Bud load levels and leaf removal in Vitis vinifera L. ‘Sultana’
Turcan Teker is a viticulturist who works in the Republic of Turkey Ministry of Agriculture and Forestry, Directorate General of Agricultural Research and Policies, Viticulture Research Institute in Manisa. His research focused on canopy management of grapevines, berry shrivel, grapevine physiology, and optimization of raisin quality and quantity. He graduated with a BS from Ankara University, Faculty of Agriculture, Department of Horticulture (2009). He completed his MS in viticulture science at the Graduate School of Natural and Applied Sciences, Ankara University. He is currently studying for his PhD under the supervision of Prof. Dr. Ahmet Altındişli at the Graduate School of Natural and Applied Sciences, Ege University. Turcan has completed his field research and is focused on completing his thesis. Berry shrivel is the most economically important and frequent problem in grapes in the Aegean Region. Every year, growers complain about this issue to extension and research institutions. Extreme bud load and leaf removal may cause berry shrivel. The recommendations for ‘Sultana’ production is to have 15 buds m-2 (90 buds on canes) and to remove 25% of the leaves. Yet, some growers leave a larger number of buds (150-180 buds) on the canes to obtain more bunches. Turcan’s research examined the effect of bud load and leaf removal treatments on the physiology of grapevines, yield, berry quality, and the occurrence of berry shrivel. Two different bud load treatments (15 and 30 buds m-2) and two different leaf removal treatments (25 and 50%) were applied to the vines. Leaf removal treatments were performed as a summer pruning approximately one month before veraison (grape ripening). During harvest, berry samples were taken separately from the upper and lower side of bunches for analysis. Berries from each treatment were analyzed for mineral compounds, yield, and quality. Significant differences in berry quality and other traits between optimum and extreme bud load applications were detected. Over-loaded vines were characterized by small berries, soft berry texture, reduced bud fruitfulness, and crop yields. There was no significant difference (p<0.05) between the yield of the treatments due to the quantity of many clusters in 30 buds m-2 treatment. 62.8% more berries per bunch were obtained in 30 buds m-2 treatment as compared with the 15 buds m-2 treatment. However, bunch weight decreased by 28.7%. The increased number of bunches (almost 75-87 bunches per vine) accelerated the occurrence of shriveled berries. This difficulty was observed in the 30 buds m-2 treatment, and both 25 and 50% leaf removal treatments. However, shrivel was not found in the 15 buds m-2 treatment. Berry weight decreased as bud load on the grapevine increased, and more leaves were removed (50%) on shoots. Bud load treatments also affected berry width and length values.
Turcan Teker won an ISHS Young Minds Award for the best poster presentation at the International Symposium on Viticulture: Primary Production and Processing at IHC2018 in Turkey in August 2018.
Turcan Teker, Viticulture Research Institute, Horozkoy Cad. P.K. 12 No 268, 45125 Manisa Yunusemre, Turkey, e-mail: firstname.lastname@example.org
The article is available in Chronica Horticulturae