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ARS Home » Pacific West Area » Wenatchee, Washington » Physiology and Pathology of Tree Fruits Research » Research » Publications at this Location » Publication #415146
Research Project: Enhancement of Apple, Pear, and Sweet Cherry Quality

Location: Physiology and Pathology of Tree Fruits Research

Title: SUNIndx: Visual identification of sun stressed-areas of the fruit using a reflectance index (Sun Index) from hyperspectral images to predict sunscald-risk postharvest on ‘Granny Smith’ apples

Author
item MOGOLLON, RENE - Washington State University
item Rudell, David
item TORRES, CAROLINA - Washington State University

Submitted to: Postharvest Biology and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/12/2024
Publication Date: 7/25/2024
Citation: Mogollon, R., Rudell Jr, D.R., Torres, C. 2024. SUNIndx: Visual identification of sun stressed-areas of the fruit using a reflectance index (Sun Index) from hyperspectral images to predict sunscald-risk postharvest on ‘Granny Smith’ apples. Postharvest Biology and Technology. 27. Article 101828. https://doi.org/10.1016/j.softx.2024.101828.
DOI: https://doi.org/10.1016/j.softx.2024.101828

Interpretive Summary: Sunscald is an apple peel disorder that may result from elevated light and heat in the orchard. The disorder is absent at harvest and typically only appears after 2 months of cold storage often leading to significant annual losses. This software (SUNIndx) was developed and to assess at harvest risk of individual ‘Granny Smith’ apples of developing sunscald during storage. Here, SUNIndx is released as a means to detect sun stress for this purpose as well as other fruit commodities.

Technical Abstract: Sunscald is a postharvest peel disorder on apples and pears caused by sun stress during fruit growth. It has been shown that a newly developed sun index using wavelength associated with chlorophylls and carotenoids can be used to detect sun-stressed areas on the fruit and use it as a sun-risk predictor at harvest for sunscald development postharvest. SUNIndx is a group of functions coded in Python to process spectral data, calculate the index, visualize it in the hyperspectral image, and generate a sunscald-risk category of ‘Granny Smith’ apples at harvest. This software can be manipulated and tailored to detect sun stress in different commodities based on hyperspectral images.