Different factors are operative in shaping the epiphytic grapevine microbiome across different geographical scales: Biogeography, cultivar or vintage?

Abstract

Introduction:The composition of the grapevine microbiome is controlled by a range of factors all contributing to the establishment of microbial terroir. Most studies have focused on the grape must microbiome, while less is known about the assemblage mechanisms of the epiphytic grapevine microbiome. We aimed to disentangle the role of geographic location, cultivar and vintage on the composition of the epiphytic fungal and bacterial communities of grapevine: within (regional scale) and across (national scale) viticultural zones in Greece. We hypothesised that: (i) the influence of all three factors varies at different geographical scales; (ii) fungi and bacteria respond differently to the factors shaping the grapevine microbiome. Materials and Methods:We analysed leaves and berries collected from Greek cultivars (i) Vidiano and Agiorgitiko located in three geographically distant regions (from 100 to >600 km), (ii) Roditis and Sideritis from different terroir units of the viticultural zone of Aigialeia.Results: Amplicon sequencing analysis identified strong regional signatures on the epiphytic microbiome across viticultural zones, whereas cultivar becomes a strong determinant at the viticultural zone scale. Fungal communities were more responsive to all studied factors compared to bacterial communities. Differential abundance (DA) analysis identified dominant fungal (Alternaria, Cladosporium, Nigrospora, Aureobasidium, Vishniacozyma) and bacterial (Sphingomonas, Masillia, Streptococcus, Staphylococcus, Enterobacterales) amplicon sequence variants (ASVs) exhibiting geographical and cultivar-specific patterns. Conclusion: Our data suggest that different factors are operative in shaping the epiphytic grapevine microbiome at different geographical scales with bacterial and fungal communities showing different responses to the tested structural factors.

Diversity of fungal communities on Cabernet and Aglianico grapes from vineyards located in Southern Italy

“…In fact, both PCoA and sPLS-DA analyses showed that samples are mainly grouped according to the VL ( Figure 5 ). These results are consistent with those reported in other studies where it was demonstrated that the diversity of the microbial community is influenced by geographical location of vineyards ( Bokulich et al, 2014 ; Mezzasalma et al, 2017 ; Kioroglou et al, 2019 ; Papadopoulou et al, 2022 ; Kazou et al, 2023 ). Similar results were also obtained by other authors who have reported that VL has a greater impact on the fungal community than the state of ripeness ( Kioroglou et al, 2019 ).…”

Pruning Wound Protection Products Induce Alterations in the Wood Mycobiome Profile of Grapevines

“…The geographical location of vineyards is known to be a strong predictor of fungal diversity in multiple grapevine organs [71][72][73][74], even if it remains unclear to what extent other parameters, such as the application of plant protection products, grapevine age and cultivar, contribute to observed differences. Despite this limitation, Bekris et al (2021) reported significant differences in the wood mycobiome profile in Greek viticultural areas [73], and Martinez-Diz et al (2020) found highly significant differences in alpha and diversity when comparing one-year-old canes in Spanish vineyards [63].…”

“…Grapevine genotype has been reported to influence the mycobiome profile in the rhizosphere of mature but not young vineyards [74], and it is variably (strong, weak or non-significant) correlated with fungal communities at phyllosphere level [71,72,75]. Differences in the microbial composition of rootstocks have been reported in multiple studies [76][77][78], although they seem to mostly concern individual taxa abundance rather than community indices.…”

Vineyard practices reduce the incidence of Aspergillus spp. and alter the composition of carposphere microbiome in grapes (Vitis vinifera L.)

“…Grape products account for a significant portion of global agricultural production, with the total area covered by vineyards exceeding seven (7) million hectares in 2018 (FAO-OIV, 2019). Grapevine and, in particular, grape berries support a diverse epiphytic microbial community (collectively called carposphere microbiome) whose composition shows strong regional patterns, and it is affected by cultivar., vintage, and agronomic practices (Bokulich et al, 2013;Papadopoulou et al, 2022). The grape carposphere microbiome encompasses microorganisms with a key role in downstream vinification processes (Bokulich et al, 2016;Liu et al, 2020), but also carries beneficial and pathogenic microorganisms (Pantelides et al, 2015) whose interaction with each other and their host determine grapevine health and productivity (Bettenfeld et al, 2022).…”