Abstract
The Koran native economic and ornamental trees consisting 12 species of 4 gymnosperm families and 3 strains, 6 varieties and 18 species of 12 angiosperm families were irradiated by X-and ${\gamma}$-ray at three different dose rates; 1) acute, 2) semi-acute, and 3) chronic irradiation in order to know their radiosensitivities and the radition effects on mutation induction. Different materials such as seeds, cuttings, scions and plants of the above trees were used in this study, depended upon tree. Most of the materials irradiated showed a high radiosensitivity. The LD-50 of conifer trees ranged from 1.2kR to 13.2kR, averaging 5.4kR which was remarkably higher than field crops. On the other hand the LD-50 dose of hard wood trees ranged from 7.0kR to 18.5kR, averaging 12.7kR. All the tested trees were classified into several categories based upon the relative radiosensitivity of each species which was measured at the dose of LD-50. Variegation was most common among the induced mutants. The other mutations were albino, chlorophyll deficiency, deformed leaf and fruits. It was noticeable that giant-leaf bud-sport mutants were induced in Chinese chestnut (Castanea bungeana) and yellow leaf bud-sport ones appeared in oriental arborvitae (Thuja orientalis).
나자식물(裸子植物) 4과(科), 12종(種)과 피자식물(被子植物) 12과(科), 18종(種), 6품종(品種), 3계통(系統)의 한국산(韓國産) 경제수종(經濟樹種) 및 관상수종(觀賞樹種)의 종자(種子), 삽목(揷木), 접수(接穗) 및 생체(生體)에 X선(線) 또는 ${\gamma}$선(線)을 급조사(急照射), 반급조사(半急照射) 또는 완조사(緩照射)를 실시하여 수종별(樹種別) 방사선감수성(放射線感受性) 및 변이(變異)의 출현(出現)을 조사(調査)하였다. 공시수종(供試樹種)의 대부분(大部分)은 높은 방사선감수성(放射線感受性)을 보였으며 침엽수(針葉樹)는 LD-50이 1.2 kR~13.2 kR 범위(範圍)로 평균(平均) 5.4 kR의 심(甚)히 높은 감수성(感受性)을 보였고, 활엽수(濶葉樹)는 LD-50이 7.0 kR-18.5 kR범위(範圍)로 평균(平均) 12.7 kR이였으며 수종간(樹種間)의 비교방사선감수성(比較放射線感受性)을 LD-50을 기준으로 분류(分類)하였다(Table 2). 출현(出現)하는 변이중(變異中)에는 반문엽(斑紋葉)이 가장 많았고, 백자(白子), 엽록소결핍(葉綠素缺乏), 기형엽(奇形葉), 기형과(奇形果)등의 출현(出現) 및 약밤나무의 대형엽(大形葉) 아조변이(芽條變異)와 측백나무의 황색엽(黃色葉) 아조변이(芽條變異)가 유기(誘起)되었다.