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IVES 9 IVES Conference Series 9 Settling precocity and growth kinetics of the primary leaf area: two indicative parameters of grapevine behaviour

Settling precocity and growth kinetics of the primary leaf area: two indicative parameters of grapevine behaviour

Abstract

[English version below]

Le comportement de la vigne en terme de fonctionnement thermique et hydrique, influe de manière directe sur la qualité des baies de raisin. L’effet du terroir peut être perçu à travers l’étude de paramètres tels que la précocité, la mise en place de la surface foliaire ou la vigueur. Une expérimentation a été conduite en Val de Loire sur le cépage chenin dans le but de mieux comprendre le rôle des variables liées au terroir sur la croissance et le développement de la vigne et in fine sur la qualité des baies. Le protocole, basé sur des mesures agro-viticoles et des analyses physico-chimiques réalisées entre 1997 et 2001 s’appuie sur un réseau de 5 parcelles expérimentales, établi en 1990. Ce réseau repose sur le modèle de milieu physique «roche-altération-altérite», élaboré par MORLAT (1998). Des résultats significatifs ont été mis en évidence quant à la précocité de mise en place du feuillage et la vitesse d’accroissement de la surface foliaire. La précocité d’apparition du feuillage diffère en fonction du milieu rencontré, roche, altération ou altérite, la précocité de mi-débourrement sur le milieu roche étant plus forte. La vitesse d’accroissement de la surface foliaire varie également en fonction du milieu. Les parcelles sur roche, plus précoces, ont leur vitesse d’accroissement du feuillage primaire la plus importante plusieurs semaines avant floraison. Sur milieu altérite, plus tardif, la vitesse d’installation du feuillage est significativement plus élevée quelques semaines avant la floraison, voire même durant la floraison; ce qui induit une plus forte concurrence entre le cycle végétatif et reproducteur de la vigne. Les terroirs les plus tardifs sont caractérisés par une teneur en sucres des baies plus faible. Il apparaît une corrélation négative entre une mise en place tardive du feuillage primaire, la vitesse d’accroissement de la surface foliaire et la qualité de la baie. En particulier, l’indice de maturité et le rapport acide tartrique/acide malique semblent bien discriminer les terroirs représentatifs de différents types de fonctionnement de la vigne.

The behavior of the grapevine, in terms of thermic and hydric functioning, has a direct effect on the composition of the berries at harvest time. The «terroir » effect on the vine can be approached through the study of some parameters such as the earliness of the phenological stages, the settling of the leaf area and the vigor. An experiment was conducted in the Mid- Loire valley, with the chenin variety, in order to understand better the role of the «terroir » variables on the growth and development of the vine, and in fine on the quality of the berries. The data were obtained over the period 1997-2001 out of a network of 5 experimental plots, characterized by the intensity of the weathering process of their bed-rock : from low (rock type soil) to high (weathered type soil), according to the model proposed by MORLAT (1998). All plots were managed the same way. Significative differences between terroirs were observed concerning the precocity of the establishment of the primary leaf area and its growth kinetics. The primary leaf area settled earlier on the rock type soils than on the weathered type soils. On the former, the growth kinetics reached its highest level several weeks before flowering, while on the latter; the quicker increase of the leaf area took place just a few weeks before or even during the flowering stage. On the weathered type terroirs, this late increase induces a stronger competition between the vegetative and the reproductive cycles for the photosynthetic metabolites; at that stage (fruit set), the grapevine needs still to spend much energy to build its leaf area. Regarding berry composition, terroirs corresponding to the weathered type soils were found to produce less sugars and more malic acid than the rock type terroirs. This experiment showed a negative correlation between a late settling of the leaf area, its rapid growth and the quality of the berries. Two particular indexes – the maturity index and the tartaric/malic acid ratio – seem able to discriminate the terroirs regarding their different functioning mode.

DOI:

Publication date: February 15, 2022

Issue: Terroir 2002

Type: Article

Authors

Laurence STEVEZ (1), Gérard BARBEAU (2), Yves CADOT (2), Marie-Hélène BOUVET (2), Michel COSNEAU (2), Christian ASSELIN (2)

(1) Ecole Supérieure d’ Agriculture, 55 rue Rabelais, 49007
(2) INRA-UVV, 42 rue Georges Morel, 49071 Beaucouzé Cedex

Contact the author

Keywords

vigne, surface foliaire primaire, précocité, vitesse de croissance, qualité
grapevine, ptimary leaf area, precocity, growth kinetics, quality

Tags

IVES Conference Series | Terroir 2002

Citation

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