terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 A comprehensive study on the effect of foliar mineral treatments on grapevine microbiota, flavonoid gene expression, and berry composition

A comprehensive study on the effect of foliar mineral treatments on grapevine microbiota, flavonoid gene expression, and berry composition

Abstract

Recently, foliar treatments with mineral-based compounds have shown positive effects on grapevine production by protecting grape from thermal excesses and reducing the decoupling between technological and phenolic maturity caused by climate change.  Unraveling the effect of mineral particle applications on grape-associated microbes is pivotal for successful wine processing, due to the influence of the microbiota on wine composition and stability. To our knowledge, this is the first work that comprehensively studied the effects of kaolin and chabasite-rich zeolitites treatments on grape-related microorganisms (by real-time PCR quantification of total fungi, Hanseniospora uvarum, Metschnikowia pulcherrima, plant-associated bacteria and lactic acid bacteria), the expression of genes related to the flavonoid biosynthesis (PAL1, CHS1, F3H2, DFR, LDOX, UFGT, MYBA1, GST4, FLS4 genes) and the berry composition (°Brix, pH, acidity and anthocyanin concentrations) in cv. Sangiovese during ripening in two growing seasons (2019 and 2020). Here, we found both mineral treatments to cause elicitation of several flavonoid-related genes and development of higher anthocyanin concentration in berries without an alteration of the final technological maturity of grapes. Fungal and bacterial levels fluctuated over the growing season. Interestingly, we observed that in a climatic season characterized by mild temperatures and high rainfall (2020), no effect of the treatments was observed on the microorganisms analysed. Conversely, in a more stressful year (2019), chabasite-rich zeolitites treatments induced an increase in total fungi and H. uvarum populations 48h upon the second spray. Additionally, at the same sampling date, we observed higher M. pulcherrima population in kaolin treated berries in respect to control ones. However, treated grapes did not show significant differences on microbial composition at harvest. These results support the use of foliar mineral treatments to ameliorate anthocyanins concentration in grapes berries, protecting them from excessive heat without altering their native microbiota.

DOI:

Publication date: October 3, 2023

Issue: ICGWS 2023

Type: Article

Authors

Daniela Sangiorgio1, Gabriele Valentini1, Chiara Pastore1, Gianluca Allegro1, Davide Gottardi1, Francesca Patrignani1, Francesco Spinelli1, Ilaria Filippetti1

1Department of Agricultural and Food Sciences (DISTAL), University of Bologna, Viale Fanin, 46, 3rd floor, 40127 Bologna, Italy

Contact the author*

Keywords

kaolin, chabazite-rich zeolitite, bacteria, fungi, grape

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Oenological compatibility of biocontrol yeasts applied to wine grapes 

Antagonistic yeasts applied to wine grapes must be compatible with the thereafter winemaking process, avoiding competition with the fermentative Saccharomyces cerevisiae or affecting wine flavour. Therefore, fifteen epiphytic yeasts (6 Metschnikowia sp., 6 Hanseniaspora uvarum, 3 Starmerella bacillaris) previously selected for its biocontrol ability against Alternaria on wine grapes were evaluate for possible competition with S. cerevisiae by the Niche Overlap Index (NOI) employing YNB agar media with 10 mM of 17 different carbonate sources present in wine grapes (proline, asparagine, alanine, glutamic acid, tirosine, arginine, lisine, methionine, glicine, malic acid, tartaric acid, fructose, melibiose, raffinose, rhamnose, sucrose, glucose).

Study of Spanish wine sensory analysis data over a 3-year period

This study presents an investigation based on sensory analysis data of Spanish wines with geographical indications collected over a three-year period. Sensory analysis plays a crucial role in assessing the quality, characteristics, and perception of wines. The trained tasting panel at Dolmar Laboratory, accredited for objective sensory evaluation of wines since 2016, has been tasting over 5000 wines. However, it is since 2021, when a computer application for tastings was developed, that the digitalization of data allows for detailed statistical analysis of the results.

Options to replace or reduce the sulphite content in Tannat red wines produced with minimal intervention

Several Uruguayan wineries have begun to produce wines with minimal intervention, to increase the sustainability of their vineyards and wines. These wines are characterized by the minimum intervention in the management of the vineyard, its harvest, vinification, conservation and aging1,2. Sulfur dioxide (SO2) is not used or is used in reduced doses, although chitosan can be substituted or supplemented1. The objective of this research is to evaluate SO2 reduction or replacement options adapted to the production of Tannat red wines with minimal intervention. Vinification of the Tannat grapes with autochthonous yeasts (LN) was carried out during the 2023 vintage.

Influence of polysaccharide extracts from wine by-products on the volatile composition of sparkling white wines

In the production of sparkling wines, during the second fermentation, mannoproteins are released by yeast autolysis, which affect the quality of the wines. The effect of mannoproteins has been extensively studied, and may affect aroma and foam quality. However, there are no studies on the effect of other polysaccharides such as those from grapes. Considering the large production of waste from the wine industry, it was proposed to obtain polysaccharide-rich extracts from some of these by-products[1].

Extreme vintages affect grape varieties differently: a case study from a cool climate wine region

Eger wine region is located on the northern border of grapevine cultivation zone. In the cool climate, terroir selection is one of the foundations of quality wine making. However, climate change will have a significant impact on these high value-added vineyards. This study presents a case study from 2021 and 2022 with the investigation of three grape varieties (Kadarka, Syrah, Furmint). The experiment was conducted in a steep-sloped vineyard (Nagy-Eged hill) with a southern exposure.