Cumulative effect of deficit irrigation and salinity on vine responses

Contamination problems arising from the use of pesticides in viticulture have raised concerns. One of the alternatives to reduce contamination is the use of elicitors, molecules capable of stimulating the natural defences of plants, promoting the production of phenolic compounds (PC) that offer protection against biotic and abiotic stress. Previous studies on Cabernet-Sauvignon seedlings demonstrated that foliar application of elicitors methyl jasmonate (MeJ) and benzothiadiazole (BTH) increased proteins and PC involved in grapevine defence mechanisms. However, no trials had been conducted on Monastrell seedlings, a major winegrape variety in Spain.

Microorganism-based inoculants have been suggested as a viable solution to mitigate the adverse effects of climate change on viticulture. However, the actual effectiveness of these inoculants when applied under field conditions remains a challenge, and their effects on the existing soil microbiota are still uncertain. This study investigates the impact of arbuscular mycorrhizal fungi inoculation on grapevine performance and microbiome. The study was conducted in a vineyard of Callet cultivar in Binissalem, Mallorca, Spain. Two different treatments were applied: control and inoculation with commercial mycorrhizae complex of Rhizoglomus irregulare applied to plants through irrigation.

Modern agriculture employs large amounts of plastics, such as mulching and greenhouse films, thermal covers, plant protection tubes and tying tape. The latter two types are very common in viticulture. Guard tubes are employed to protect young vines from mechanic and atmospheric damage, whilst polymeric tying tape has replaced natural-origin materials to hold the canopy of vines. Both materials are made on synthetic polymers, which include a range of additives to improve their environmental stability remaining in the environment of vineyards for years. During this time, they are exposed to the range of pesticides (fungicides, insecticides and in a lesser extend herbicides) applied to vines.

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.

The sustainability of viticulture in response to climate change has been addressed mainly considering agronomic impacts, such as water management and diseases, either separately or together.
In grapevines, there is strong evidence that different genotypes respond differently to biotic and abiotic stresses. A screening was conducted on various local cultivars in response to drought and Neofusicoum parvum infection aiming to evaluate their susceptibility to abiotic stress and resistance to fungal diseases.