강원도(江原道) 지방(地方)에서 일반(一般) 관행법(慣行法)으로 재배(栽培)할 때 5월(月)제(第)1본엽(本葉) 출현후(出現後)부터 5월(月) 하순(下旬) 제(第)3본엽(本葉) 출현시(出現始)까지 경단조직(莖端助織)의 화아분화(花芽分化) 상태(狀態)를 관찰(觀察)한 바 참당귀의 화아분화(花芽分化)는 제(第)2본엽(本葉)이 출현한 5월(月) 중순경(中旬頃)으로 관찰되었으나 묘소질의 차이에 의한 개체별 분화기변리(分化期變異)가 심(甚)하였다. 따라서 재배관리상(栽培管理上) 추대(抽臺)를 억제(抑制) 또는 감소(減少)시킬 목적(目的)으로 억제(抑制) 물질(物質) 처리(處理), 일장(日長)이나 광도조절(光度調節) 등의 인위적(人爲的) 조치(措置)는 이 시기를 고려함이 바람직 할 것으로 사료(思料)된다.

The most important subject in cultivation of A. gigas NAKAI would be how to decrease the bolting rate. Belcause the decrease and poor of the yields and quality is imevitable in such field where the bolting rate is high. This study was carried out to investigate the time of flower-bud differentiation as a part of improvements of cultivation method. Shoot apex was fixed in Farmer's solution(ETOH 3:Acetic acid 1), thin paraffin ribbon was made, and the tissue was stained by Safranin solution. Differentiation time of flower-bud in A. gigas differed greatly from individuals by the seedling size, generally begun from middle of May to late of June, it was time that two leaves spread. In this results, Photoperiocid types of A. gigas NAKAI were regarded as LI type or LS type of dull-photosensitivity.

• 유창연 | Yoo, Chang-Youn
• 안상득 | Ahn, Sang-Deuk