Skip to main content
ARS Home » Pacific West Area » Wapato, Washington » Temperate Tree Fruit and Vegetable Research » Research » Publications at this Location » Publication #427121
Research Project: Potato Germplasm Development for Improved Sustainability, Disease Resistance, Nutrition, and Quality

Location: Temperate Tree Fruit and Vegetable Research

Title: Screening breeding lines for resistance to greening and glycoalkaloid spikes

Author
item Navarre, Duroy
item HNINSI, MOE - Washington State University
item Feldman, Maximilian
item Cimrhakl, Launa

Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2025
Publication Date: 10/27/2025
Citation: Navarre, D.A., Hninsi, M., Feldman, M.J., Cimrhakl, L.L. 2025. Screening breeding lines for resistance to greening and glycoalkaloid spikes. American Journal of Potato Research. 102:535. https://doi.org/10.1007/s12230-025-10020-y.
DOI: https://doi.org/10.1007/s12230-025-10020-y

Interpretive Summary:

Technical Abstract: Potatoes exposed to light can develop various visual defects such as greening and other changes in coloration. These changes can increase culling and negatively impact sustainability. Light can also increase the amounts of glycoalkaloids in potatoes, which at high levels can have toxic effects if consumed. USDA and Washington State University researchers treated tubers from over 50 cultivars with light and observed major changes in coloration, including yellow-skin potatoes turning purple or green. The cultivars varied in how much they greened. Greening is considered a defect because it is assumed to indicate that glycoalkaloids have increased. However, in our study light exposure always led to an increase in greening, but often did not lead to any increase in glycoalkaloids. We showed that chlorophyll (responsible for the green color), carotenoids (responsible for yellow color and health promoting in the diet) and glycoalkaloids (toxic at high concentrations) all can be induced by light, but each can increase and the others not increase, despite being products of the same general metabolic pathway. All new potato cultivars released by US breeding programs have safe levels of glycoalkaloids, so the major concern about glycoalkaloids in 2025 is the possibility that glycoalkaloid levels might spike to toxic levels in response to poorly understood environmental triggers and that this is largely unpredictable. We developed a simple screen that can be used to assess whether a new breeding line is resistant to large spikes in glycoalkaloids. We also suggest a way to screen lines for resistance to greening and other color changes. These findings can reduce waste and further increase the quality of potatoes.