Thesis
POTATO FIELD GREENING AND RESPONSE TO POTASSIUM FERTILIZATION IN THE COLUMBIA BASIN
Washington State University
Master of Science (MS), Washington State University
01/2021
DOI:
https://doi.org/10.7273/000005420
Handle:
https://hdl.handle.net/2376/118934
Abstract
Potato growers in the Columbia Basin of Washington State face unique production challenges. The region’s high yields come with significant input costs and distinctive agronomic problems. Tuber field greening, the physiological result of tuber exposure to sunlight, is estimated to cause 14 to 17 percent losses to the US potato industry annually. Greening can be exacerbated by an array of factors, including environmental conditions, genetics, and cultural practices. Three trials characterizing and addressing field greening were conducted in Othello, Washington in 2019 and 2020. Significant differences were realized between hill drag-off treatments for yield and percentage of green tubers of Umatilla Russet in 2019. In 2020, simulated canopy shading of Alturas significantly reduced the yield and percentage of green tubers. Tuber arrangement digs of five commonly grown cultivars revealed that the number of tubers within 5 cm of the soil surface varied by cultivar, with Russet Burbank setting the fewest tubers within that zone. Another major drain on grower profitability is fertilizer cost. Potassium (K) is required in high amounts to maximize potato yield and quality, but regional research on the subject is limited. In this study, potassium chloride (KCl) applications significantly increased total and marketable yields for both Russet Burbank and Clearwater Russet in 2020, with 444 kg K2O ha-1 the optimal rate. When trial years were averaged for both cultivars, processor grades, tuber size profiles, and average weight were significantly differentiated between KCl treatments. Post-harvest evaluations revealed that increasing KCl rates significantly reduced tuber specific gravity in both cultivars, while also reducing the percentage of brown center and black spot in Russet Burbank. When compared to the 0 kg K2O ha-1 control, both cultivars showed significant reductions in tuber russet development and skinning due to KCl addition.
Metrics
Details
- Title
- POTATO FIELD GREENING AND RESPONSE TO POTASSIUM FERTILIZATION IN THE COLUMBIA BASIN
- Creators
- Joseph Nathan Townsend
- Contributors
- Mark J Pavek (Advisor)Norman R Knowles (Committee Member)Carrie H Wohleb (Committee Member)
- Awarding Institution
- Washington State University
- Academic Unit
- Department of Horticulture
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University
- Number of pages
- 76
- Identifiers
- 99900592256501842
- Language
- English
- Resource Type
- Thesis