Effect of soil particle size on vine water status, leaf ABA content and berry quality in Nebbiolo grapes

Volatile organic compounds (VOCs) are emitted by nearly all plant organs of the plants, including leaves. They play a key role in the communication with other organisms, therefore they are involved in plant defence against phytopathogens. In this study VOCs from grapevine leaves of two varieties of Vitis vinifera infected by Erysiphe necator were analysed. The varieties were selected based on their susceptibility to pathogen, Kishmish Vatkana has the Ren1 resistance gene and Zamarrica showed high susceptibility in previous trials.

Condensed grape tannins play a major role in the organoleptic properties and quality of red wine. Recently, a new sub-family of macrocyclic condensed tannins has been identified in red wine and named “crown tannins”. Indeed, the first compound of the family identified and characterised by NMR was the crown procyanidin tetramer which is composed of a macrocyclic structure composed of four (-)-epicatechins link together by B-type interflavanoid linkage in the following an alternative sequences of C4-C8 and C4-C6 linkage. The 3D structure of this unusual crown procyanidin family reveals a central cavity in the molecule [1].

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.

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).

Botanist Andreas Raphael Wolny collected a grapevine herbarium from 1812-1824 in Sremski Karlovci (wine region of Vojvodina, Serbia), which represents local cultivated grapevine diversity before the introduction of grape phylloxera in the region. The herbarium comprises over 100 samples organized into two subcollections based on berry colour (red and white varieties), totaling 47 different grape varieties. The objective of this study was to investigate the historical varietal assortment of Balkan and Pannonian winegrowing areas with long viticulture traditions.