Preliminary steps of a protocol to isolate transcription factors bound to a specific DNA locus in grapevine using CRISPR-dCas9 system

In viticulture, microbial communities – particularly fungi – play a vital role in plant health, disease management, and grape quality.

ulfur compounds in wine have been studied for several years due to their impact on wine flavour, but the role of polysulfides is a recent topic. Polysulfides in wine are formed when two sulfhydryl groups oxidize, especially in presence of elemental sulfur or metal catalysts from field treatment residues (Ugliano et al. 2011). These compounds are odourless, but can degrade during storage and affect the wine quality. The mechanism of their formation is still largely unknown but different chemical and biochemical pathways have been suggested. Disulfides from cysteine (Cys) and glutathione (GSH) have been revealed in model wines (Kreitman et al. 2016) and more recently also higher polymerized forms in real wines (Van Leeuwen et al. 2020). Volatile varietal thiols like 3-mercaptohexanol (3MH) and 4-mercaptopentanone (4MMP) – flavour compounds with tropical or fruity notes – could undergo similar reactions, also with Cys and GSH, subsequently losing their flavour property (fate). Even more concerning is the possible release of H2S from polysulfides during storage, leading to undesired off-flavours (Sarrazin et al. 2010).

Climate change, particularly drought stress, threatens viticulture sustainability. Understanding scion-rootstock interactions and their link to the grapevine microbiome is key to improving vine health, productivity, and drought resilience.

Sfursat di Valtellina is a DOCG reinforced wine produced in Valtellina from partially withered red grapes of Vitis vinifera L. cv. Nebbiolo. The grape ripeness degree and the dehydration process strongly influence the physicochemical characteristics of grapes [1, 2, 3]. In particular, grape skin and seeds contain several classes of phenolic compounds strictly associated with red wine quality, which are significantly affected by these factors [4]. The aim of this research is to assess the combined influence of different ripeness levels and withering rates on the standard chemical composition and phenolic profile of winegrape in order to provide new insights and approaches to the management of withering, searching for the valorization of grape potentialities.

Phenology scales widely adopted by viticulturists (i.e., BBCH or modified E-L systems) are classification tools that describe seasonal and precisely recognized stages of fruit growth and development based on specific descriptors such as visual/physical traits or easy-to-measure compositional parameters.