Development and application of CRISPR/Cas in grapevine

Knowledge of the nitrogen nutrition status of grapevines is essential for the sustainable management of their nutrition for the production of quality grapes. The measurement of the chlorophyll index is a rapid, non-destructive and relatively inexpensive method that provides a good approximation of the nitrogen nutrition status of the vine during the season. Interpretation thresholds are currently insufficient or non-existent for some chlorophyll meters. Ideally, they should be available for each variety and each phenological stage. In order to popularize the use of chlorophyll-meters, measurements were carried out at Agroscope in Switzerland to establish the correlation between the indices obtained by the devices N-tester and SPAD 502.

Stomata are microscopic pores mainly located in leaf epidermis, allowing gas exchanges between plants and atmosphere. Stomatal initiation relies on the transcription factor SPEECHLESS which is mainly regulated by the MAP kinase cascade, in turn controlled by small signaling peptides, the Epidermal Patterning Factors (EPF and EPF-Like), namely EPF1, EPF2 and EPFL9. While EPF1 and EPF2 induce the inhibition of SPEECHLESS, their antagonist, EPFL9, stabilizes it, leading to stomatal formation. In grapevine, there are two paralogs for EPFL9, VviEPFL9-1 and VviEPFL9-2. Despite their structural similarity, it remains unclear whether they are differentially regulated and have distinct roles.

A part, at least, of red wines fruity expression may be explained by perceptive interactions involving particularly various substituted ethyl esters and acetates present at concentration far below their olfactory threshold, specifically thanks to synergistic effects. Wine sensory perception is directly linked to the stimulation of the taster at the level of olfactory epithelium by volatiles. These compounds are liberated from the matrix to the atmosphere, and will then be smelt. From a physico-chemical point of view, these volatiles ability to be released may be evaluated by their partition coefficients, which correspond to the volatile concentration ratio between the liquid and gas phase. Our goal is, through these coefficients determination, to assess if volatile matrix composition is able to impact the volatility of some compounds, and then explain sensory perception, i.eto evaluate what is called the pre-sensorial level impact.

Several Eurasian wild grapevine populations were found along Extremadura region (southwestern Spain). For conservation and study, one individual from four different populations (named L1, L2, L5 and L6) was vegetatively propagated and planted at Instituto de Investigaciones Agrarias Finca La Orden (CICYTEX), Badajoz. The aim of the present work was to characterize those conserved individuals from four different populations based on both an ampelographic description and a molecular analysis. Three vines per individual were studied.

L’étude porte sur trois terroirs du Roussillon, classés dans l’A.O.C. Muscat de Rivesaltes et concerne les 2 cépages de cette appellation : le muscat à petits grains et le muscat d’Alexandrie. Elle a pour objectif de connaître pour un terroir donné le meilleur choix de cépage.