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Our study found that storage temperature, storage atmosphere and growing region interactively affect the probability of internal browning disorder in `McIntosh' apples (Malus domestica Borkh.). Higher incidence of internal browning occurred in apples stored for 6 months at 1 °C (34 °F) in controlled atmosphere (CA) with 2.5% O₂ + 1.5% CO₂ or in CA with 1.0% O₂ + 0.5% CO₂ than apples stored at 1 °C in air or stored at 3 °C (37 °F) in air or CA conditions. The magnitude of the incidence of internal browning varied among apples harvested from different growing regions. Apples from London, Ontario, Canada were less tolerant to these two storage conditions and therefore greater number of fruit developed internal browning than apples from other regions. In addition, apples from the London growing region and stored at 1 °C in CA with 1.0% O₂ + 0.5% CO₂ had greater probability of internal browning than apples stored at 1 °C in CA with 2.5% O₂ + 1.5% CO₂. However, there was no difference between these two CA storage conditions in causing internal browning among apples harvested from other three growing regions. Few apples showed internal browning when they were stored at 3 °C, no matter of what storage atmosphere was used. Therefore, internal browning disorder can be avoided or significantly reduced by storing apples at 3 instead of 1 °C, in these two CA conditions. Internal browning disorder will not be a risk if apples are stored in air at 1 or 3 °C.

Sexual potato (Solanum tuberosum L.) seeds require many months of afterripening in dry storage to completely lose dormancy and germinate readily at >25C. We examined the relationship between storage temperature and seed dormancy, as assessed by the percentage of germination after 4 days. Two F₁ hybrid lots of `Desiree' × 7XY.1 were used; one seed lot was produced by carefully removing half of the developing tubers from the mother plant during seed development, and the control remained undisturbed. Seeds were stored with 3.4% moisture (dry-weight basis) at 10, 20, 30, 40, and 50C and were tested eight times during 29 months for daily germination at 27/40C (21/3 h) for the first 8 days, followed by 6 days at 17C. After 29 months of storage, final germination was <97% only when control seeds were stored at 50C, in which germination was 72%. Germination after 4 days increased curvilinearly with increasing storage temperature, and both seed lots similarly lost dormancy (germination >90%) after 10 months at 40C. Optimum germination levels were maintained after 29 months at 40C. Seeds stored at 50C never completely lost dormancy, and after 7 months of storage, germination at 4 days gradually decreased to zero. Dormancy was eventually lost after 29 months in most seeds stored at <40C, and differences between seed lots suggest that removing tubers from the mother plant increased dormancy. We conclude that dry potato seeds can be safely afterripened at temperatures up to 40C; lower temperatures slow the rate of dormancy loss, and higher ones are detrimental to seed quality.