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IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2013 9 GiESCO 2013 – Session 4: Environment–climate and soil 9 Sunburn physiology phenotypization by reflectance

Sunburn physiology phenotypization by reflectance

Abstract

Sunburn could affect grape quality both for chemical modifications and visual impact of the browning. Different varietal behaviors could support the selection of cultivars in relation to environmental and cultural conditions. In this study, optical properties of 17 white grapes were investigated in the visible and near infrared regions using a noninvasive instrument. Browning was induced by exposing clusters to sunlight. All the samples were treated the same day in the last phase of fruit ripening. Chlorophylls and carotenoids were estimated using several reflectance indexes. Differences between control and exposed spectra underlined mainly the loss in chlorophyll, the formation of brown compounds (λmax 540 nm), no changes in carotenoid content and a probable tissue structural variations (modifications in the NIR reflectance region). A positive correlation among chlorophyll concentration and browning symptoms appeared. Two different groups were found supporting that carotenoids could affect the browning symptoms at similar chlorophyll levels.

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Publication date: 07/09/2026

Issue: GiESCO 2013

Type: Poster

Authors

Letizia Rocchi1, Eugenio Guffanti1, Gabriele Cola1, Osvaldo Failla1, Laura Rustioni1

1 Università degli Studi di Milano, CIRIVE – Centro Interdipartimentale di ricerca per l’innovazione in Viticoltura ed Enologia, via Celoria 2, I-20133 Milano, Italy

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Keywords

sunburn, browning, reflectance, spectrum, pigments, grapevine

Tags

GiESCO | GiESCO 2013 | IVES Conference Series

Citation

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