GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 Can soil water content be used as a predictor of predawn leaf water potential for deficit irrigation scheduling? A case study at Alentejo wine region

Can soil water content be used as a predictor of predawn leaf water potential for deficit irrigation scheduling? A case study at Alentejo wine region

Abstract

Context and purpose of the study: Water and heat stress impose new challenges to irrigation management in the Mediterranean areas. This reality has a major impact on the vineyard ecosystem, particularly on the scarce water resources of the Alentejo region (South Portugal). To mitigate this problem, irrigation management should focus on optimizing yield and fruit quality per volume of water applied. This work aims to discuss the use of predawn leaf water potential and soil water status relationships as a decision tool for irrigation management taking as basis data from a field trial where two deficit irrigation strategies were compared.

Material and methods: A deficit irrigation experiment was conducted from 2013-2015 at a commercial vineyard locatedat Reguengos de Monsaraz, Alentejo, Portugal (38o22’ N 7o33’ W) with the V. vinifera variety Aragonez (syn. Tempranillo). A sustained deficit irrigation (DI) strategy used by the farm consisting of a constant proportion of crop evapotranspiration (0.28) was applied along the irrigation period (DI1) and was compared with DI2, a similar strategy but with 48% lower water volumes than DI1, using a randomized complete block design with four replications of 15 plants. Predawn leaf water potential (ψPD) was used to define the beginning of each irrigation event.Soil water content until one meter depth was assessed and the fraction of transpirable soil water (FTSW) was calculated. Yield, berry composition and pruning weight were assessed. This paper reports the first year (2013) results.

Results: The DI strategies induced a decrease of ψPD along the season. In parallel, the progressive water withhold decreased FTSW (accessed after each irrigation event) along the season from 80 to 20%, while atmospheric water demand was increasing. The strong correlation between ψPD and FTSW observed may support the use of FTSW as a robust predictor of ψPD. The stressful conditions imposed by this irrigation strategy had no significant effect on yield, berry composition and vigor. The crop WUE (amount of fruit produced per unit of water applied) was higher for DI2 strategy and, at the same time, allowing water savings as compared to grower’s irrigation strategy.

DOI:

Publication date: September 28, 2023

Issue: GiESCO 2019

Type: Poster

Authors

Ricardo EGIPTO1,2*, Joaquim Miguel COSTA2, José SILVESTRE1, Manuela CHAVES3, Carlos M. LOPES2

INIAV, I.P., Pólo de Dois Portos, Quinta da Almoínha, 2565-191 Dois Portos, Portugal
LEAF, ISA, Universidade de Lisboa , Tapada da Ajuda Lisboa, Portugal
LEM-ITQB, Universidade Nova de Lisboa, Oeiras, Portugal

Contact the author

Keywords

deficit irrigation, water stress, crop WUE, yield and berry quality

Tags

GiESCO | GiESCO 2019 | IVES Conference Series

Citation

Related articles…

Rootstock regulation of scion phenotypes: the relationship between rootstock parentage and petiole mineral concentration

Grapevine is grown as a graft since the end of the 19th century. Rootstocks not only provide tolerance to Phylloxera but also ensure the supply of water and mineral nutrients to the scion. Rootstocks are an important mean of adaptation to environmental conditions, because the scion controls the typical features of the grapes and wine. However, among the large diversity of rootstocks worldwide, few of them are commercially used in the vineyard. The aim of this study was to investigate the extent to which rootstocks modify the mineral composition of the petioles of the scion. Vitis vinifera cvs. Cabernet-Sauvignon, Pinot noir, Syrah and Ugni blanc were grafted onto 55 different rootstock genotypes and planted in a vineyard as three replicates of 5 vines. Petioles were collected in the cluster zone with 6 replicates per combination. Petiolar concentrations of 13 mineral elements (N, P, K, S, Mg, Ca, Na, B, Zn, Mn, Fe, Cu, Al) at veraison were determined. Scion, rootstock and the interaction explained the same proportion of the phenotypic variance for most mineral elements. Rootstock genotype showed a significant influence on the petiole mineral element composition. Rootstock effect explained from 7 % for Cu to 25 % for S of the variance. The difference of rootstock conferred mineral status is discussed in relation to vigor and fertility. Rootstocks were also genotyped with 23 microsatellite markers. Data were analysed according to genetic groups in order to determine whether the petiole mineral composition could be related to the genetic parentage of the rootstock. Thanks to a highly powerful design, it is the first time that such a large panel of rootstocks grafted with 4 scions has been studied. These results give the opportunity to better characterize the rootstocks and to enlarge the diversity used in the vineyard.

EVIDENCE OF THE INTERACTION OF ULTRASOUND AND ASPERGILLOPEPSINS I ON UNSTABLE GRAPE PROTEINS

Most of the effects of ultrasound (US) result from the collapse of bubbles due to cavitation. The shockwave produced is associated with shear forces, along with high localised temperatures and pressures. However, the high-speed stream, radical species formation, and heat generated during sonication may also affect the stability of some enzymes and proteins, depending on their chemical structure. Recently, Ce-lotti et al. (2021) reported the effects of US on protein stability in wines. To investigate this further, the effect of temperature (40°C and 70°C; 60s), sonication (20 kHz and 100 % amplitude, for 20s and 60s, leading to the same temperatures as above, respectively), in combination with Aspergillopepsins I (AP-I) supplementation (100 μg/L), was studied on unstable protein concentration (TLPs and chitinases) using HPLC with an UV–Vis detector in a TLPs-supplemented model system and in an unstable white wine.

Impact of malolactic fermentation on volatile composition and sensory properties of white and rosé wine from the greek variety moschofilero

Moschofilero is a native grape variety, classified as a ‘gris’ type variety, that is cultivated in PDO Mantineia, Peloponissos, Greece. It is used for the production of both white and rosé wines. Due to high altitude of the vineyards, the harvest is done by mid October, and many vintages are characterised by high acidities and low pH values.

Whole bunch fermentation: adding complexity, or just making ‘green’ wine?

Certain grape varieties contain negligible levels of isobutyl methoxypyrazine (IBMP) in grapes. However, it has long been known that grape stems

Characterization of Mesoclimatic zones competent for the culture of vine (vitis vinifera l.) in the province of San Juan, Argentina

Le zonage agroclimatique a pour objet de caractériser des lieux ayant des aptitudes distinctes pour la production de la vigne. La province de San Juan en Argentine est l’une des régions vitivinicoles les plus chaudes du pays.