Some Biological Characteristics of Tuber Formation in Eleocharis kuroguwai

올방개 괴경(塊莖) 형성(形成)에 관(關)한 생물학적(生物學的) 특성(特性)

Some biological characteristics with respect to tuber formation of Eleocharis kuroguwai Ohwi were investigated. Tuber formation was initiated at the descending time of daily maximum and minimum temperatures, accelerated under the minimum temperature lower than $20^{\circ}C$, and terminated at about $10^{\circ}C$. Tubers produced at the early season were located at deeper soil layers. Large tubers were found at deeper soil depths and required the longer period for sprouting as compared with small tubers. Percent emergence decreased as the emergence depth increased, while percent old-tuber produced during previous years was greater at the deeper depths.

올방개 괴경(塊莖) 형성(形成) 시기(時期)와 관련(關聯)된 괴경(塊莖)의 토중분포(土中分布)와 생태생리적(生態生理的) 특성(特性) 차이(差異)를 조사(調査)하였다. 1. 괴경(塊莖)의 형성(形成) 시기(時期)는 일중(日中) 최저온도(最低溫度)와 최고온도(最高溫度)가 하강(下降)되는 시기(時期)에 시작(始作)되며, 최저온도(最低溫度) $20^{\circ}C$ 이하(以下)가 될때 촉진(促進)되고, $10^{\circ}C$ 이하(以下) 부근에서 완성(完成)되었다. 2. 괴경(塊莖)의 토중(土中) 분포(分布)는 초기(早期)에 형성(形成)된 괴경(塊莖)일수록 심토층(深土層)에 분포(分布)하였다. 3. 깊은 토심(土深)에서 형성(形成)된 괴경(塊莖)이 괴경당(塊莖當) 생체중(生體重)이 크고, 맹아일수(萌芽日數)가 길었다. 4. 출아율(出芽率)은 이식(移植) 토심(土深)이 깊을수록 감소(減少)한 반면(反面), 구괴경(舊塊莖)의 잔존비율(殘存比率)은 증가(增加)되었다.