Geographical Origin Has a Greater Impact on Grape Berry Fungal Community than Grape Variety and Maturation State.

Dimitrios Kioroglou,Maria C Portillo,Albert Mas,Leigh M Schmidtke,Elena Kraeva-Deloire

doi:10.3390/microorganisms7120669

Dimitrios Kioroglou, Maria C Portillo + Show 3 more

Open Access

https://doi.org/10.3390/microorganisms7120669

Copy DOI

Abstract

We used barcoded sequencing to analyze the eukaryotic population in the grape berries at different ripening states in four Australian vineyards. Furthermore, we used an innovative compositional data analysis for assessing the diversity of microbiome communities. The novelty was the introduction of log-ratio balances between the detected genera. Altogether, our results suggest that fungal communities were more impacted by the geographical origin of the Australian vineyards than grape variety and harvest time. Even if the most abundant genera were Aureobasidium and Mycosphaerella, they were ubiquitous to all samples and were not discriminative. In fact, the balances and the fungal community structure seemed to be greatly affected by changes of the genera Penicillium, Colletotrichum, Aspergillus, Rhodotorula, and Botrytis. These results were not evident from the comparison of relative abundance based on OTU counts alone, remarking the importance of the balance analysis for microbiome studies.

Highlights

The concept of “terroir,” in oenology refers to a geographic area characterized mainly by its climate, soil, and human factors that contribute to producing typical wines
Given the low number of 16S rRNA sequences per sample combined with the fact that the majority of these sequences have been identified of belonging to the genus Sphingomonas, we considered that the obtained sequences for this amplicon were not enough for a robust analysis of the bacterial community
This study used barcoded massive sequencing to analyze the effect of the grape ripening state, the vineyard region, and grape variety on the grape mycobiome

Summary

Introduction

The concept of “terroir,” in oenology refers to a geographic area characterized mainly by its climate, soil, and human factors that contribute to producing typical wines. The term “microbial terroir” is recently gaining interest in viticultural studies to indicate the importance of the vineyard microbiome composition over the regional wine typicity. Due to advances in metagenomics and the development of high-throughput sequencing (HTS) techniques, the grapevine microbiome is receiving increasing attention. Metagenomic analyses suggest that the microbial communities associated with grapes and grape must resemble the ones present on leaves [2,3] and have their source mainly in the soil and surrounding fields [4]. Grape microorganisms can be transferred to the winery where, they may affect wine chemical composition and influence its quality, even at the regional scale [5,6,7,8]

Methods

Results

Discussion

Conclusion