Doctoral Advisor Washington State University Pullman, Washington
The physiological age of potato seed tubers significantly influences plant emergence, apical dominance, tuber set, and tuber size, all of which play a critical role in determining the overall value of the crop. While existing research explores the effects of storage conditions and planting practices on seed tuber performance, research specifically targeting the optimization of physiological aging treatments to enhance tuber size distribution and set under specific environmental conditions remains limited. To address these gaps, cvs. Caribou Russet, Dakota Russet, and Laona were subjected to varying storage durations and temperatures to increase the physiological age before planting. They were aged using modest temperature treatments (15.6°C) to achieve 450, & 900-degree days (DD) at the WSU Research Facilities, then stored (4°C) until planting the following spring in Othello, Washington, for two years (2023 & 2024). Field trials assessed plant emergence, stem number, and row closure/final stands, while post-harvest analyses evaluated yield (total and marketable) and average tuber size distribution. General findings show that 450DD treatments enhanced yield and promoted relative crop value for processing by as much as 32% (2023, Caribou Russet, 450DD). Extending tuber aging to 900DD lead to reductions in total yield and marketable size categories, though this was cultivar-dependent, indicating that prolonged aging could detrimentally affect productivity. Additionally, this work identifies practical methods for growers to apply aging treatments in bulk storages to ensure consistent and scalable adoption. Overall, the findings suggest the importance of tailoring aging practices to maximize yield potential, economic returns, and crop performance.
