Essai de maîtrise optimisée de la vigueur de deux clones de chenin sur schistes verts du carbonifère en zone A.O.C. Coteaux du Layon

In this audio recording of the IVES science meeting 2022, Antonio Morata (Universidad Politécnica de Madrid, Madrid, Spain) speaks about the use of fumaric acid to control pH and inhibit malolactic fermentation in wines.

The terroir concept is presented as the basis of the A.O.C system, in the french vineyards. The “Anjou terroirs” programme aims at bringing the necessary scientific basisfor a rational and reasoned exploitation of the terroir. lt must lead to finalizing a lighter, more relevant integrated method of characterisation wich could be generally applied.

Mannoproteins (MPs) are proteoglycans from the outmost layer of yeast cell walls released into wine during alcoholic fermentation and ageing on lees processes. The use of commercial preparations of mannoproteins as additives to improve wine stability with regards to the crystallization of tartaric salts and to prevent protein haze in the case of white and rosé wines is authorized by the OIV.
Regarding red wines and polyphenols, mannoproteins are described as able to improve their colloidal stability and modulate the astringent effect of condensed tannins. The latter interact with salivary proteins forming insoluble aggregates that cause a loss of lubrication in the mouth and promote a drying and puckering sensation. However, neither the interaction mechanisms involved in mannoproteins capacity to impact astringency nor the structure-function relationships related to this property are fully understood.

– Several practices can be applied to vineyards in order to ensure good healthy for grapevines, adequate yield and fruit quality. Among them, the use of cover crops is a relevant option for soil management. It increases the organic matter, improves water infiltration, reduces risks of soil erosion and greenhouse gas emissions, in addition improving biodiversity in the vineyard.

Somatic embryogenesis (SE) has been used in a variety of biotechnology applications such as virus elimination, cryopreservation, induced mutagenesis and genetic transformation. The SE induction process may cause DNA alterations and ploidy changes, which may provide a source of genetic variability useful for the improvement of agronomic characteristics of plants. This research aims at investigating the spontaneous alterations of the genome in grapevine plants regenerated through SE. Regenerants obtained from different embryogenic events from three different grapevine genotypes (Catarratto, Frappato and Nero d’Avola) were analysed.