Aims: Under global warming, the desynchrony between technology maturity and phenolic maturity of wine grapes is a worthy concern. Late winter pruning (LWP) has been proved to be an effective way to delay the grape phenological stages. The aim of this study was to evaluate the effects of LWP at different phenological stages (based on Baillod & Baggiolini system) on the delay of the grape ripening, on vine yield components as well as on berry composition, among others, the anthocyanin to sugar ratio.
Methods and results: The two-year (2015 and 2016) trial was conducted in Rioja wine region (North of Spain) on Maturana vines and in each year, four pruning treatments were carried out taking apical buds/shoots as reference: (1) winter pruning at stage A (WPA; dormant bud); (2) LWP at stage C (LWPC; green shoot tip) in 2015 and at stage F (LWPF; inflorescence clearly visible) in 2016; (3) LWP at stage G (LWPG; inflorescences separated); (4) LWP at stage H (LWPH; flowers separated). LWPC failed to delay the late phenological stages and did not exert important influence on vine yield and berry composition. LWPG and LWPH succeeded to delay all the phenological stages of grapes to a great extent and created a considerably cooler and longer ripening period compared to WPA. Vine yield was not affected by LWPF and was reduced significantly (averagely by 41%) by LWPG. LWPH lead to great losses in yield (averagely by 67%), especially in 2015. LWPG did not change the fruit composition while LWPH increased the ratio of anthocyanin to sugar and helped to maintain a relatively high level of acidity in berries.
Conclusions: The primary cause of the decline in production seems to be the losses of flowers and/or the reduction in fruit set percentage in the current season, instead of the losses in inflorescences within buds in the previous season. For Maturana grapes, LWP after the stage F would reduce the vine yield and could be applied as an alternative to the time consuming cluster thinning to meet the needs of yield control. Delaying the winter pruning to stage H could improve the fruit quality in spite of the greater risk of botrytis and a serious decline in production.Significance and impact of the study: The outcomes of this research open a door for the winegrowers to realize the yield control in a simple way. Also, for those who only pursue wines of top quality (regardless of production), a very late winter pruning might provide them with high-quality grapes. Moreover, as can be seen obviously from our results, viticulturists could postpone the budburst date to whatever extent they wish thus reducing the risk of spring frost injury to zero, though this point is not our focus in the study.
Antcliff A., Webster W., May P., 1957. Studies on the Sultana vine. V. Further studies on the course of bud burst with reference to time of pruning. Crop and Pasture Science 8: 15-23.
Baillod M. & Baggiolini M., 1993. Les stades repères de la vigne. Revue Suisse de Viticulture Arboriculture Horticulture 25: 10-12.
Balda P., Palacios A., Carrillo D., Zaldivar E., Borinaga I., Martínez de Toda F., 2013. Expresión de pirazinas en Maturana Tinta de Navarrete: efectos de la radiación solar. La Semana vitivinícola 3412: 1926-1933.
Bennett J., Jarvis P., Creasy G.L., Trought M.C., 2005. Influence of defoliation on overwintering carbohydrate reserves, return bloom, and yield of mature Chardonnay grapevines. American Journal of Enology and Viticulture 56: 386-393.
Champagnol F., 1984. Elements of the physiology of the vine and of general viticulture. Impr. Dehan, Montpellier.
Coombe B., 1995. Growth stages of the grapevine: adoption of a system for identifying grapevine growth stages. Australian Journal of Grape and Wine Research 1: 104-110.
Friend A.P. & Trought M.C., 2007. Delayed winter spur-pruning in New Zealand can alter yield components of Merlot grapevines. Australian Journal of Grape and Wine Research 13: 157-164.
Frioni T., Tombesi S., Silvestroni O., Lanari V., Bellincontro A., Sabbatini P., Gatti M., Poni S., Palliotti A., 2016. Post-Budburst spur-pruning reduces yield and delays fruit sugar accumulation in Sangiovese in central Italy. American Journal of Enology and Viticulture 67: 419-425.
Gatti M., Pirez F.J., Chiari G., Tombesi S., Palliotti A., Merli M.C., Poni S., 2016. Phenology, canopy aging and seasonal carbon balance as related to delayed winter pruning of Vitis vinifera L. cv. Sangiovese grapevines. Frontiers in plant science 7: Article 659.
Gu S., Jacobs S., McCarthy B., Gohil H., 2012. Forcing vine regrowth and shifting fruit ripening in a warm region to enhance fruit quality in ‘Cabernet Sauvignon’ grapevine (Vitis vinifera L.). The Journal of Horticultural Science and Biotechnology 87: 287-292.
He F., Mu L., Yan G.-L., Liang N.-N., Pan Q.-H., Wang J., Reeves M.J., Duan C.-Q., 2010. Biosynthesis of anthocyanins and their regulation in colored grapes. Molecules 15: 9057-9091.
Howell G.S. & Wolpert J.A., 1978. Nodes per cane, primary bud phenology, and spring freeze damage to Concord grapevines. A preliminary note. American Journal of Enology and Viticulture 29: 229-232.
