Effect of low-temperature and short-photoperiod treatment during a high-temperature season on flower bud formation and generation acceleration of short-day strawberry.

摘要

Floral induction in strawberry is generally influenced by thermo-photoperiod and several agronomic and nutritional factors. This study was conducted to determine the environmental and plant physiological conditions for inducing flower bud formation during the hot and long-day season. The progeny from a varietal cross of 'Johong' x 'Sachinoka' and three selfed generations from 'Johong', 'Sachinoka' and 'Elan' were treated for 9 weeks with a low temperature of 5 degrees C and short daylength [photoperiod] of 8 hours during the summer. The flower bud formation rate of the progeny selfed from an ever-bearing variety, 'Elan' was 100%, whereas that of the progeny crossed from 'Johong' x 'Sachinoka' and that of the progeny selfed from 'Johong' and 'Sachinoka' showed 58.7, 22.6 and 54.4%, respectively. As a result, it proved that low temperature and short photoperiod is essential for flower induction but high temperature and long day condition is also necessary for flower development in strawberry. Crown diameter of seedling to react on low temperature and short day treatments must to be at least 9-10 mm, and it need about 80 days from sowing..