報告書番号

U03053

タイトル（和文）

夜間の短時間補光に対する数種野菜の成長反応

タイトル（英文）

Growth responses of several kinds of vegetables to brief exposures to supplemental lights during the night

概要 （図表や脚注は「報告書全文」に掲載しております）

夜間の青色や赤色の短時間補光は，低照度条件下のホウレンソウの成長不良改善に有効である。これらの補光を様々な葉菜類の生産に利用するため，最初に，青色光や赤色光の成長促進に対する引き金としての特徴をホウレンソウで調べた。赤色と遠赤色の光を交互に照射すると，赤色光による成長促進は，遠赤色光によって打ち消され，最後の光質が成長を決定した。一方，青色光については，夜の終了時に比べてその2時間ほど前に照射すると成長促進が大きいことがわかった。次に，シソ，エンサイ，サニーレタス，ダイコンを用いて，青色光，赤色光，遠赤色光の夜間の短時間照射が成長に及ぼす影響を調べた。ホウレンソウと同様ダイコンでは，遠赤色光による成長促進はみられなかったが，ほかの野菜では遠赤色光のみが成長を促進した。この結果は，遠赤色光に対する成長反応の異なる2タイプの植物が存在することを示し，様々な葉菜類の生産に対する短時間補光の効果的な利用に役立つと考えられる。

概要 （英文）

In our previous study it was confirmed that a brief exposure to supplemental blue or red light during the night was useful in improvement of insufficient growth of spinach under low level of photosynthetic active radiation during the daytime. To make use of the supplemental lighting in production of various leaf vegetables, characteristics of blue and red lights as a trigger to acceleration of growth were investigated in the case of spinach. When plants were irradiated with supplemental red and far-red lights one after another, acceleration of growth by red light was cancelled by far-red light, the most recent light quality determining the growth. On the other hand, as to supplemental blue light, it became clear that the growth was accelerated when plants were irradiated with the light two hours before the end of the night in comparison to just at the end of the night. Next, using Japanese basil, water convolvulus, leaf lettuce and Japanese radish, the influence of brief exposures to blue, red and far-red lights during the night on growth was investigated. In the case of Japanese radish, as in spinach, acceleration of growth did not occur by exposure to far-red light, while growth of other vegetables was accelerated by exposure to far-red light only. This result shows that there are two different types of plants according to the growth response to far-red light, and it is useful in making effective use of brief supplemental lighting in the production of various leaf vegetables.

報告者

キーワード