Iland P., Bruer N., Edwards G., Weeks S., Wilkes E., 2004. Chemical analysis of grapes and wine: techniques and concepts. Patrick Iland Wine Promotions, Campbelltown, SA, Australia.
Iland P. & Gago P., 2002. Australian wine: Styles and tastes. Patrick Iland Wine Promotions, Campbelltown, SA, Australia.
Jackson R.S., 2009. Wine tasting: a professional handbook. 2nd edition, Elsevier Academic Press.
Jones G.V., White M.A., Cooper O.R., Storchmann K., 2005. Climate change and global wine quality. Climatic change 73: 319-343.
Keller M., 2010. Managing grapevines to optimise fruit development in a challenging environment: a climate change primer for viticulturists. Australian Journal of Grape and Wine Research 16: 56-69.
Keller M., 2015. The science of grapevines: anatomy and physiology. 2nd edition. Elsevier Academic Press, London.
Kliewer W.M. & Dokoozlian N.K., 2005. Leaf area/crop weight ratios of grapevines: influence on fruit composition and wine quality. American Journal of Enology and Viticulture 56: 170-181.
Lavee S. & May P., 1997. Dormancy of grapevine buds - facts and speculation. Australian Journal of grape and wine research 3: 31-46.
Martínez de Toda F., Sancha J., Zheng W., Balda P., 2014. Leaf area reduction by trimming, a growing technique to restore the anthocyanins: sugars ratio decoupled by the warming climate. VITIS 53 (4): 189-192.
Martin S.R. & Dunn G.M., 2000. Effect of pruning time and hydrogen cyanamide on budburst and subsequent phenology of Vitis vinifera L. variety Cabernet Sauvignon in central Victoria. Australian Journal of Grape and Wine Research 6: 31-39.
May P., 2000. From bud to berry, with special reference to inflorescence and bunch morphology in Vitis vinifera L. Australian Journal of Grape and Wine Research 6: 82-98.
Mori K., Goto-Yamamoto N., Kitayama M., Hashizume K., 2007. Loss of anthocyanins in red-wine grape under high temperature. Journal of Experimental Botany 58: 1935-1945.
Mori K., Sugaya S., Gemma H., 2005. Decreased anthocyanin biosynthesis in grape berries grown under elevated night temperature condition. Scientia Horticulturae 105: 319-330.
OIV, 2014. Compendium of International Methods of Analysis of Wines and Musts. Bull OIV, Paris.
Palliotti A., Panara F., Silvestroni O., Lanari V., Sabbatini P., Howell G., Gatti M., Poni S., 2013. Influence of mechanical postveraison leaf removal apical to the cluster zone on delay of fruit ripening in Sangiovese (Vitis vinifera L.) grapevines. Australian Journal of Grape and Wine Research 19: 369-377.
Palliotti A., Tombesi S., Silvestroni O., Lanari V., Gatti M., Poni S., 2014. Changes in vineyard establishment and canopy management urged by earlier climate-related grape ripening: A review. Scientia Horticulturae 178: 43-54.
Parkin R. & Turkington C., 1980. Late pruning improves wine quality. Agricultural Gazette of New South Wales 91: 36-37.
Pirie A. & Mullins M., 1977. Interrelationships of sugars, anthocyanins, total phenols and dry weight in the skin of grape berries during ripening. American Journal of Enology and viticulture 28: 204-209.
Poni S., Intrieri C., Silvestroni O., 1994. Interactions of leaf age, fruiting, and exogenous cytokinins in Sangiovese grapevines under non-irrigated conditions. I. Gas exchange. American journal of enology and viticulture 45: 71-78.
Reynier A., 2002. Manual de viticultura. Ediciones Mundi Prensa, Madrid.
Sadras V.O. & Moran M.A., 2012. Elevated temperature decouples anthocyanins and sugars in berries of Shiraz and Cabernet Franc. Australian Journal of Grape and Wine Research 18: 115-122.
Schultz H., 2000. Climate change and viticulture: a European perspective on climatology, carbon dioxide and UV-B effects. Australian Journal of grape and wine research 6: 2-12.
Smart R. & Robinson M., 1991. Sunlight into wine: a handbook for winegrape canopy management. Winetitles, Australia.
Trought M., Howell G., Cherry N.J., 1999. Practical considerations for reducing frost damage in vineyards. Report to New Zealand Winegrowers.
Vasconcelos M.C., Greven M., Winefield C.S., Trought M.C., Raw V., 2009. The flowering process of Vitis vinifera: a review. American Journal of Enology and Viticulture 60: 411-434.
Weyand K.M. & Schultz H.R., 2006. Long-term dynamics of nitrogen and carbohydrate reserves in woody parts of minimally and severely pruned Riesling vines in a cool climate. American journal of enology and viticulture 57: 172-182.
Zheng W., del Galdo V., García J., Balda P., Martínez de Toda F., 2017. Use of Minimal Pruning to Delay Fruit Maturity and to Improve Berry Composition under Climate Change. American Journal of Enology and Viticulture 68 : 136-140.