Terroir 2020 banner
IVES 9 IVES Conference Series 9 Terpenoid profiles and biosynthetic gene expression pattern in Asti DOCG white muscat grapes at ripening as affected by different canopy management protocols

Terpenoid profiles and biosynthetic gene expression pattern in Asti DOCG white muscat grapes at ripening as affected by different canopy management protocols

Abstract

Aim: The main goal of this study was to find an efficient canopy management to limit the high temperature-related aroma losses of White Muscat grapes, and consequently to preserve the quality standards of Asti DOCG wines.

Methods and Results: Four different strategies have been tested in two vineyards of the Asti DOCG production area: pre-flowering leaf removal (m1), post-berry set leaf removal (m2), leaf removal at veraison (m3), and clusters thinning (m4). Control vines (m0) did not receive any thinning or defoliation. Grapes were collected at four time points: seven days before the commercial harvest, at the commercial harvest scheduled for “Asti spumante” wine, at the commercial harvest scheduled for “Moscato” wine and overripening. Free and glycosylated terpenoids content (GC-MS) as well as the expression of key genes involved in terpenoids biosynthesis and metabolism (RT-qPCR) were analysed separately in skin and pulp. The results revealed a peak of volatile accumulation, which occurred early and late throughout the sampling times. The treatments m3 and m4 were, in general, those more effective in enhancing the aroma profiles in both tissues analysed. Correspondingly, in these grapes, specific genes, such as VvDXS3 and VvGT14 resulted up-regulated. Other genes, such as VvHDR, showed different expression pattern resulting, in general, more expressed in pulp than skin, regardless the applied treatment.

Conclusions:

Based on these preliminary trials carried out in a specific production area of White Muscat, it seems that m3 and m4 treatments had a significant effect on the volatile’s accumulation in both grape skin and pulp. m1 treatment resulted to be the less effective in inducing changes in the aroma profile and the terpenoid biosynthetic pathway.

Significance and Impact of the Study: Moscato d’Asti DOCG is one of the most characteristic enological products of Piemonte (North-West Italy) wine grapes-growing area. It comes exclusively from White Muscat grapes which are exalted by the climatic and geographical conditions of the production area. Indeed, the interactions between vine and environment, limestone terrain and micro-climate typical of hilly zones leads to a characteristic fruity and sweety aroma. The characteristic aroma of Muscat wine is attributed to the presence of specific terpenoids, mainly linalool, nerol, geraniol, trans-piran linalool oxide and citronellol. The grapevine terpenoids pathway is strongly regulated by endogenous and environmental factors and among them, temperature and light exposure plays a crucial role. As recently observed, the content of these compounds is strongly decreasing due to the increasing temperatures. Higher temperature during the growing season is forcing growers to find ways to reliably control grape composition preserving the typical aroma of Asti DOCG wines. The present study could offer important information to address grower’s choice in term of canopy management that are better suited to the changing climate.

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

Margherita Modesti1*, Ron Shmulevitz, Stefano Brizzolara1, Daniele Eberle2, Guido Bezzo2, Pietro Tonutti1

1Life Sciences Institute, Scuola Superiore Sant’Anna, Piazza Martiri della Libertà 33, 50127 Pisa, Italy
2Consorzio per la Tutela dell’Asti DOCG. Piazza Roma 10, 14100 Asti, Italy

Contact the author

Keywords

Canopy management, Moscato d’Asti DOCG, terpenoid content and biosynthesis, climate change

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Analysis of Cabernet Sauvignon and Aglianico winegrape (V. vinifera L.) responses to different pedo-climatic environments in southern Italy

Water deficit is one of the most important effects of climate change able to affect agricultural sectors. In general, it determines a reduction in biomass production, and for some plants, as in the case of grapevine, it can endorse fruit quality. The monitoring and management of plant water stress in the vineyard

