Iris laevigata, which belongs to the Iridaceae, is now designated as an “endangered” (EN) grade by Korea Forest Service because it does not have many natural sites known for its reckless development and damage to its natural habitats. This study was carried out to establish the propagation protocol from seed to restore the native habitat of the I. laevigata and to utilize it for ornamental purposes. Basically, the appearance and internal structure of seeds were observed and imbibition experiments were conducted. Germination rate was measured by cold stratification experiment, after warm followed by cold stratification experiment, and GA3 treatment experiment. The seeds had underdeveloped embryos, which had grown to about 25% of those of fully matured seed before germination. In the controlled laboratory experiment, after cold stratification at 5°C for 0, 4, 8, or 12 weeks, the seeds germinated to 0, 11.7, 43.4, or 51.7%, respectively, after 4 weeks of incubation at 25°C. After warm stratification (25°C, 8 weeks) followed by cold stratification for 0, 4, 8, or 12 weeks, the seeds germinated to 0, 51.7, 85.0, or 88.3%, respectively, after 4 weeks of incubation at 25°C. GA3 treatment did not overcome the dormancy. Our study determined the dormancy type of I. laevigata seed. Imbibition experiments showed that there was no physical dormancy, and it was also found that there was an underdeveloped embryo when it was observed that the embryo was growing according to the period of incubation. A nd t he e m bryo grew a t relatively w arm temperatures. It is concluded that the seeds of I. laevigata have morphophysiological dormancy (deep simple MPD). This is the first report to determine the dormancy type in seeds of this valuable ornamental plant.

본 연구는 특산식물 노랑붓꽃 자생지의 식물상 및 식생조사를 통하여 노랑붓꽃자생지의 보전 및 관리를 위한 기초자료를 제공하기 위하여 수행하였다. 노랑붓꽃 자생지 내에서 출현한 관속식물은 63과 97속 121종 3아종 11변종 3품종으로 총 138분류군으로 확인되었다. 특산식물은 노랑붓꽃을 포함한 청괴불나무와 병꽃나무 등 3분류군이 확인되었다. IUCN 평가기준에 따른 희귀식물은 멸종위기(CR)종 노랑붓꽃(Iris koreana)과 약관심(LC)종 말나리(Lilium distichum)가 조사되었다. 식물구계학적 특정식물종은 Ⅴ등급 1분류군, Ⅳ등급 2분류군, Ⅲ등급 2분류군, Ⅱ등급 3분류군 및 Ⅰ등급 11분류군 등 19분류군이 발견되었다. 생활형조성은 교목(21.0%), 저목식물(21.0%), 지중식물(18.8%), 아교목(16.7%) 등이 높게 나타났다. 식생구조를 중요치와 종다양지수로 분석한 결과, 관목식물 중에서는 윤노리나무(Pourthiaeavillosa)의 중요치가 14.5%로 가장 높게 나타났으며, 초본식물 중에서는 애기나리가 10.2%로 가장 높은값을 나타내었다. 노랑붓꽃 자생지의 평균 종다양성지수는 1.4로 비교적 낮은 것으로 나타났다. 직경급빈도분포를 분석한 결과, 대부분의 자생지에서 직경 10cm 이상의 성숙목 계급에서는 소나무(Pinusdensiflora), 곰솔(Pinus thunbergii), 갈참나무(Quercus aliena) 및 굴피나무(Platycarya strobilacea)의 출현빈도가 높게 나타났고, 직경 10cm 이하의 어린 식물계급에서는 굴피나무, 때죽나무(Styraxjaponicus), 갈참나무의 출현빈도가 높게 나타났다. 전반적으로 조사지역의 식생은 양호하나 최근 들어 인위적인 간섭 및 자연재해로 인하여 훼손이 증가되고 있어 장기적인 모니터링을 통한 식생변화와 동태 파악이 이루어져야 할 것으로 판단된다.

