サトイモ球茎の発芽に及ぼす掘り上げ時期と低温処理の影響(栽培管理・作型)  [in Japanese] Effect of Harvesting Time and Low-Temperature Treatment on Germination of Corm in Taro : Colocasia esculenta Schott(Crop Production & Cropping Type)  [in Japanese]

本実験は,サトイモ(Colocasia esculenta Schott)の球茎の休眠の品種間差異および低温処理による休眠打破の効果を調べる目的で行った.'えぐいも','早生蓮葉','赤芽','筍芋'およびマレーシア産の系統(マレーシア1)を供試し,9月21日と11月23日に掘り上げた球茎について,掘り上げ直後に25℃で発芽試験を行った.その結果,'早生蓮葉''えぐいも'では,9月21日掘り上げ球茎では発芽が非常に遅く,11月23日掘り上げ球茎はすぐに発芽した.'筍芋'およびマレーシア1は,掘り上げ時期に関係なくすぐに発芽した.'赤芽'は,9月21日掘り上げ球茎ではやや発芽が遅かった.'えぐいも'を供試し,10月3日に掘り上げた球茎を,3℃または10℃で0〜60日間および25℃で60日間処理後,発芽試験を行った.その結果,3℃で15日間または10℃で30日間以上処理すると発芽が著しく促進された.低温処理の効果は,'八頭','石川早生丸','大野芋'でも同様にみられた.本実験の結果,サトイモにおいては,9〜10月初めに掘り上げた球茎で休眠がみられる品種とみられない品種があり,低温処理により休眠が打破されることが示された.

Studies were carried out to elucidate the effect of harvesting time and low-temperature treatment on germination of corm in taro (Colocasia esculenta Schott). Corms of cvs. Eguimo, Wase-Hasuba, Akame, Takenokoimo and Malaysia No. 1 were harvested on 21 September and 23 November. They were planted in a growth chamber at 25℃ just after harvesting. In cvs. Eguimo and Wase-Hasuba, the germination rate of corms harvested on 21 September was much lower than that of those harvested on 23 November. In cv. Akame, the germination rate of corms harvested on 21 September was slightly lower than that of those harvested on 23 November. In cvs. Takenokoimo and Malaysia No. 1, corms germinated rapidly irrespective of harvesting time. Corms of cv. Eguimo were harvested on 3 October and stored at 3, 10 or 25℃ for 0-60 days. The germination rate was low in corms planted just after harvesting or after storage at 25℃ for 60 days. Low-temperature treatment at 3℃ for 15 days or at 10℃ for more than 30 days strongly promoted germination. Low-temperature treatment also promoted germination of corms in cvs. Yatsugashira, Ohnoimo and Ishikawa-wase. Based on these findings, it was deduced that taro corm remains dormant from late September to early October, that the depth of dormancy varies with variety, and that dormancy is broken with low-temperature treatment at 3℃ for 15 days or at 10℃ for 30 days.