Application of satellite-derived vegetation indices for frost damage detection in grapevines

Le travail concerne en premier la méthodologie de caractérisation du climat des vignobles, à l’échelle du macroclimat des régions viticoles du monde (géoviticulture). Trois indices climatiques viticoles synthétiques

Today’s viticulture faces a considerable challenge dealing with fungal diseases and limitations on the use of plant protection products (PPP) have increased the pressure to find more sustainable alternatives. One strategy may be the development and cultivation of disease-resistant grapevine varieties (PIWI) that could maintain crop productivity and quality while reducing dependence on PPP. In this work a set of 9 PIWI varieties (5 white and 4 red) deploying genes for resistance to powdery and downy mildew were evaluated in two consecutive years in Valdegón, La Rioja, with Tempranillo and Viura as controls. The objective was to correlate agronomic performance and disease incidence with the presence of disease resistance genes in two different seasons: with (2023) and without disease pressure (2022).

Addressing the opportunities and challenges of genomics methods in grapevine (Vitis vinifera L.) requires the development of a comprehensive and accurate reference genome and annotation. We aimed to create a new gene annotation for the PN40024 grapevine reference genome by integrating the highly accurate and complete T2T assembly and the manually curated PN40024.v4 annotation. Here, we present a novel workflow to enhance the annotation of the T2T genome by incorporating past community input found in PN40024.v4. The pipeline’s containerization will improve the workflow’s reproducibility and flexibility, facilitating its inclusion as a shared workflow on the Grapedia portal, the grapevine genomics encyclopedia.

The reflectance spectra of vegetation carry potentially useful information that can be used to determine chemical composition and discriminate between vegetation classes. If compared with analytical methods such as conventional chemical analysis, reflectance measurement provides non-destructive, economic, near real-time data. 

In a previous work1, it was suggested that the different contents in delphinidin and catechin of the grapes were determinant on the O2 consumption and Strecker aldehyde (SAs) accumulation rates. Higher delphinidin seemed to be related to a faster O2 consumption and a smaller SAs accumulation rate, and the opposite was observed regarding catechin.
In the present paper, these observations were fully corroborated by adding synthetic delphinidin to a wine model containing polyphenolic fractions (PFs) extracted from garnacha and synthetic catechin to a wine model containing PF extracted from tempranillo: The delphinin-containing garnacha model consumed O₂ significantly faster and accumulated significantly smaller amounts of SAs than the original garnacha model, and the catechin-containing tempranillo model, consumed O2 significantly slower and accumulated significantly higher amounts of SAs than the original tempranillo model.