Climate change impacts: a multi-stress issue

With the aim of producing premium wines, it is admitted that moderate environmental stresses may contribute to the accumulation of compounds of interest in grapes. However the ongoing climate change, with the appearance of more limiting conditions of production is a major concern for the wine industry economic. Will it be possible to maintain the vineyards in place, to preserve the current grape varieties and how should we anticipate the adaptation measures to ensure the sustainability of vineyards? In this context, the question of the responses and adaptation of grapevine to abiotic stresses becomes a major scientific issue to tackle. An abiotic stress can be defined as the effect of a specific factor of the physico-chemical environment of the plants (temperature, availability of water and minerals, light, etc.) which reduces growth, and for a crop such as the vine, the yield, the composition of the fruits and the sustainability of the plants. Water stress is in many minds, but a systemic vision is essential for at least two reasons. The first reason is that in natural environments, a single factor is rarely limiting, and plants have to deal with a combination of constraints, as for example heat and drought, both in time and at a given time. The second reason is that plants, including grapevine, have central mechanisms of stress responses, as redox regulatory pathways, that play an important role in adaptation and survival. Here we will review the most recent studies dealing with this issue to provide a better understanding of the grapevine responses to a combination of environmental constraints and of the underlying regulatory pathways, which may be very helpful to design more adapted solutions to cope with climate change.

Simulating climate change impact on viticultural systems in historical and emergent vineyards

Global climate change affects regional climates and hold implications for wine growing regions worldwide. Although winegrowers are constantly adapting to internal and external factors, it seems relevant to develop tools, which will allow them to better define actual and future agro-climatic potentials. Within this context, we develop a modelling approach, able to simulate the impact of environmental conditions and constraints on vine behaviour and to highlight potential adaptation strategies according to different climate change scenarios. Our modeling approach, named SEVE (Simulating Environmental impacts on Viticultural Ecosystems), provides a generic modeling framework for simulating grapevine growth and berry ripening under different conditions and constraints (slope, aspect, soil type, climate variability…) as well as production strategies and adaptation rules according to climate change scenarios. Each activity is represented by an autonomous agent able to react and adapt its reaction to the variability of environmental constraints. Using this model, we have recently analyzed the evolution of vineyards’ exposure to climatic risks (frost, pathogen risk, heat wave) and the adaptation strategies potentially implemented by the winegrowers. This approach, implemented for two climate change scenarios, has been initiated in France on traditional (Loire Valley) and emerging (Brittany) vineyards. The objective is to identify the time horizons of adaptations and new opportunities in these two regions. Carried out in collaboration with wine growers, this approach aims to better understand the variability of climate change impacts at local scale in the medium and long term.

A predictive model of spatial Eca variability in the vineyard to support the monitoring of plant status

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Assessment of climate change impacts on water needs and growing cycle on grapevine in three DOs of NE Spain

This study assessed the suitability of grapevine growing in three DOs (Empordà, Pla de Bages and Penedès) of Catalonia (NE Spain) over the 21st century. For this purpose, an estimation of water needs and agroclimatic and phenological indicators was made. Climate change impacts were estimated at 1 km pixel resolution using temperature and precipitation projections from several general circulation models (GCM) and two climate change scenarios: RCP 4.5 (stabilization scenario) and RCP 8.5 (worst-case scenario). Potential crop evapotranspiration (following FAO procedure) and a daily water balance considering soil water holding capacity were used to estimate actual evapotranspiration of vines and, finally, water needs. Dynamics would be similar in the three DOs studied although the magnitude of impact differs. Water needs would be 2 and 3 times greater (ranging from 0 to more than 1500 m3/ha) than current water needs at both climate change scenarios. Moreover, blooming date would advance from 3 to 6 weeks, harvest date from 1 to 2.5 months, resulting in growing cycles from 10 to 80 days shorter. It should also be noted that frost risk would decrease from 6 to 76%, the number of days with temperatures above 30ºC during ripening would rise from 48 to 500% and tropical nights (minimum temperature >20ºC) at ripening would increase from 28 to 150%, depending on the scenario and the DOs. The impacts of climate change in the three DOs could result in significant limitations for grapevine cultivation and wine production if adaptive strategies are not applied. This result could serve as a basis for the design of specific and particular adaptation strategies to improve and maintain vineyards in the DOs studied and could be extrapolated to similar DOs and regions.