The sustainability of Iris koreana, a rare and endemic plant designated by the Korea Forest Service, is threatened due to artificial factors such as habitats loss and climate change etc. and internal factors such as changes in biological properties of the habitats etc. but conservation biology research has not been performed in South Korea. The objective of this study is to establish the species conservation strategies by analyzing the characteristics of their habitats, including: 1) Population characteristics, and 2) habitat analysis of the vegetation and abiotic environments. From April to May, 2015, population characteristics [density (stems m-2), flowering rate (%) and leaf area size (cm2)] in I. koreana habitats such as Buan1~6 (BA1~6), Jangseong1~2 (JS1~2) and vegetation characteristics (phytosociological research and ordination analysis), and abiotic environments [soil temperature (℃), soil humidity (%), transmitted light (mol·m-2·d-1) and canopy openness (%)] were measured. I. koreana was mainly distributed at elevation 50 to 150 m and 2 to 11° slope. Slope direction was shown as 90 to 193°. The average degree of canopy openness was 11.9%. It showed the highest at BA2 (17.5) and the lowest at JS1 (7.7). The average degree of transmitted light was 6.3 mol·m-2·d-1. It showed the highest at BA2 (10.1) and the lowest at JS1 (3.6). Population density showed average 25.8 (stems m-2). It showed the highest at JS2 (19.7) and the lowest at JS1 (9.3). flowering stems showed average 16.9 (stems). It showed the highest at BA3 (35) and the lowest at BA5 (4). Leaf area size was average 94.1 cm2.

댐호, 저수지, 하천 등 수위변동이 있는 비탈면의 녹화용 식물재료를 선발하기 위하여 내습성을 지닌 4종류의 Iris속 식물을 대상으로 완전침수와 부분침수 조건에서 침수기간별로 생존 및 생장특성 등을 비교 조사하였다. 생존율과 생장상태를 기준으로 한 내침수성은 노랑꽃창포 > 꽃창포 > 부채붓꽃 > 붓꽃의 순서로 나타났다. 특히, 노랑꽃창포는 120일까지의 완전침수 조건에서 생장장해를 입기는 하지만 생존율이 높았고 지속적으로 양호한 생장을 하였으며, 부분침수조건에서는 침수기간이 증가할수록 생장이 양호한 것으로 보아 내침수성이 강한 것으로 확인되었다. 붓꽃, 부채붓꽃, 꽃창포는 완전침수조건에서 다소 많은 생장장해를 입으며 90일 이후에 고사되었으나, 내침수성이 비교적 강한 것을 확인할 수 있었으며, 수위변동에 따라 생장회복이 가능할 것으로 판단된다. 본 시험을 통해 댐호의 저수 비탈면과 각종 저수구역 내의 식생공사용으로서 노랑꽃창포, 꽃창포, 부채붓꽃, 붓꽃의 이용가능성을 확인하였다.

This study was carried out to provide the basic data for an identifying system for Iris species distributed in Korean market from complete analysing of genetic relationship between three native Iris species and one cultivar bred from the native Iris plant. RAPD analysis of genetic relationship among 4 Irises was possible. According to the RAPD analysis, they were divided into two groups. Among 4 Irises used in this study, Iris laevigata 'Veriegata', Iris laevigata and Iris setosa were classified into the same group since they had many similarities even though the habitat of Iris laevigata in Korean peninsular is restricted mainly in the south and Iris setosa is naturally inhabited in the northern part of Kangwondo. The value for the dissimilarity index of Iris laevigata and Iris laevigata ‘Veriegata’ was 6.757. The value for the dissimilarity index of Iris laevigata and Iris dichotoma was 95.000, so that they were genetically the farthest among them since the genetic relationship between two species are separated far if the value of the dissimilarity index is close to 100.

Karyotypes were established in the eight Korean native species of the genus Iris. Chromosome numbers were 2n=50 in I. koreana and 2n=42 in I. uniflora var. carinata and their karyotype formulas were K = 2n = 50 = 14m + 28sm + 8st and K = 2n = 42 = 16m + 26sm, respectively. I. dichotoma and I. pseudoacorus were diploids of 2n=34. However, they showed different karyotype formulas: K = 2n = 34 = 26m + 6sm + 2st in I. dichotoma and K = 2n = 34 = 8m + 24sm + 2st in I. pseudoacorus. I. setosa, and I. pallasii var. chinensis carried the same chromosome numbers of 2n=40, but they showed different patterns of karyotype formula: K = 2n = 40 = 22m + 14sm + 4st in I. setosa and K = 2n = 40 = 26m + 12sm + 2st in I. pallasii var. chinensis. I. sanguinea was a diploid of 2n=28 and the karyotype formula was K = 2n = 28 = 14m + 14sm. I. ensata var. spontanea was a diploid of 2n=24 and the karyotype formula was K = 2n = 24 = 10m + 14sm. Each species showed characteristic chromosome composition with a pair of satellite chromosome except I. koreana with three pairs of satellite chromosomes. The chromosomes of I. dichotoma and I. uniflora were comparatively short, while the chromosomes of I. ensata were remarkably bigger than those of other species. These cytological data will give a useful information for the identification and breeding program of the Iris plants.