Mining microbiome data to identify antagonists of grapevine downy mildew (Plasmopara viticola)

ine nitrogen deficiency can negatively influence the aroma profile and ageing potential of white wines. Canopy management can alter vine microclimate, affect the nitrogen availability and influence the response of leaf senescence. Increasing the nitrogen availability to vines can increase the Yeast Assimilable Nitrogen (YAN) levels in harvested fruit and wine. Studies show that foliar nitrogen and sulphur applications at véraison, on low YAN Sauvignon blanc grapes have an effect on the level of amino acids (Jreij et al. 2009) and on S-containing compounds such as glutathione and thiols (Lacroux et al. 2008), which in turn can influence the formation of major volatiles and the aroma profile of the wine.

Study the influence of sample preparation methods on the volatile organic compounds (VOCs) profiling for fermentative beverages by GCxGC-TOFMS analysis. METHODS: Five common sample preparation methods were tested on pooled red wine, white wine, cider, and beer. Studied methods were DHS, Liquid-liquid extraction, mSBSE, SPE and SPME. VOCs were analyzed by GCxGC-TOFMS followed by data analysis with ChromaTOF. RESULTS: The volatile organic compounds (VOCs) profiling results were very dependent on the sample preparation methods.

Tempranillo Tinto (TT) is the third-most planted red wine variety in the world, and it is mostly grown in the Iberian Peninsula. Spontaneous somatic variation appearing during vegetative propagation can be exploited to improve elite varieties as Tempranillo Tinto, including the selection of new phenotypes enhancing berry quality. We described previously that a somatic variant of TT with darker fruit color, the clone VN21, exhibits increased extractability of polyphenols during the winemaking process. To unravel the molecular mechanism underlying this phenomenon, we performed whole-genome resequencing to compare VN21 to other TT clones, revealing a 10 Mb deletion in chromosome 11 that likely affected only the L1 meristem cell layer of VN21 and tissues derived from it, such as external cell layers of berry skin.

Spring freeze events threaten grape production globally. As grape buds emerge from dormancy in spring, freezing temperatures have the potential to damage green tissues, decreasing yield potential and compromising fruit quality by harvest.

The development of interspecific hybrid varieties (ihvs) resistant to diseases such as powdery mildew and downy mildew allows for a decrease in the use of inputs in vineyards. In this pers-pective, ihvs represent a response to societal demand for reducing environmental impact and are increasingly used in viticulture. At the same time, wines resulting from so-called sponta-neous fermentations, based on indigenous flora, have recently gained popularity.