Mining microbiome data to identify antagonists of grapevine downy mildew (Plasmopara viticola)

Ectopic RNA application for plant defense faces challenges in tree crops, including size, diffusion, and stability of active compounds such as ribonucleoproteins and nucleic acids. While existing strategies involve expressing dsRNA in transgenic plants targeting pathogens, our research strives to develop a transient RNAi system based on Spray-Induced Gene Silencing (SIGS). This approach aims to circumvent legal barriers and public concerns associated with genetically modified organisms (GMOs). Our strategy integrates SIGS with branched polyethyleneimine-functionalized Carbon Dots (bPEI-CDs) as nanocarriers, effectively addressing unique delivery challenges in plant defense as RNA stability and uptake enhancement

Gum arabic is composed of a polysaccharide rich in galactose and arabinose along with a small protein fraction [1, 2], which gives its stabilizing power with respect to the coloring substances or tartaric precipitation of bottled wine. It is a gummy exudation from Acacia trees; the products used in enology have two possible botanical origins, i.e. Acacia seyal and Acacia senegal, with different chemical-physical features and consequently different technological effects on wines. The aim of this work is to evaluate the feasibility of discrimination of commercial gums Arabic between their two different sources, on the basis of the absorption of the Fourier Transform Infrared (FT-IR) spectra of their aqueous solutions, in order to propose an extremely rapid and cost-saving method for quality control laboratories.

Variegation, a frequently observed trait in plants, is characterized by the occurrence of white or discoloured plant tissue. This phenomenon is attributed to genetic mosaicism or chimerism, potentially impacting the epidermal (L1) and subepidermal (L2) cell layers. In grapevine, variegation manifests as white or paler leaf, flower, or berry tissues, often leading to stunted growth and impeded development. Despite its prevalence, variegation in grapevines remains understudied.

A worrying drop in the acidity of wines has been observed in many wine regions, such as Bordeaux (Merlot), Burgundy (Pinot Noir), Côtes-du-Rhône (Grenache) or Rioja (Tempranillo). This lack of acidity is particularly marked in the Midi-Pyrenean vineyards of the Côtes du Frontonnais (Tournier, 1993). However, the acidity of a wine is one of the main factors of its quality, in fact, a low acidity combined with an insufficient tannic structure leads to rapid oxidation of wines and makes them age prematurely.

It is well-known that there is a relationship between the “terroir” and the characteristics of grapes and quality of wines. However, adequate grape variety and other cultural factors should be also taken into account