Research Article

Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System

Number: 1 June 8, 2026

Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System

Abstract

This study evaluated the effects of basal leaf removal at different phenological stages on yield, fruit quality, phytochemical composition, and winter bud physiology of the Karaerik grape cultivar under the Baran training system. Basal leaf removal was applied by removing five basal leaves at full flowering, pea-size berry, and veraison, and compared with an untreated control. The experiment was carried out over two consecutive growing seasons (2023 and 2024) using a randomized block design. The timing of leaf removal significantly influenced yield components and berry characteristics. Control vines produced the highest fresh grape yield (8.98 kg vine⁻¹), whereas vines defoliated at full flowering showed a moderate yield reduction (7.43 kg vine⁻¹). Despite this reduction, full flowering treatment substantially decreased cluster compactness (OIV-204: 4.58) compared with the control (7.58) and reduced the incidence of cracked and decayed berries by approximately 80%. Early defoliation also promoted berry growth, resulting in the highest single berry weight (5.91 g). Technological maturity parameters were positively affected by early leaf removal. The full flowering treatment resulted in the highest total soluble solids (19.07%), maturity index (27.42), and total phenolic content (504.57 mg L⁻¹). Moreover, leaf removal at full flowering and at pea-size berry significantly increased soluble carbohydrate concentrations in winter buds and reduced primary bud cold injury and necrosis. Overall, basal leaf removal at full flowering emerged as an effective vineyard management strategy to improve fruit quality, enhance phytochemical accumulation, and increase winter bud cold tolerance in Karaerik grapes cultivated under the Baran training system.

Keywords

Supporting Institution

No financial support was received for this study.

Ethical Statement

Ethical approval is not required for this study.

Thanks

I would like to express my gratitude to the Erzincan Horticultural Research Institute Directorate and its staff for their support in conducting this study.

References

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Details

Primary Language

English

Subjects

Oenology and Viticulture

Journal Section

Research Article

Publication Date

June 8, 2026

Submission Date

January 12, 2026

Acceptance Date

April 27, 2026

Published in Issue

Year 2026 Number: 1

APA
Geçim, T., Bozkurt, A., & Kalkan, N. N. (2026). Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System. Yuzuncu Yıl University Journal of Agricultural Sciences, 1, 1861975. https://doi.org/10.29133/yyutbd.1861975
AMA
1.Geçim T, Bozkurt A, Kalkan NN. Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System. YYU J AGR SCI. 2026;(1):1861975. doi:10.29133/yyutbd.1861975
Chicago
Geçim, Tevhit, Abdurrahim Bozkurt, and Nalan Nazan Kalkan. 2026. “Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System”. Yuzuncu Yıl University Journal of Agricultural Sciences, no. 1: 1861975. https://doi.org/10.29133/yyutbd.1861975.
EndNote
Geçim T, Bozkurt A, Kalkan NN (June 1, 2026) Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System. Yuzuncu Yıl University Journal of Agricultural Sciences 1 1861975.
IEEE
[1]T. Geçim, A. Bozkurt, and N. N. Kalkan, “Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System”, YYU J AGR SCI, no. 1, p. 1861975, June 2026, doi: 10.29133/yyutbd.1861975.
ISNAD
Geçim, Tevhit - Bozkurt, Abdurrahim - Kalkan, Nalan Nazan. “Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System”. Yuzuncu Yıl University Journal of Agricultural Sciences. 1 (June 1, 2026): 1861975. https://doi.org/10.29133/yyutbd.1861975.
JAMA
1.Geçim T, Bozkurt A, Kalkan NN. Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System. YYU J AGR SCI. 2026;:1861975.
MLA
Geçim, Tevhit, et al. “Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System”. Yuzuncu Yıl University Journal of Agricultural Sciences, no. 1, June 2026, p. 1861975, doi:10.29133/yyutbd.1861975.
Vancouver
1.Tevhit Geçim, Abdurrahim Bozkurt, Nalan Nazan Kalkan. Effects of Leaf Removal at Different Phenological Stages on Yield, Quality, and Growth of Karaerik Grapevines Trained in the Baran System. YYU J AGR SCI. 2026 Jun. 1;(1):1861975. doi:10.29133/yyutbd.1861975
Creative Commons License
Yuzuncu Yil University Journal of Agricultural Sciences by Van Yuzuncu Yil University Faculty of Agriculture is licensed under a Creative Commons Attribution 4.0 International License.