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IVES 9 IVES Conference Series 9 Rootstock regulation of scion phenotypes: the relationship between rootstock parentage and petiole mineral concentration

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

Abstract

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.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Marine Morel, Sarah Cookson, Nathalie Ollat, and Elisa Marguerit

EGFV, Univ. Bordeaux, Bordeaux Sciences Agro, INRAE, ISVV, Villenave d’Ornon, France

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Acknowledgements: We would like to acknowledge the assistance of all the interns who helped to sample the petioles particularly Gwénaëlle Boué, Elia Breuillot, Louis Rhulé, Pacôme Chatterjee, and the technical staff involved on the setting of the GreffAdapt experimental vineyard, particularly the unite Expérimentale Viticole de Bordeaux 1442, INRAE 

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IVES Conference Series | Terclim 2022

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