オオナルコユリの根茎における休眠と休眠打破(発育制御)  [in Japanese] Rhizome Dormancy and Its Breaking in Polygonatum macranthum (Maxim.) Koidz(Growth Regulation)  [in Japanese]

1. オオナルコユリの戸外栽培株の根茎の休眠(内生休眠)は7月上旬以前には極めて深かったが, その後, 日数の経過とともに徐々に浅くなり, 11月下旬以後は約5〜8℃に低下した平均気温も休眠打破を促進して, 休眠の深さの減少が一層進み, 2月下旬〜3月下旬には休眠がほぼ覚醒した.2. 休眠がほぼ覚醒した根茎の萌芽に適した温度は25〜30℃であった.3. 戸外で育成された根茎に対する休眠打破のための低温処理は8月下旬以後が有効で, 十分な休眠打破効果を得るためには, 5℃で約90日間以上処理する必要があった.4. 根茎がつながった状態の多くの芽をもつ根茎群を植え付けた場合には, 約半数の芽しか萌芽しなかったが, 1つの芽のみをもつ根茎を植え付けた場合にはすべての芽が萌芽した.

The rhizomes of Polygonatum macranthum (Maxim.) Koidz. undergo a period of endodormancy after the formation of new rhizomes in summer. The decrease in the dormancy level with time and the chilling requirements for breaking dormancy are examined in this paper. The rhizome dormancy was deepest in early July or earlier, and after this the level of dormancy decreased gradually with time. After late November the decrease was more progressive, as a result of exposure to low outdoor temperatures. The rhizome dormancy was almost broken by late February to late March. The optimum temperature range, for sprouting of rhizomes almost released from dormancy, was 25 to 30℃. Chilling was effective in breaking the dormancy of rhizomes when the rhizomes were dug in late August or later. The rhizomes dug in late September required a 120-day period of chilling at 5℃ to break dormancy completely, whereas a 90-day period of chilling at 5℃ was enough to completely break the dormancy of those dug in late October. When connected rhizomes with many buds were planted, half the number of buds did not expand. However, all buds expanded when divided rhizomes with only one bud were planted.