Chan Soo Kim

Comparison of genetic diversity in the two arctic–alpine plants Diapensia lapponica var. obovata (Diapensiaceae) and Empetrum nigrum var. japonicum (Empetraceae) between Sakhalin in Russian Far East and Jeju Island in Korea, the southernmost edge of their distribution range

We compared allozyme variation in the two arctic–alpine plants Diapensia lapponica var. obovata and Empetrum nigrum var. japonicum between Sakhalin Island in Russian Far East, within their range core, and the Korean island of Jeju, their world’s southernmost distribution. For D. lapponica var. obovata, Sakhalin populations harbored moderate levels of within-population genetic variation and low among-population divergence, whereas extremely low levels of within-population genetic diversity and high among-population differentiation were found in Jeju Island populations. In contrast, we found moderate levels of within-population variation and low among-population differentiation in E. nigrum var. japonicum in both northern populations (those of Sakhalin and an additional population from northern Japan) and Jeju Island populations. Under a similar scenario of immigration history of arctic–alpine plants on Jeju Island during the glacial periods of the Pleistocene and local persistence through glacial/interglacial cycles, the contrasting genetic structure between D. lapponica var. obovata and E. nigrum var. japonicum is mainly attributable to their different life-history, ecological, and demographic traits: (1) hermaphroditic versus monoecious, dioecious or polygamous, (2) seeds with no adaptations for long-distance dispersal versus berry-like drupes dispersed by animals and birds, and (3) a very small patch near the peak of Mt. Halla with a few hundred individuals versus a relatively continuous distribution around the peak of Mt. Halla with numerous individuals. From a conservation perspective, in situ and ex situ conservation measures should be strengthened for D. lapponica var. obovata on Jeju Island given their extreme rarity there.

Unrecorded species from Korean flora: Maesa japonica (Thunb.) Moritzi & Zoll. [Maesaceae] and Cardamine tanakae Franch. & Sav. [Brassicaceae]

제주도에서 한국 미기록과인 빌레나무과 (Maesaceae)의 빌레나무 (Maesa japonica)와 십자화과의 꼬마냉이 (Cardamine tanakae)가 채집되었다. 빌레나무과는 Maesa, 1속으로 구성된 과로서 소화경에 한 쌍의 소포엽이 있으며, 가웅예가 없고, 준자방하위이며, 다수의 종자를 갖는 폐과인 점 등으로 자금우과와 앵초과 식물과 구별된다. 빌레나무는 엽신, 화관 및 소포엽의 형태, 엽연부의 거치의 유무, 화통과 화관열편의 길이의 비율, 과실 표면의 특성 및 색깔에 의해 각각 중국, 대만 및 일본에 분포하는 M. salicifolia와 M. montana var. formosana와 뚜렷하게 구별되었다. 꼬마냉이는 경생엽의 소엽 수 및 정소엽의 크기, 한 화서에 붙는 꽃의 수, 자방 및 열매의 백색 연모의 유무의 특징에 의해 국내 고유종인 벌깨냉이 (C. glechomifolia)와 명백히 구분되었다.