チューリップ「花飛ばし」高温処理に関する研究(第1報)

処理時期,日数が発育,開花並びに球根収量に及ぼす影響について

抄録

The high temperature treatment of tulip bulbs is known to be an effective method for making the bulbs blind and inducing rapid multiplication of new bulbs. This study was carried out to ascertain the most effective date and length of the treatment on the two varieties, Farncombe Sanders and Prince of Wales.
In 1952, the 35°C treatments were started from Aug. 8, Sept. 8, or Oct. 8, for 13, 15 and 17 days. It was found that 20 days treatment started from Aug. 8 had almost no effect, but the treat-ment started from Sept. 8 induced about 50 percent blind, and the treatment started from Oct. 8 did 100 percent blind.
In the 1953 experiment, 20 days treatment start-ed from Sept. 15, 13_??_15 days treatments started from Sept. 30, and 10 days treatment started from Oct. 15, respectively, had almost same effect on the bulbs and induced 100 percent blind.
The observation revealed that the apical bud in the bulbs were injured by the high temperature treatment, and the axillary buds were promoted to growth, thus the number and the weight of new bulbs were increased. But when too long treat-ments were applied, new growth was impaired, and the yields of the new bulbs were decreased. It seemed that the growth of the axillary buds was promoted by the loss of the apical dominancy in the bulbs with the high temperature treat-ments.
The effectiveness of the treatments was varied depending on the date the bulbs were treated or on the varieties used. This may due to the degree of growth or dormancy of the bulbs when they were treated. From the experiments, it was cle-ared that the most successful treatment was about 13 days treatment of 35°C degree started from early October, and when the treatment was start-ed earlier, the bulds should be treated a little longer.