Exploring relationships among grapevine chemical and physiological parameters and mycobiome composition under drought stress
Improving our knowledge on biotic and abiotic factors that influence the composition of the grapevine mycobiome is of great agricultural significance, due to potential effects on plant health, productivity, and wine characteristics. Among the various environmental factors affecting the morphological, physiological, biochemical and molecular attributes of grapevine, drought stress is one of the most severe, becoming increasingly an issue worldwide.
In the present study we assessed the influence of water deficit and scion cultivar on the diversity and composition of fungal communities and chemical characteristics of the berries and leaves. Based on physiological parameters (pre-dawn water potential and gas-exchange) a sampling area was designed in the Eger Wine Region, Hungary, affected by moderate drought stress. We generated DNA metabarcoding data, and statistically compared the richness, relative abundance, and composition of several functional groups of fungi in two cultivars (Vitis vinifera cv. Furmint, and cv. Kadarka), which are partly explained by measured differences in chemical composition of leaves and berries and physiological traits of leaves. The richness and relative abundance of fungal functional groups statistically differ among berry and leaf, and control samples compared to those under drought stress, but less so among cultivars. We also detected cultivar-level and stress-related differences in the macro- and microelement content of the leaves, and in acidity and sugar concentration of berries. Finally, the correlation between fungal community composition and physiological variables in leaves is noteworthy, and merits further research to explore causality. Our findings offer novel insights into the microbial dynamics of grapevine considering drought stress, plant chemistry and physiology, with implications for viticulture.
This project was supported by the Research and development to improve sustainability and climate resilience of viticulture and oenology at the Eszterházy Károly Catholic University (TKP2021-NKTA-16).
Issue: ICGWS 2023
1Food and Wine Research Institute, Research and Development Center, Eszterházy Károly Catholic University, Leányka u. 6, 3300 Eger, Hungary
2ELKH–EKKE Lendület Environmental Microbiome Research Group, Eszterházy Károly Catholic University, Leányka u. 6, 3300 Eger, Hungary
3Doctoral School of Environmental Sciences, Hungarian University of Agricultural and Life Sciences, Páter K. u. 1, 2100 Gödöllő, Hungary
4Institute for Viticulture and Enology, Faculty of Natural Sciences, Eszterházy Károly Catholic University, Leányka u. 6, 3300 Eger, Hungary