PIWIs’ variation in drought response under semi-controlled conditions 

Aim: Among Botryosphaeriaceae species associated with Botryosphaeria dieback of grapevines, Neofusicoccum parvum is one of the most virulent and fastest wood-colonizing fungi. This study aimed to evaluate the susceptibility of six red grapevine cultivars (“Bobal”, “Monastrell”, “Garnacha Tinta”, “Moravia Agria”, “Tinto Velasco” and “Moribel” to N. parvum, under field conditions.

Tartrate precipitation affects the properties of wines, due to the formation of crystals that cause turbidity, even after being bottled. The forced tartaric stabilization is carried out frequently for young wines, through various physicochemical procedures. The traditional treatment for tartaric stabilization is refrigeration, but it can have a negative effect on wine’s sensory properties, and particularly on the color of red wines. The aim of this study was to evaluate the effect of different tartaric stabilization options on the color and phenolic composition of Tannat red wines from Uruguay.

Undesirable compounds in wine, like OTA, biogenic amines, and pesticide residues, can negatively affect its quality and pose health risks to consumers. In addition, an excess of tannins can lead to an unpleasant rise in astringency and bitterness, which makes tannins another target of reduction.

Developing rootstocks adapted to environmental constraints constitutes a key lever for grapevine adaptation to climate change. In this context, Near Infrared Spectroscopy (NIRS) could be used as a high-throughput phenotyping technique to simplify the study of rootstocks in grafted situations. This study is an exploratory analysis to evaluate the potential of NIRS acquired on grafted tissues to reveal rootstock effects as well as the plasticity of combinations of scion/rootstock to better characterize these interactions.
Through the study of 25 combinations (5 scions times 5 rootstocks) in a dedicated experimental vineyard, we showed that NIRS obtained from grafted tissues capture rootstock and scion/rootstock interaction signals, up to 20% of the total variance at specific wavelengths.

Rootstocks are gaining importance in viticulture as a strategy to combat abiotic challenges, as well as enhancing scion physiology and attributes. Therefore, understanding how the rootstock affects photosynthesis is insightful for genetic improvement of either genotype in the grafted grapevines. Photosynthetic parameters such as maximum rate of carboxylation of RuBP (Vcmax) and the maximum rate of electron transport driving RuBP regeneration (Jmax) have been identified as ideal targets for breeding and genetic studies. However, techniques used to directly measure these photosynthetic parameters are limited to the single leaf level and are time-consuming measurements.