著者

Shotaro Midorikawa Kohtaroh Shutoh Takashi Shiga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.71, no.1, pp.55-63, 2020-02-29 (Released:2020-03-17)

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Najas minor and N. oguraensis (Hydrocharitaceae) are annual submerged plants and are difficult to distinguish owing to their similarities. While the number of anther locules and the size of the leaf epidermal cells differ between the two species, the anther locules are often difficult to observe on herbarium specimens and the effectiveness of using the size of the leaf epidermal cells as a taxonomic key character is currently unknown. We examined the size of the leaf epidermal cells in living plants and in dried specimens to evaluate the effectiveness of this feature in species identification. We first identified the two species by observing the anther locule number and then compared the size of the leaf cells in fixed and dried specimens. To identify plant fragments, we examined differences in epidermal cell length and width depending on the position of the cells within the plant. The length and width significantly differed in both fixed and dried leaves between the species. In particular, the epidermal cells of N. oguraensis ( > 160 μm) were about twice as long as those of N. minor regardless of leaf position. We therefore concluded that cell size, especially length, is a valid method for identifying the species in both fresh and dried condition. This method is effective where precise identifications are necessary, such as in floristic surveys and environmental assessments.

著者

Kenji Ogaki Kenji Suetsugu Keiju Kishikawa Daisuke Kyogoku Kohtaroh Shutoh Yuji Isagi Shingo Kaneko

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.94, no.5, pp.225-229, 2019-10-01 (Released:2019-12-10)

参考文献数

27

被引用文献数

1 3

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Gastrodia is the most species-rich genus among mycoheterotrophic plants, and is thus an essential taxon to understand the mechanism of species diversification in mycoheterotrophs. In this study, we developed microsatellite markers with high transferability for four Gastrodia species to examine genetic differentiation and similarity among species, populations and individuals. The 12 microsatellite markers developed from a G. fontinalis library showed high transferability for the ramets that identified G. nipponica, G. kuroshimensis and G. takeshimensis. In addition to the high transferability of these markers, we observed low allele variation within a sampled population of each species and allele differences among the four species. The 12 markers described here will be useful for investigating the genetic differences among and within the Gastrodia species, which evolved by a limitation of gene flow.

著者

Yasuro Kadono Tomoyoshi Noda Kazumasa Tsubota Kohtaroh Shutoh Takashi Shiga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.70, no.2, pp.129-134, 2019-06-30 (Released:2019-07-10)

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An alien member of the Utricularia (Lentibulariaceae) discovered in Japan is currently assigned to U. inflata, a native of North America. However, some morphological traits differ between the plants in Japan and U. inflata, including the apex of the floral spur and filament of the stamens. The alien plants are completely sterile, while U. inflata is capable of seed production. DNA analysis revealed that the chloroplast DNA sequences of the alien also differ from those of U. inflata in four regions. We provisionally determine the alien plants to be U. cf. platensis, a South American species with which it shares many traits.

著者

Hiroyuki Nakagawa Hidetoshi Nagamasu Shuichi Nemoto Shizuka Fuse Atsushi Ebihara Kohtaroh Shutoh

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.73, no.2, pp.151-157, 2022-06-30 (Released:2022-07-24)

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Leymus komarovii (Roshev.) J. L. Yang & C. Yen (Triticeae, Poaceae) is a rare species in Japan, reported only twice from Hokkaido. In 2018, an additional specimen of L. komarovii was collected in Oketo-cho, Tokoro-gun, Hokkaido. Subsequent examination of specimens in Japanese herbaria revealed that its distribution range in Hokkaido was wider than previously known. Asperella longearistata (Hack.) Ohwi f. glabra Ko. Ito, described from Hokkaido, is reduced to synonym under L. komarovii and a lectotype for Hystrix sachalinensis Ohwi, another synonym of L. komarovii, is designated, superseding a previous lectotypification. A detailed description of L. komarovii based on Japanese materials and a key to the Japanese taxa of Leymus is provided.

著者

Kohtaroh Shutoh Mitsuru Usuba Hiroki Yamagishi Yushi Fujita Takashi Shiga

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.71, no.1, pp.33-44, 2020-02-29 (Released:2020-03-17)

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Potamogeton ×angustifolius (P. gramineus × P. lucens) was newly recorded in Japan from a pond in Tsugaru-shi, Aomori Prefecture. The hybrid nothospecies was identified based on morphological observations and measurements, molecular analyses using cloned nuclear adhA gene and chloroplast rpl20–rps12 intergenic spacer, and pollen viability. The putative hybrid had morphological traits intermediate between P. gramineus and P. lucens, nuclear haplotypes matching those of the two parental lineages, and lower pollen viability than P. lucens (not compared with P. gramineus). The maternal lineage of the hybrid was presumed to be P. gramineus, based on chloroplast sequences. The hybrid characteristically shows well-branched stems in the upper part of shoots, as in P. gramineus, and both clearly petiolate and sessile submerged leaves with distinctive netted venation. Similar plants were collected in the 1980s from a ditch near the pond, suggesting that the hybrid may have been present for more than 30 years in this area.

著者

Kohtaroh Shutoh Shingo Kaneko Takahide Kurosawa

出版者

The Japanese Society for Plant Systematics

雑誌

Acta Phytotaxonomica et Geobotanica (ISSN:13467565)

巻号頁・発行日

vol.68, no.3, pp.181-192, 2017 (Released:2017-11-24)

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Pyrola subaphylla (Pyroleae, Ericaceae), which generally produces reddish scapes and scale-like or extremely small leaves, has been treated as a variety or form of the closely related P. japonica, which generally has green scapes and fully developed leaves, owing to observations of individuals with intermediate morphology. Recently, these two taxa were shown to differ genetically, supporting recognition of P. subaphylla as a distinct species. We identified herbarium specimens as P. subaphylla when (1) at least three shoots were mounted on the same sheet, (2) leaf blades <3.0 cm in length were present on all mounted shoots, and (3) at least one flowering shoot either lacked ordinary leaves, which are distinguished from scale-like leaves with blade >1 cm long, or bore only a single ordinary leaf. A revised taxonomic treatment of the species is proposed. In Japan, P. subaphylla occurs in Hokkaidō, Honshū (Tōhoku and Chūbu district), and Shikoku, usually in coniferous forests at 0–1,500 m.

著者

Keiju Kishikawa Kenji Suetsugu Daisuke Kyogoku Kenji Ogaki Daisuke Iga Kohtaroh Shutoh Yuji Isagi Shingo Kaneko

出版者

The Genetics Society of Japan

雑誌

Genes & Genetic Systems (ISSN:13417568)

巻号頁・発行日

vol.94, no.2, pp.95-98, 2019-04-01 (Released:2019-04-27)

参考文献数

16

被引用文献数

5 5

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We developed microsatellite markers to compare the genetic variation between the putatively cleistogamous Gastrodia takeshimensis (Orchidaceae) and its chasmogamous sister species G. nipponica. We expected low genetic variation in G. takeshimensis in view of its hypothesized cleistogamy. Eighteen primer pairs were developed from a G. takeshimensis genomic DNA library, and their characteristics were tested for G. takeshimensis and G. nipponica. Seven loci were polymorphic in G. nipponica, whereas all loci showed no polymorphism in G. takeshimensis. Genetic diversity was thus not detected in G. takeshimensis, and it seems to have been lost by repeated selfing in the completely closed flower. The 18 markers described here will be useful for investigating the genetic variation between a cleistogamous species and its chasmogamous sister species.