蔬菜・花卉の生長・生理に及ぼすジベレリンの影響(第 1 報)

ジベレリンは作物の種類により, その濃度, 撒布時期, 撒布回数等の影響が非常に異るものであるから, 個々の作物の最適条件を見出して応用しなければならない。本実験は園芸作物を材料として, その結果を報告するものである。1. マリー・ゴールドの生育および開花現象に対しては1.25∿10.0ppm濃度で影響を及ぼす。特に2.5ppm水溶液1回の葉面撒布の場合, 生育が最もよく, 又開花も1週間早くなる傾向をしめした。2. 花椰菜の花蕾叢の出現に対しては, 1.25∿2.5ppm水溶液を定植後3∿4回撒布することにより効果を認められる。3. 九条葱の生育に対してはジベレリンの1.25∿10ppm水溶液3回撒布では効果は殆んど認められない。10ppm水溶液3回撒布により分蘖数はやゝ増加し, 開花を遅らせる傾向を認めた。4. セルリーの生育に及ボすジベレリンの効果は, 10ppm水溶液3回撒布により, 葉長に於ては10糎以上増加し, 葉数に於ては影響はみられなかつた。重量に於ては170瓦の増加をみた。5. チユーリツプの生育及び開花現象に対しては, 100ppm水溶液8回撒布により草丈に於て6糎, 花梗長に於て8糎の増加を示し, 開花も10日早くなる傾向を示した。6. チユーリツプ球根を0.625∿20ppm濃度に24時間浸漬した場合, 発芽, 草丈および花梗長には影響が認められなかつた。開花状態は葉面撒布処理した場合と逆に低濃度で処理した程, 開花始めは早い傾向をしめした。7. ジベレリン水溶液にチユーリツプ球根を24時間浸漬することにより, dropperの発現率をたかめ, 待に1.25∿5.0ppm水溶液浸漬に於て顯著である。Gibberellin must be applied under the best possible condition, because its density and its time and frequency of spraying, etc. make very different effects according to the kind of plant to which it is applied. This is a report of the results of the experiments made by horticultural crops. (1) In the case of the growth and blooming of Marry Gold, it is effective in the density of 1.25∿10.00ppm Especially in the case of onepantspray of 2.5ppm solution, the best growth was obtained and blooming seemed to come one week earlier. (2) In the case of the appearance of the head of the Cauliflower, three or four sprays of 1.25∿2.5ppm solution after planting proved effective. (3) In the case of the growth of Onion (Kujyo), three sprays of 1.25∿10ppm solution of Gibberellin proved almost uneffective. By three sprays of 10ppm solution there was observed the tendency that the number of suckers increased a little and blooming was delayed. (4) As regards the effect of gibberellin on the growth of Cerley, three sprays of 10ppm solution incresed the length of the leaf more than 10cm. and gave no effect on the number of leaves; the weight of individual stab increased 170gr. (5) In the case of the growth and blooming of the Tulip, after eight sprays of 100ppm solution there was observed the tendency that the length of the leaf increased 6cm., the flower stalk grew 8cm. and blooming came 10 days earlier. (6) When the bulbs of the Tulip were soaked in solution of 0.625∿20.0ppm density for 24 hours, there was observed no effect on their germination, lengths of leaves and flower stalks. Inverse to the case of the process of plants sprayed, there was observed the tendency that the lower the density was, the earlier came blooming. (7) By soaking the bulbs of Tulip in gibberellin solution for 24 hours, the percentage of the appearance of dropper was increased. This was prominent especially in the case of soaking them in 1.25∿5.00ppm solution