著者

Kenji Suetsugu Shun K. Hirota Koji Yonekura Atsushi Abe Yoshihisa Suyama Tian-Chuan Hsu

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.74, no.2, pp.121-129, 2023-07-31 (Released:2023-09-08)

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The present study documents the first record of Thrixspermum annamense (Orchidaceae) from Iriomote Island, Ryukyu Islands, Japan, expanding its known distribution beyond Vietnam, Thailand, Taiwan, China, and Malaysia. While the morphologically similar taxon T. fantasticum is present on the island, it can be distinguished from T. fantasticum by its somewhat narrower and more rigid leaves, slightly narrower sepals, densely hairy midlobe of the lip, and the absence of two horn-like appendages at the base of the midlobe. A detailed morphological analysis also revealed that the plants discovered on Iriomote Island closely resemble T. annamense from Taiwan but show consistent morphological and molecular distinctions from T. annamense from Vietnam, the type locality. Despite those differences, the high similarity in gross morphology and most lip structures of the plants from Japan, Taiwan, and Vietnam indicates that they all belong to T. annamense at the species level. Consequently, considering the genetic and morphological differences, we propose resurrecting the name T. devolianum, originally described from Taiwan, and reclassifying it as a variety of T. annamense (T. annamense var. devolianum). A neotype for T. devolianum is also designated.

著者

Norikazu Okabe Tetsukazu Yahara Shuichiro Tagane Chika Mitsuyuki Ayumi Matsuo Takanori Sasaki Etsuko Moritsuka Kengo Fuse Usun Shimizu-Kaya Julia Anak Sang Runi Sylvester Pungga Yoshihisa Suyama

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.72, no.1, pp.43-59, 2021-02-28 (Released:2021-03-21)

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A new species, Actinodaphne lambirensis Tagane, Yahara & N. Okabe (Lauraceae) from Lambir Hills National Park, Miri District, Sarawak, Malaysia, is described and illustrated. It is characterized by glabrous twigs and leaves, small lamina (4.3–9.2 × 1.7–2.8 cm), and long fruiting peduncles. Because only fruiting specimens were available, the position of A. lambirensis was determined by the phylogenetic trees based on 22 species of Actinodaphne, including the type species of the genus, A. pruinosa Nees, and 11 species of Neolitsea from Southeast Asia using multiplexed inter-simple sequence repeats genotyping by sequencing (MIG-seq). Additionally, a phylogenetic tree was constructed using internal transcribed spacer (ITS) sequences for 36 species of Actinodaphne and 40 species of Neolitsea that include our MIGseq samples and additional species for which ITS sequences were determined in previous studies. Both the MIG-seq tree and ITS tree supported A. lambirensis as belonging with Actinodaphne.

著者

Naoyuki Nakahama Azusa Ito Shingo Kaneko Yu Matsuki Yoshihisa Suyama Azusa Hayano Miho Murayama Yuji Isagi

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

pp.17-00021, (Released:2018-01-17)

被引用文献数

3

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Microsatellite markers were developed for the endangered orchid Calanthe izu-insularis (Orchidaceae). This species is unique to the Izu Islands in Japan. Unfortunately, its population size has decreased because of excessive collection for horticultural purposes. In addition, although natural hybridization between C. izu-insularis and C. discolor var. discolor has been reported, morphological differences between C. izu-insularis and the hybridized individuals remain unclear. Using next-generation sequencing, 11 polymorphic microsatellite markers were developed. All developed markers could amplify C. aristulifera and nine markers could amplify C. d. var. discolor, two other orchid species that are also endangered in Japan. The number of alleles and expected heterozygosity at each locus were 1–6 (mean, 2.35) and 0.00–0.79 (mean, 0.30), respectively. These microsatellite markers will help conservation geneticists in their investigation of the proportion of pure C. izu-insularis individuals in the Izu Islands.

著者

沼野 直人 陶山 佳久 Naoto NUMANO Yoshihisa SUYAMA

出版者

東北大学大学院農学研究科附属複合生態フィールド教育研究センター

雑誌

複合生態フィールド教育研究センター報告 = Bulletin of Integrated Field Science Center

巻号頁・発行日

no.22, pp.31-37, 2006-12-01

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樹木個体群の遺伝的多様性と空間的遺伝構造は,種子散布と花粉散布を介した遺伝子流動範囲に大きく影響される。しかしながら,これまでに森林内の優占樹種を対象として行われてきた研究では,遺伝子流動範囲をカバーする面積を対象とすることはほとんどなかった。そこで本研究では,伐採によって分布の連続性が低下したブナ個体群を対象として,残存するブナ成木の遺伝的多様性と空間的遺伝構造を大面積調査によって明らかにした。これによって,1)遺伝子流動範囲における詳細な遺伝構造と,2)残存ブナ個体群における遺伝的多様性と遺伝構造の現状,3)伐採等による樹木個体群の小集団化が遺伝的多様性と遺伝構造に及ぼす影響を明らかにすることを目的とした。2005年及び2006年の早春,東北大学大学院農学研究科附属複合生態フィールド教育研究センター内の約500haの同一河川流域内に設定した調査地内をくまなく踏査し,胸高直径15cm以上の全てのブナ成木1571本から葉の採取を行った。それらについてSSR7遺伝子座の遺伝子型を決定し,遺伝的多様性と空間的遺伝構造について解析を行った。その結果,残存ブナ個体群においては,分集団間レベルでは遺伝的に有意な集団の分化は起きていないが,個体間レベルでは約90m未満の範囲に遺伝的に類似した個体が生育していることが明らかとなった。また,残存個体群において遺伝的多様性が低下している傾向は認められず,近親交配が過剰に起きている傾向も認められなかった。さらに,小集団化後に更新したと考えられる成木であっても,遺伝的多様性の低下や遺伝的な集団の分化の傾向は認められなかった。これらの結果は,ブナの遺伝子流動の特徴である近距離の旺盛な種子・花粉散布と,量的には少ないが種子生産に効果的に働く長距離花粉散布を反映したものであると考えられた。