Effect of abiotic stress and grape variety on amino acid and polyamine composition of red grape berries

Climate change has numerous detrimental consequences and creates new challenges for viticulture around the world. Transitory or constant high temperatures frequently associated with an excess of sunlight (UV) can cause a variety of physiological disorders, such as sunburn. Diverse environmental factors and the plant’s response mechanisms to stress determine the symptoms. Grapevine berry sunburn leads to a drastic reduction in yield, and may eventually decline berry quality. Consequently, this poses a significant risk to the winegrowers.

Viticulture is globally important for socioeconomic and environmental reasons. The EU is globally leading grape and wine production, and Spain is among the top grape and wine producers. As climate change affects viticulture, mitigation and adaptation are crucial for protecting grape production. In this research work, data on viticultural management practices such as soil cultivation, irrigation, energy, machinery, plant protection and the use of fertilizers from vineyards located in Logroño (La Rioja) have been obtained.

Less and less chemical plant protection products are approved by the E U. Plant pathogenic fungi become increasingly resistant to the active ingredients that have been around for a long time. Besides, there is a valid demand for effective products that can be applied in organic cultivation.
We examined Metschnikowia strains under laboratory conditions in order to find effective strains against B. cinerea. The antimicrobial mechanism of these yeasts is based on the competition for the ferric ions from the environment. Metschnikowia cells release the pulcherriminic acid which chelates with Fe3+, forming the pigment pulcherrimin.

Brandy de Jerez (BJ) is a spirit drink made exclusively from spirits and wine distillates and is characterized by the use of casks for aging that previously contained Sherries. The quality and sensory complexity of BJ depend on the raw materials and some factors: grape variety, conditions during processing the wine and its distillation, as well as the aging in the cask. Therefore, the original compounds of the grapes from which it comes are of great interest being in most cases the Airén variety. Their relationship with the quality of the musts and the wines obtained from them has been studied (1) and varies each year of harvest depending on the weather conditions (2).

Ozone is a potent oxidizing compound that quickly decomposes into oxygen without residues. Previous works reported that ozone is not only a disinfectant that directly harms the pathogens of the vine but also activates systemic defense systems in the plant by activating oxidative stress. We assume these systemic defense mechanisms are essential to the vines’ resistance to downy and powdery mildew (Plasmopara viticola & Erysiphe necator, respectively). The goals of the research are to examine the effect of spraying with ozone water on the plant’s resistance against the mentioned pathogens as well as to characterize the metabolic profile of the plants treated with ozone as well as physiological characteristics in the vines such as the level of Photosynthesis and crop yield. Vines in the vineyard sprayed with ozone water at concentrations of 2 and 4 PPM weekly and biweekly, untreated control & conventional spray. Leaves were taken from vines 2,4,7,9 and 11 days after exposure to ozone and inoculated with the pathogens.