Harvest Timing and Cold Storage Temperature Modulate Carbohydrate Metabolism, Dormancy, and Sprouting in Seed Potato Tubers

The physiological quality of seed potato tubers during storage is important for maintaining their subsequent performance. This study evaluated the effects of harvest timing and storage temperature on Asterix and Orchestra seed potato tubers produced in Rio Paranaíba, Brazil. Tubers were harvested on August 10 and September 15, 2024, stored at 1.5, 3.5, or 6.5 °C, and evaluated for up to 120 and 90 days, respectively. Sprouting, mass loss, starch, reducing sugars, and total soluble sugars were assessed during storage. Storage at 1.5 °C was the most effective in delaying sprout development in both cultivars, whereas greater sprouting generally occurred at 6.5 °C. Mass loss and carbohydrate concentrations showed more complex responses depending on harvest timing, storage temperature, and duration. These results demonstrate that integrating harvest timing and storage temperature is important for managing seed potato physiological quality and storage potential.