Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples

The environmental factors that influence cider apple fruit quality, particularly bitter and astringent polyphenols, are not well understood. Five experiments were conducted to investigate how sunlight affects fruit and juice quality. In three studies, shade cloth was placed over entire trees or indi...

Full description

Bibliographic Details
Main Authors: Adam Duerr Karl, Gregory Michael Peck
Format: Article
Language:English
Published: MDPI AG 2022-10-01
Series:Horticulturae
Subjects:
Online Access:https://www.mdpi.com/2311-7524/8/11/993
_version_ 1797468117903867904
author Adam Duerr Karl
Gregory Michael Peck
author_facet Adam Duerr Karl
Gregory Michael Peck
author_sort Adam Duerr Karl
collection DOAJ
description The environmental factors that influence cider apple fruit quality, particularly bitter and astringent polyphenols, are not well understood. Five experiments were conducted to investigate how sunlight affects fruit and juice quality. In three studies, shade cloth was placed over entire trees or individual branches at different phenological stages, durations, and opacities. Influence of canopy microclimate was investigated by harvesting fruit from different sections of the tree canopy. In a final study, opaque paper bags were placed over fruit three weeks after full bloom (WAFB) until harvest. Polyphenol concentrations increased rapidly during the first five WAFB and were diluted as fruit grew larger. At harvest, fruit from unshaded trees had 32% greater total polyphenol concentrations and were 11% larger than trees shaded 1–5 WAFB. Shading branches later in the growing season reduced yield but had a modest and inconsistent reduction on polyphenol concentrations. Juice from fruit harvested from the top of the tree canopy had 33% greater polyphenol concentrations and 14% greater soluble solid concentrations than juice from the interior of the canopy. Bagging fruit had inconsistent impacts on polyphenol concentrations. We hypothesize that there is a source sink relationship between carbohydrate availability and polyphenol synthesis in apple fruit during the early stages of fruit development when most polyphenols are produced. Additionally, greater carbohydrate availability in canopies with greater sunlight exposure resulted in larger fruit and improved juice quality from a cider making perspective.
first_indexed 2024-03-09T19:03:00Z
format Article
id doaj.art-d82c508642b042be988c2feed7dc1ba1
institution Directory Open Access Journal
issn 2311-7524
language English
last_indexed 2024-03-09T19:03:00Z
publishDate 2022-10-01
publisher MDPI AG
record_format Article
series Horticulturae
spelling doaj.art-d82c508642b042be988c2feed7dc1ba12023-11-24T04:52:29ZengMDPI AGHorticulturae2311-75242022-10-0181199310.3390/horticulturae8110993Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider ApplesAdam Duerr Karl0Gregory Michael Peck1School of Integrative Plant Science, Horticulture Section, Cornell University, Plant Science Building, Ithaca, NY 14853, USASchool of Integrative Plant Science, Horticulture Section, Cornell University, Plant Science Building, Ithaca, NY 14853, USAThe environmental factors that influence cider apple fruit quality, particularly bitter and astringent polyphenols, are not well understood. Five experiments were conducted to investigate how sunlight affects fruit and juice quality. In three studies, shade cloth was placed over entire trees or individual branches at different phenological stages, durations, and opacities. Influence of canopy microclimate was investigated by harvesting fruit from different sections of the tree canopy. In a final study, opaque paper bags were placed over fruit three weeks after full bloom (WAFB) until harvest. Polyphenol concentrations increased rapidly during the first five WAFB and were diluted as fruit grew larger. At harvest, fruit from unshaded trees had 32% greater total polyphenol concentrations and were 11% larger than trees shaded 1–5 WAFB. Shading branches later in the growing season reduced yield but had a modest and inconsistent reduction on polyphenol concentrations. Juice from fruit harvested from the top of the tree canopy had 33% greater polyphenol concentrations and 14% greater soluble solid concentrations than juice from the interior of the canopy. Bagging fruit had inconsistent impacts on polyphenol concentrations. We hypothesize that there is a source sink relationship between carbohydrate availability and polyphenol synthesis in apple fruit during the early stages of fruit development when most polyphenols are produced. Additionally, greater carbohydrate availability in canopies with greater sunlight exposure resulted in larger fruit and improved juice quality from a cider making perspective.https://www.mdpi.com/2311-7524/8/11/993applecarbohydrateciderpolyphenolphenologysunlight
spellingShingle Adam Duerr Karl
Gregory Michael Peck
Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
Horticulturae
apple
carbohydrate
cider
polyphenol
phenology
sunlight
title Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
title_full Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
title_fullStr Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
title_full_unstemmed Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
title_short Greater Sunlight Exposure during Early Fruit Development Increases Polyphenol Concentration, Soluble Solid Concentration, and Fruit Mass of Cider Apples
title_sort greater sunlight exposure during early fruit development increases polyphenol concentration soluble solid concentration and fruit mass of cider apples
topic apple
carbohydrate
cider
polyphenol
phenology
sunlight
url https://www.mdpi.com/2311-7524/8/11/993
work_keys_str_mv AT adamduerrkarl greatersunlightexposureduringearlyfruitdevelopmentincreasespolyphenolconcentrationsolublesolidconcentrationandfruitmassofciderapples
AT gregorymichaelpeck greatersunlightexposureduringearlyfruitdevelopmentincreasespolyphenolconcentrationsolublesolidconcentrationandfruitmassofciderapples