The methods applied for DNA extraction from must and wine samples with monovarietal origin are presented and discussed aiming to prove the quality of extracted DNA and its good properties for further use in molecular tests. In the present research were compared four different DNA extraction methods from must and wine samples obtained from eleven V. vinifera varieties (five grapevine varieties for white wines and six grapevine varieties for red wines, respectively). Taking into consideration the amounts of obtained DNA, the concentrations and purities of the final DNA extracts, were stood out two modified methods. For all must samples, very efficient was the second method, which allowed obtaining a mean value of 87.9 ng µl-1 for the DNA concentration with 1.55 purity. Among the tested procedures, for monovarietal wine samples, the fourth method proved to be the most efficient which brought a mean value of 64.7 ng μl-1 for DNA concentration with 1.66 purity. This method adequate for wine samples involves two CTAB solution treatments and the RNase treatment applied before DNA resuspension. The DNA from must and wine extracts and the DNA from leaves of the corresponding grapevine varieties were amplified with five specific microsatellite primers (VVS2, VVMD27, VVMD32, VrZAG79 and VrZAG62). The aspects of pattern profiles were analysed in parallel and proved that the extracted DNA was suitable for amplification with these specific V. vinifera primers. The two selected extraction procedures are considered good for research purposes and ensure obtaining of good-quality extracted DNA from musts and one-year old wines.

The influence of climatic factors on grape yield, fertility indicators of grapes (absolute coefficient of fertility, relative coefficient of fertility, absolute productivity indices, relative productivity indices), but also sugar and total acidity content in three cultivars of 'Fetească' ('Fetească Albă', 'Fetească Neagră' and 'Fetească Regală', respectively) was evaluated during 2016-2020 2016 period at the experimental field of National Research and Development Institute for Biotechnology in Horticulture Ștefănești. The highest grape yield were recorded in 2018 to all three Cultivars analysed (20,33 t/ha 'Fetească Albă', 19,44 t/ha 'Fetească Neagră' and 19t/ha 'Fetească Regală', respectively), while the lowest values were measured in 2016 at all cultivars. Highest sugar content was measured in 2019 and 2020, and lowest in 2017, 2016, respectively. The highest acid content was recorded in 2017 and 2016 (4,64 g/l, 4,65 g/l, respectively) as a result of heavy rainfall during the growing season, especially in June and September. Differences between the studied parameters were statistically significant. The results of the five years showed that the yield and quality of grapes were in direct relation with the weather conditions in certain years of experiments.