培養液非更新水耕キュウリの接ぎ木による収穫期の延長

培養液非交換による水耕キュウリ'聖護院青長節成'の生育後半の収量低下が接ぎ木によって軽減できるかどうかを秋, 春および夏作で検討した.1. 栄養生長に関して, 3作とも自根区, '聖護院青長節成'台木区, '北進'台木区および'青大'台木区で大きな差は認められなかった.従って, 栄養生長に関しては台木の影響はほとんどないと考えられた.2. 総収穫果実数は'北進'および'青大'を台木にした場合夏作でのみやや増加した.週毎の収穫果実数では, '北進'および'青大'台木で収穫期後半の収穫果実数に低下傾向がみられず, 収穫期間が延長した.以上より, '北進'および'青大'を接ぎ木することにより培養液を栽培途中で廃棄せずに栽培することが可能となり, 水耕キュウリの収量低下を防ぐ方法が示唆された.

The effect of rootstocks in non-renewal solution culture of cucumber (Cucumis sativus L. cv. Shogoin-aonaga-fushinari), on sustaining yield in the late harvest period for autumn, spring, and summer crops was investigated. 1. Vegetative growth of 'Shogoin-aonaga-fushinari' plants at the end of the experiment was only slightly affected for the 3 seasons whether they were ungrafted or grafted on seedings of 'Shogoin-aonaga-fushinari', 'Hokushin' or 'Aodai'. There is no evidence that rootstocks influence vegetative growth. 2. The number of harvested fruit of 'Shogoin-aonaga-fushinari' in the summer crop was increased by grafting on the rootstock of 'Hokushin' or 'Aodai'. The weekly number of harvested fruit which decreased in the late harvest period on ungrafted plants was not observed on plants grafted on 'Hokushin' or 'Aodai' seedlings, thereby, extending the harvest season. Thus, the fruit yield in the closed nutrient flow system was sustained for a longer period by grafting 'Shogoin-aonaga-fushinari' on 'Hokushin' or 'Aodai' seedlings.