The Effect of Seed-Tuber Physiological Age and Cultivar on Early Potato Production

Enhancing physiological aging of seed‐potatoes has the potential to substantially affect production, especially for short‐season growing areas. This study analysed the effect of seed‐tuber age and cultivar, jointly, to identify the combination for optimum early crop production, based on field experiments conducted at two locations in Nova Scotia, Canada. The potato cultivars Superior, AC‐Novachip, Niska, and Yukon Gold were aged by exposing seeds stored at 4 °C to warming periods of 0, 242 (3 weeks), and 484 (6 weeks) day‐degrees, prior to planting. Cultivar and age levels were completely randomized within each location and replicated four times. Harvest periods at 65, 80 and 95 days after planting (DAP) were analysed as an unbalanced split‐plot factorial, with year as a random blocking factor, location as a whole plot treatment, and cultivar and age crossed as subplot treatments. Total yield and marketable yield from Yukon Gold improved with physiological age when harvested early at 65 and 80 DAP, while that from AC‐Novachip improved when aged only 3 weeks. Niska was not affected by age. Overall, AC‐Novachip was consistently better than the remaining cultivars, regardless of age. The best treatment combination that maximized marketable yield was Yukon Gold aged 6 weeks planted at a commercial farm and harvested 95 DAP. For early harvest (65 DAP), however, AC‐Novachip aged 3 weeks and Yukon Gold aged 6 weeks generated the highest yields. Niska and Superior generated lower yield and higher culls.