EFFECT OF LIGHT QUALITY FOR SUPPLEMENTAL LIGHTING DURING RUNNER-COOLING TREATMENT ON FLOWERING OF STRAWBERRY IN FORCING CULTURE
Cooling the runner plants of strawberries to around 15°C in dark conditions is an artificial treatment used to induce flowering. However, the instability of flower bud initiation and the exhaustion of plants during treatment can be a problem. The aim of this study was to investigate effects of supplemental lighting quality during runner-cooling treatment on flower bud initiation and growth in strawberries. Runner plants of Sachinoka grown for 30 days under natural daylight were exposed to blue, green, red, or white light supplied by fluorescent lamps or light emitting diodes (LEDs) under a 14 h daily light period for 30 or 40 days at 15 or 17°C in growth cabinets. We observed the date of terminal flower bud emergence, and showed that blue light promoted flower bud emergence most effectively. In addition, we found that the petiole developed uselessly under blue LEDs alone, but plants showed normal morphogenesis under a mixture of blue (450 nm) and red (660 nm) LEDs. These results show that red light is necessary for normal morphogenesis, although blue light is important for the promotion of flower bud differentiation.
Yamazaki, K., Kumakura, H. and Hamamoto, H. (2011). EFFECT OF LIGHT QUALITY FOR SUPPLEMENTAL LIGHTING DURING RUNNER-COOLING TREATMENT ON FLOWERING OF STRAWBERRY IN FORCING CULTURE . Acta Hortic. 907, 291-294
blue light, flower bud emergence, fluorescent lamp, light emitting diode, light quality, strawberry