Effect of High Temperature during Intermittent Low-temperature Storage of Nursery Plants on Flowering Dates of Strawberry

Abstract

To clarify the inhibitory effect of high temperatures under natural light conditions during intermittent low-temperature storage (ILTS) for flower induction in June-bearing strawberries, high temperature treatments were conducted before or at 3 specified times of low-temperature storage for 3 days (15°C in dark). Among the three cultivars that exhibited different flowering behaviors on forcing culture, ‘Sachinoka’ was found to be the most sensitive to high temperatures, followed by ‘Tochiotome’ and ‘Sanukihime’. The effect of ILTS was the lowest on ‘Sachinoka’ when the daily average temperature was above 26°C under natural light conditions. However, there was only a minor inhibitory effect on ‘Sanukihime’ and ‘Tochiotome’, even when the temperature was high. In ‘Sachinoka’ and ‘Sanukihime’, the effect of ILTS tended to decrease by minor differences between the day and night temperatures when the mean temperature was 28°C. Additionally, the efficiency of ILTS did not decrease after encountering high-temperature conditions for 3 days.