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Balanced pruning is used to manage vegetative vigor and fruit load to optimize yield and fruit quality in most of fruit species. The objective of this study was to determine the bud viability, yield, and fruit quality potential of four grapevine cultivars using three pruning strategies. Four cold climate grapevine cultivars- -Brianna, Frontenac, La Crescent, and Marquette--were tested with spur (SP), short cane (SC), and spur plus short cane (SPSC) pruning treatments in 2018, 2019, and 2020. The SP treatment was 10 two-bud spurs per vine, SC was five four-bud short canes, and SPSC vines had four SP and three SC. Soluble solids, pH, and total acid were measured for individual bud positions on all spurs, canes or spurs and canes on each treated vine. Yield in all cultivars was lower in 2019 and 2020 due to severe winter cold. The greatest bud viability across the three years in each cultivar was achieved in Frontenac and Marquette with SP, followed by Brianna with SP and SC and La Crescent with SPSC pruning treatments. The highest yield for pruning treatments was Brianna with SC, Frontenac with SPSC, La Crescent with SC and SPSC, and Marquette with SP and SC pruning treatments. Brianna had the greatest fruit soluble solids and pH in SC pruning treatment. In contrast, Frontenac and La Crescent had greatest fruit soluble solids and lowest total acid with SP pruning treatment. Marquette showed similar soluble solids across all pruning treatments; however, pH was greatest in SC and total acid was lower in SP and SC than in SPSC. The pruning strategy impacted bud viability, yield and fruit quality measures most differently in Brianna and La Crescent; however, with these vigorous vines the SC could provide greater yield. In contrast, in Marquette and Frontenac bud viability, yield, and fruit quality were generally favored with SP. Results of this study indicate different pruning techniques, which taken in consideration with winter injury, can be used to optimize each grape cultivar yield and fruit quality. [ABSTRACT FROM AUTHOR]

The cultivated grapevine (Vitis vinifera L.) is a fruit crop of enormous economic importance with over eight million hectares planted in vineyards worldwide. Table grapes and wines represent a considerable share of the economy in many grape and wine-producing countries. During the dormant, due to low temperatures and how to prepare grape for entrance in winter time, wood annual increases and buds may be adversely affected. The way how the vines passed by dormant period can affect the buds and wood viability and rooting ability of vine cuttings. In this study were tested on different culture substrates vine cuttings belonging to a noble variety and a hybrid vines: Merlot and Isabella. Noble grapes are a term used to describe the international variety of grapes that are most recognizable for the top quality wine they produce. In this paper was determinate total dry matter of vine cuttings, humidity of biological material, vine cuttings rooting capacity and viability status buds cuttings placed on three nutritional substrates.

Five grape varieties for red wines (Pinot noir, Mer lot, Cabernet Sauvignon, Syrah and Burgund mare) were tested in 2009-2010, in NW Romania (Râteçti wine-growing center), under two types of cultural technology: thinning and without thinning grapes. The work of fruit load standardization through thinning grapes has been made at the beginning of veraison (third decade of July in 2009 and the first decade of august in 2010). In this study, were made observations regarding temperatures during the period 2009-2010 and the level of critical temperature during winter, in order to establish the quantity of carbohydrates (g %) from vine shoots and bud viability (%). The experiment was a bifactorial series (cultivar x fruit load standardization) with five grape wine varieties grown and two different applied technologies: thinning and without thinning grapes. Regardless of the standardization of fruit load, Syrah variety distinguished with high carbohydrate values of string, obtained during the two years of testing (15.94 g %) meaning good adaptability of the variety to climatic conditions in the Răteşti wine area. The other four species showed significant differences from the Syrah variety, however, between them, the differences are insignificant. The two variants analyzed (thinning and no thinning) had a significant influence on the accumulation of reserve substances. The string bud viability was high (over 85 %) to all five species tested. [ABSTRACT FROM AUTHOR]

Bud viability after various defoliation frequency treatments was determined in the perennial bunchgrass Poa ligularis under arid field conditions from 2002 to 2005. Bud respiratory activity was examined on various stem base hierarchies using the tetrazolium test, as validated with the vital stain Evan's blue. The hypothesis of this work was that the total and viable axillary bud numbers on stem bases of all study stem base hierarchies are reduced as defoliation frequency increases. Interpretation of the results differed when they were expressed as a percentage rather than on a number per stem base basis. The total number of axillary buds per stem base was similar in all defoliation frequencies. When the results were expressed on a percentage basis, the order on stem bases having metabolically active buds was daughter tillers > stem bases with green tillers > stem bases without green tillers in all defoliation frequencies. The reverse order was found when considering dead buds. How the results are expressed thus deserves our attention when reporting results on bud viability in perennial grasses. An increased defoliation frequency increased the percentage of dead and dormant buds after the third or fourth defoliation of P. ligularis during the 1st study year. These percentages of bud viability, however, increased after the first defoliation during the 2nd study year. Bud viability was affected not only by the cumulative effects of defoliation but also by climatic variables throughout the seasons. However, our results show that P. ligularis can be defoliated up to twice a year without affecting bud viability, and thus its potential capacity for regrowth after defoliation. [ABSTRACT FROM AUTHOR]

During vine's repose period, temperature is the main stress factor, which influences plant growth and development, as well as the level and quality of next year's yield. In this paper, were made observations regarding temperatures during the year 2009 and the level of critic temperature during the winter of 2009-2010, in order to establish the quantity of carbohydrates from vine shoots and bud viability for several grape varieties: Muscat Ottonel, Sauvignon blanc, Traminer roz and Neuburger. The critic period for vine was in January, due to 7 consecutive days of frost. Carbohydrates content in vine shoots oscillated between 12.09 g% (Neuburger) and 13.25 g% (Muscat Ottonel). Best viability for bearing buds was register for Muscat Ottonel variety 59.56% and the lowest one for Neuburger variety 25.90%. At Neuburger variety, the highest percentage of viable buds is found in the upper third (37.29% main buds and 50% secondary buds). [ABSTRACT FROM AUTHOR]