The invasive seaweed Rugulopteryx okamurae: an innovative plant protective extract

Faced with the likely withdrawal of commercial specialities from use in the short to medium term, France has decided to implement an ambitious action plan to anticipate and avoid withdrawal without alternative solutions. The French wine industry (cniv and ifv) has been heavily involved in this action to define priorities. faced with the risk of the withdrawal of multi-site fungicides (folpel, dithianon, copper) coupled with the probable reduction in single-site fungicide solutions, mildew and black rot have been identified as the priority uses.

The intricate relationship between the necrotrophic pathogen Botrytis cinerea and grape berries (Vitis vinifera spp.) can lead to the development of either the desirable noble rot (NR) or the unfavourable grey rot (GR), depending on the prevailing weather conditions.

The effect of two rootstocks of different drought tolerance (1103 Paulsen and 3309 Couderc) on sap flow, water relations and gas exchange of cv. Xinomavro (Vitis vinifera L.) was investigated during the 2005 season in Naoussa, Greece. Soil was maintained at field capacity for both rootstock treatments until mid July when a restricted water regime was applied by irrigation cutoff. Sap flow diurnals for the Xinomavro-1103P combination showed a rapid decrease of flow after midday, under water stress conditions.

Nitrogen (N) uptake by grapevine roots in forms like nitrate, ammonium, urea, or amino acids influences vegetative and generative growth, impacting grape quality and wine sensory profile. The study examined nitrogen’s influence on phenolic compounds in leaves, berries, and wine across different scales — hydroponics, soil culture, and vineyard trials. Nitrogen forms altered metabolite patterns in leaves and wine significantly, affecting aroma and flavor. Key nitrogen assimilation enzymes (NR, NiR, GS) in grapevine rootstocks responded to nitrogen forms and timing. Hydroponically grown rootstocks fertilized with various forms showed differences in enzyme expression and activity, suggesting rootstocks can assimilate amino acid glutamine (Gln).

Grape ripening is a critical phenophase during which many metabolites driving wine quality are accumulated in berries. Major changes in berry composition include a rapid increase in sugar and a decrease in malic acid content and concentration. Its duration is highly variable depending on grapevine variety, climatic parameters, soil type and management practices.