Investigating the impact of pedoclimatic conditions on the oenological performance of two red cultivars grown throughout southern Italy

Abstract

The cultivated grapevine, Vitis vinifera subsp. vinifera, possesses a rich biodiversity with numerous varieties. Each variety adapts differently to varying pedoclimatic conditions, which greatly influence the terroir expression of wine regions. These conditions impact vine growth, physiology, and berry composition, ultimately shaping the unique characteristics and typicity of the wines produced. Nowadays, the potential of the different adaptation capacities of grape varieties has not yet been thoroughly investigated. We addressed this issue by studying two grape varieties, Aglianico and Cabernet Sauvignon, in two different pedoclimatic conditions of Southern Italy. We evaluated and compared the effect of different pedoclimatic conditions on plant physiology, the microbial quality of grapes using Next-Generation Sequencing (NGS) technology, the expression trends of key genes in ripe berries and the concentration of phenolic compounds in grapes and wines by HPLC-MS, HPLC-DAD, NMR and spectrophotometric analyses. Metabolomic and microbiome data were integrated with quantitative gene expression analyses to examine varietal differences and plasticity of genes involved in important oenological pathways. The data collected showed that the phenotypic response of studied grapes in terms of vigor, production, and fruit quality is strongly influenced by the pedoclimatic conditions and, in particular, by soil physical properties. Furthermore, Aglianico grape variety was more influenced than the Cabernet Sauvignon by environmental conditions. In conclusion, the obtained findings not only reinforce the terroir concept and our comprehension of grape’s ability to adapt to climate variations but can also have implications for the future usage of grape genetic resources.

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

“…From the taxonomy classification 3 phyla , 17 classes, 45 orders, 96 families, 122 genera and 172 species were identified. In general, the analysis of fungal community confirmed our previous findings ( Iorizzo et al, 2023 ). In fact, Ascomycota remained the most abundant phylum , representing 87.9% ± 9.4% of total reads, followed by Basidiomycota 11.8% ± 9.3% and Chytridiomycota 0.02% ± 0.08% in all analyzed samples.…”

“…In the present study, we used both HTS and multivariate data analysis to investigate the fungi community structure of grape samples collected in three different vineyards located in Campania, Molise and Sicily regions (Southern Italy) and belonging to two red grape varieties (Aglianico and Cabernet). In general, the descriptive approach through relative abundance analysis confirmed what we already found in our previous study ( Iorizzo et al, 2023 ), but in the present research, new information is derived from the addition of new samples from the Campanian vineyard. Moreover, the statistical approach used furnished new important information on the structure of fungal communities as related to vineyard location and grape variety.…”

“…and devoted to the production of Aglianico and Cabernet were also withdrawn in the same period. For each farm and for each cultivar, 30 clusters were harvested from different positions of the vineyard and from random positions on the plant to ensure the representation of the entire vineyard as previously described ( Iorizzo et al, 2023 ). Briefly, at least ten berries were randomly selected from different parts of the cluster, avoiding those with visible damage and/or signs of pathogen infection, and pooled with berries from the other plants.…”

“…Fungal community composition was analyzed by a culture-independent approach using next generation sequencing (NGS), as described in a previous study ( Iorizzo et al, 2023 ). Total genomic DNA was extracted using the Stool DNA Isolation Kit (Norgen, Biotek Corp., Thorold, ON, Canada) according to the manufacturer’s instructions.…”

“…As a result, the application of HTS methods for in-depth assessment of the grape and wine microbiome has increased in recent years ( Salvetti et al, 2016 ; Morgan et al, 2017 ; Dissanayake et al, 2018 ; Kamilari et al, 2021 ). In a previous study we already assessed the impact of pedoclimatic conditions on the enological performance of two red cultivars grown throughout Southern Italy ( Iorizzo et al, 2023 ). In this study, we obtained new information by adding other wine-grape samples of two cultivars (Cabernet and Aglianico) to determine relationships between spatial proximity and fungal composition through amplicons sequencing of the internal transcribed spacer (ITS2) region using a HTS approach combined with bioinformatics.…”