Terroir 2020 banner
IVES 9 IVES Conference Series 9 The vascular connections in grafted plants under examination

The vascular connections in grafted plants under examination

Abstract

Aims: Decreasing longevity of vineyards due to the increase in the infection of different grapevine trunk diseases is a growing concern, and could be related to the quality of grafting. The main aim of this study was to evaluate the use of xylem hydraulic conductivity measurements as a potential indicator for the quality of vascular connections in the graft junction of grapevine plants. For that purpose, two specific trials were carried out: (1) the quality of different batches of plants whose subjective quality was previously known from the nursery’s experience was evaluated, and (2) the vascular connections between the rootstock and the scion were evaluated on a different set of plants grafted using different grafting techniques.

Methods and Results: (1) The XYL´EM conductivity meter was used to measure the specific hydraulic conductivity (Ks) of plants from six different batches whose quality was subjectively defined from the nurseryman experience. Hydraulic conductivity was measured in one-year-old dormant plants, which were kept in a cold chamber since leaving the nursery, first on the whole plant, then on the rootstock and finally at the graft junction. Results showed that two of the six batches evaluated had significantly lower values than the others. (2) After reflecting on the previous experience, we decided to perform the measurements in growing plants, for which we used different batches of plants grafted using different techniques but keeping the same scion (Airén) and the same rootstock (110 R) in all of them. The grafting techniques used were ‘omega’, ‘full cleft’, ‘manual whip and tongue’, ‘mechanical whip and tongue’, and ‘V’. This time, Ksmeasurements were only carried out on the whole plant by determining the water flow from the scion to the rootstock. Results revealed a tendency that the maWT, meWT and V grafts had higher Ks values than FC or OM grafts, which corresponds to higher growth rates according to results previously collected on a field trial performed on the same type of grafted plants.

Conclusions:

Hydraulic conductivity measurements may be a useful trait for the evaluation of vascular connections between the rootstock and the scion in grapevine.

Significance and Impact of the Study: To the best of our knowledge, there are no similar studies in grapevine combining hydraulics measurements with grafting techniques. Results suggest that the hydraulic functioning at the graft junction could be an interesting tool to measure the quality/quantity of vascular connections on grafted plants, and be used to characterize batches in experimentation or, even, to evaluate batches from the nurseries as a quality control.

DOI:

Publication date: March 25, 2021

Issue: Terroir 2020

Type : Video

Authors

Diana Marín1*, José M. Torres-Ruiz2, F. Javier Abad1, 3, Luis G. Santesteban1

Dept. of Agronomy, Biotechnology and Food Science, Univ. Pública de Navarra, Campus Arrosadia, 31006 Pamplona, Spain
Université Clermont-Auvergne, INRAE, PIAF, 63000 Clermont-Ferrand, France
3 INTIA, Edificio de Peritos Avda. Serapio Huici nº 22, 31610, Villava, Spain

Contact the author

Keywords

Grapevine, Vitis vinifera L., omega graft, whip and tongue, alternative graft

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Relationships between the Fregoni bioclimatic index (IF) and wine quality

The Fregoni bioclimatic index (IF) considers the daily temperature range during the ripening month and the number of days with temperature below 10°C.

Mechanisms involved in the heating of the environment by the aerodynamic action of a wind machine to protect a vineyard against spring frost

One of the main consequences of global warming is the rise of the mean temperature. Thus, the heat summation by the plants begins sooner in the early spring, and by cumulating growing degree-days, phenological development tends to happen earlier. However, spring frost is still a recurrent phenomenon causing serious damages to buds and therefore, threatening the harvests of the winegrowers. The wind machine is a solution to protect fruit crops against spring frost that is increasingly used. It is composed of a 10-m mast with a blowing fan at its peak. By tapping into the strength of the nocturnal thermal inversion, it sweeps the crop by propelling warm air above to the ground. Thus, stratification is momentarily suppressed. Furthermore, the continuous action of the machine, alone or in synergy, or the addition of a heater allow the bud to be bathed in a warmer environment. Also, the punctual action of the tower’s warm gust reaches the bud directly at each rotation period. All these actions allow the bud to continuously warm up, but with different intensities and over a different period. Although there is evidence of the effectiveness of the wind machines, the thermal transfers involved in those mechanisms raise questions about their true nature. Field measurements based on ultrasonic anemometers and fast responding thermocouples complemented by laboratory measurements on a reduced scale model allow to characterize both the airflow produced by the wind machine and the local temperature in its vicinity. Those experiments were realized in the vineyard of Quincy, in the framework of the SICTAG project. In the future paper, we will detail the aeraulic characterization of the wind machine and the thermal effects resulting from it and we will focus on how the wind machine warms up the local atmosphere and enables to reduce the freezing risk.

Using image analysis for assessing downy mildew severity in grapevine

Aim: Downy mildew is a crucial disease in viticulture. In-field evaluation of downy mildew has been classically based on visual inspection of leaves and fruit. Nevertheless, non-invasive sensing technologies could be used for disease detection in grapevine. The aim of this study was to assess downy mildew severity in grapevine leaves using machine vision.

Sensory profiles of Shiraz wine from six Barossa sub-regions: a comparison between industry scale and standardised small lot research wine making

Aims: The Barossa wine region in South Australia comprises six sub-regions and is renowned for its Shiraz wines. However, there is no comprehensive documentation of the distinctive sensory characteristics of wines from these sub-regions.

Direct-injection HPLC for simultaneous determination of individual and total polyphenols in red wines: validation of the method

Polyphenols are very important compounds of red wines, serving as essential bioactive components and playing an important role in sensory properties. The determination of individual phenolic compounds in red wine is commonly performed by HPLC analysis, while the total polyphenols are quantified by spectrophotometric methods, usually by the method of absorbance at 280 nm (index of ribéreau-gayon) or the method of index of folin-ciocalteu. In this work, we pioneeringly proposed a new and fast method for simultaneous determination of individual and total polyphenols in red wines by direct-injection HPLC without sample preparation.