In viticulture, the control of the crop load is largely used as an important instrument for the regulation of yield and grape quality, which in turn leads to quality wines. One of the practices for the regulation of crop load, often used for table grapes, is the green harvest, that is, the removal of some unripe bunches in order to drive more of the vines' strength towards the remaining clusters. At present this practice is also applied for wine grapes, regulating in this way the yield and the quality of grapes and wines, due to a better accumulation of sugar in the berries of the remaining bunches and a better accumulation of aromatic and colour compounds into the grape skins. In this paper we present the results regarding the usability and agro-biological behaviour to green harvesting of two vine cultivars (Feteasca Neagra and Cabernet Sauvignon) grown in organic plantations in Murfatlar vine region, as compared to controls without cluster thinning. The main parameters followed were the indicators of grape quality (sugar concentration, total acidity, pH, anthocyanins and total polyphenolic index) and the technological parameters (the average weight of the cluster, the weight and number of the berries, the rachis weight and the yield per vine). The statistical analysis of the results showed that the green harvest had a beneficial effect on the grape composition and wine quality for both varieties.

(1) Background. An extensive survey of grapevine-sown cover crops and spontaneous weed flora was conducted from 2019 to 2020 in organic vineyards in six European countries (France, Italy, Romania, Slovenia, Spain, Switzerland). Our main objective was to detect and identify the presence of Cylindrocarpon-like asexual morphs species associated with black-foot disease on their roots. (2) Methods. Fungal isolations from root fragments were performed on culture media. Cylindrocarpon-like asexual morph species were identified by analyzing the DNA sequence data of the histone H3 (his3) gene region. In all, 685 plants belonging to different botanical families and genera were analyzed. Cylindrocarpon-like asexual morphs were recovered from 68 plants (9.9% of the total) and approximately 0.97% of the plated root fragments. (3) Results. Three fungal species (Dactylonectria alcacerensis, Dactylonectria torresensis, Ilyonectria robusta) were identified. Dactylonectria torresensis was the most frequent, and was isolated from many cover crop species in all six countries. A principal component analysis with the vineyard variables showed that seasonal temperatures and organic matter soil content correlated positively with Cylindrocarpon-like asexual morphs incidence. (4) Conclusions. The presence of Cylindrocarpon-like asexual morphs on roots of cover crops suggests that they can potentially act as alternative hosts for long-term survival or to increase inoculum levels in vineyard soils.

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