approach to increases quality and sensitivity of the aerobiological monitoring. The laboratory and bioinformatic workflow implemented here is now suitable for routine, high-throughput, regional analyses of airborne fungi.