Microbial diversity of grape berries

Botrytis cinerea, a well-known grapevine pathogen, has more than 1200 host plants causing grey rot in grapevine berries. However, it can also result in a desirable phenomenon called noble rot under specific microclimate conditions. An extraordinary demonstration of this natural process can be observed in the creation of aszu wines within Hungary's Tokaj wine region. Beside B. cinerea other fungi and yeasts are involved in the secondary metabolic development of the grape berry which contributes to the sensory and analytical characterization of noble rot wines. In our study, we generated DNA metabarcoding data from healthy, noble rot and grey rot berries in 3 different vineyards from the Tokaj wine region from Furmint cultivar. We analyzed the fungal microbiome of the collected samples and characterized the location by its microbial ecology. The berry samples were collected in 2022 in the Betsek (B) (48.188126, 21.317584), Szent Tamas (S) (48.20108, 21.30017) vineyards, and the vineyards of Uragya (U) (48.19981, 21.27400) which are situated at the border of Mad village (Tokaj wine region, Hungary). On 17 October 2022, grape berries of varying rot types were collected from a Furmint cultivar with Teleki-Kober 5BB rootstock. At the time of sampling, all phases were observed concurrently, including healthy berries (H, or phase I), noble rot berries (NR, or phase IV), and grey rot berries (GR, or phase VI). The different berry types were classified on the basis of visual and textural parameters (Hegyi-Kalo et al., 2020; Naegele, 2018) as follows:i) Healthy berries are whole green or yellow-green berries without any lesion spots with a completely The healthy stem joint is characterised by a lack of lesions and a green or yellow-green colouration. In contrast, the berries exhibiting noble rot display a brown or purple-brown hue and a shrivelled appearance. Additionally, grey rot berries exhibit a distinct colouration from that of the NR berries, ranging from brown to light brown. They also display a dry, hard, or completely degraded texture, accompanied by advanced berry skin degradation, which may manifest as leakage onto the skin. Five biological replicates were collected from the berries, stored aseptically in 50 ml tubes, and quenched in liquid nitrogen at the vineyard.