Abstract
The effect of far-red light (EOD-FR) and heating (EOD-heating) treatment at the end of the day (EOD) on growth for spring shipping of Eustoma grandiflorum (Raf.) Shinn was investigated. Plants treated with both EOD-FR and EOD-heating after transplanting on October 29 showed early flower budding associated with a longer main stem and a higher node number compared with untreated plants. SPAD values of the upper leaves and the nitrogen content of leaves in these plants on May 13 were higher than in other treated plants. In contrast, the nitrogen content of roots in both treated plants was lower than in other plants. On measuring the translocation of photosynthate in the early stages, 13C atom% excess in the stems and leaves of plants under 18°C・FR treatment and in roots on EOD-heating was significantly higher than in plants under 18°C treatment. From these results, it was clarified that both treatments of EOD-FR and EOD-heating at 13°C can advance the growth of plants and stems more than 18°C treatment and effect the activation of photosynthate allocation in early developmental stages to promote growth for spring shipping in regions with low leaves of sunshine during winter.
