福岡県農業総合試験場研究報告22(2003) pp 43 - 47
水銀灯による終夜照明が大豆の生育，収量，および品質に及ぼす影響
福島裕助・内川修・塚﨑守啓
（農産研究所）
水銀灯による終夜照明が大豆の生育，収量および品質に及ぼす影響を明らかにした。照度0.5～44lxの範囲では， 開花遅延は開花結実習性がⅣｃの‘フクユタカ’がⅢｃの‘サチユタカ’より大きく，遅延日数は，‘フクユタカ’が1～63日，‘サチユタカ’ が1～11日であった。成熟遅延日数は，‘サチユタカ’が2～51日であったが，‘フクユタカ’は11lx以上の照度では試験を終了した12月25日までに 成熟しなかった。また，‘フクユタカ’は5lx以上では不稔莢が増加し，整粒数や百粒重の減少により減収したが，‘サチユタカ’は減収しなかった。 さらに，‘フクユタカ’は11lx以上で未熟粒の発生が多くなり外観品質が劣った。
‘フクユタカ’で，出芽直後から開花期後14日までの期間に7日間ごとに照明処理を行った場合，開花への影響が最も大きかったのは処理開始日が開花前27日の区で，開花期が6日遅れた。また，成熟遅延は開花前までの処理ではいずれも2～3日で，開花後の処理では1～2日であった。照度50lxでは，開花14日以前の処理で，稔実莢数の減少がみられ，5～12%減収した。照度15lxでは処理開始日が開花前27日の区で稔実莢数がやや減少したものの，減収は2%程度であった。
[キ－ワ－ド：大豆，減収，開花，水銀灯，終夜照明]
Influence of the All-night Lighting with Mercury-vapor Lamps on the Growth, Yield and Apparent Quality of Soybean. FUKUSHIMA Yusuke, Osamu UCHIKAWA and Morihiro TSUKAZAKI (Fukuoka Agricultural Research Center, Chikushino, Fukuoka 818-8549, Japan) Bull. Fukuoka Agric. Res. Cent., 22: 43 - 47 (2003)
Influence the all-night lighting with mercury-vapor lamps on the growth, yield and apparent quality of soybean was clarified. In the range of illuminance from 0.5 to 44 lx, the delay in flowering was greater on'Fukuyutaka'than on'Sachiyutaka', with the maximum number of days delayed in flowering 63 days and 11 days respectively. The delay in maturing in 'Sachiyutaka' was 2-51 days in the range of tested illuminance, although 'Fukuyutaka' failed to mature under the condition of more than 11 lx by 25th of December, when the experiment was terminated. Under the condition of over 5 lx, the ratio of sterile flower rose and the yield fell because of a decrease in the number of whole grain and a hundred grain weight in 'Fukuyutaka', although the yield of 'Sachiyutaka' did not decrease up to 44 lx. Apparent quality of grain was inferior at over 11 lx in 'Fukuyutaka'. The relative effect of all-night lighting treatment was measured at seven-days intervals beginning with the period of emergence to 14 days after flowering time. 'Fukuyutaka' was most sensitive to lighting in the period 27-21 days prior to flowering. In this period, the effect of lighting was a delay in flowering by six days. The number of days delayed in maturing was 2 to 3 days when the treatment was given prior to flowering and 1 to 2 days when the treatment was given after flowering. At under 50 lx of illuminance, yield decreased by 5-12% in the treatment of more than 14 days prior to flowering, although under 15 lx, yield decreased by only 2% in the treatment of 27-21 days prior to flowering.
[Key words: all-night lighting, flowering, mercury-vapor lamp, soybean, yield decrease]