Evaluation of the potential of near infrared spectroscopy (NIRS) to characterize rootstock effects on grapevines, with a view to applications in high-throughput phenotyping ; Évaluation du potentiel de la spectroscopie proche infrarouge (NIRS) pour caractériser les effets porte-greffes sur vigne, en vue d’applications en phénotypage à haut débit

Developing grapevine rootstocks that are adapted to environmental constraints is a major tool for viticulture resilience. NIRS (Near InfraRed Spectroscopy) could be used as a high-throughput phenotyping method, in order to ease rootstocks studies, directly on grafted grapevines. This study consists of an exploratory analysis which aims at: checking if NIRS spectra from scion tissues show rootstocks’ effects; studying if the method reveals the plasticity of scion/rootstock combinations and if we were able to better characterize the scion/rootstock interactions.The study of 25 combinations from five scions and five rootstocks in an experimental field has allowed us to determine that the NIRS spectra of scion’s tissues catches signal from rootstock and scion/rootstock interactions. Scion’s effect has been stronger compared to rootstock’s effect on NIRS spectra. It was also true concerning agronomic traits such as phenology or accumulated biomass. Ex-situ leaves NIRS spectra caught rootstock’s effect more efficiently than wood’s ones or in-situ measured spectra. From these ex-situ leaves matrices specific rootstock’s effect wavelengths have been identified.Predictions of 28 phenotypic traits, at a grafted grapevine scale, have shown a difference on the predictive ability between traits. Concerning ex-situ leaves, three spectral range which contributes almost exclusively to predict traits were identified. A look on the contributions but also on the stability of predictive ability between complete leave’s spectra and partial leave’s spectra made of wavelengths belonging to one of these three spectral range, suggest that NIRS spectra carry genetic information. This genetic information describes the genotypes combination of a grafted grapevine. The feasibility of scion/rootstock co-breeding is an interesting prospect of genetic information catching in the case of grafted grapevines. ; Proposer des porte-greffes de vigne adaptés aux contraintes environnementales est un des leviers majeurs d’adaptation de la viticulture ...