Organic mulches improve vine vigour, yield and physiological response in a semi-arid region

In a context of sustainable agriculture, “agroecological immunity” is an emerging concept to reduce the use of chemical pesticides to protect crops against pathogens. This alternative strategy aims to combine different levers including the use of “bio”solutions. These include biocontrol products, some of which being plant defense elicitors, as well as products authorized in organic farming such as copper or sulfur. In vineyards, depending on climate conditions, powdery and downy mildews can be devastating diseases.

When considering the application of a systemic approach to assess the intrinsic complexity of agricultural production, the following question immediately arises

Consumers typically prefer wines with floral and fruity aromas over those presenting green-pepper, vegetal or herbaceous notes. Pyrazines have been identified as causatives for herbaceous notes in wines, especially Bordeaux reds. However, pyrazines are not universally responsible for herbaceousness, and several other wine volatile compounds are known to produce distinct vegetal/herbaceous aromas in wines. Specifically, volatile aldehydes elicit sensations of herbaceousness or grassiness and have been described in wines well above their perception thresholds.

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.

The vineyard world is faced to a lot of fungal diseases. Grapevine Trunk Diseases (GTD) are some of the major. After exhibiting chronical foliar symptoms, grapevines can die by apoplexy within only few days. A range species of fungi was described to be associated with the apparition of early symptoms of GTD. It is well known that ozone dissolved into water is a powerful disinfectant with no remanence. The main goal of this study was to test the efficiency of this process on different fungal species associated with GTD in vitro and in planta conditions.