36 research outputs found

    6-Year Periodicity and Variable Synchronicity in a Mass-Flowering Plant

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    Periodical organisms, such as bamboos and periodical cicadas, are very famous for their synchronous reproduction. In bamboos and other periodical plants, the synchronicity of mass-flowering and withering has been often reported indicating these species are monocarpic (semelparous) species. Therefore, synchronicity and periodicity are often suspected to be fairly tightly coupled traits in these periodical plants. We investigate the periodicity and synchronicity of Strobilanthes flexicaulis, and a closely related species S. tashiroi on Okinawa Island, Japan. The genus Strobilanthes is known for several periodical species. Based on 32-year observational data, we confirmed that S. flexicaulis is 6-year periodical mass-flowering monocarpic plant. All the flowering plants had died after flowering. In contrast, we found that S. tashiroi is a polycarpic perennial with no mass-flowering from three-year individual tracking. We also surveyed six local populations of S. flexicaulis and found variation in the synchronicity from four highly synchronized populations (>98% of plants flowering in the mass year) to two less synchronized one with 11–47% of plants flowering before and after the mass year. This result might imply that synchrony may be selected for when periodicity is established in monocarpic species. We found the selective advantages for mass-flowering in pollinator activities and predator satiation. The current results suggest that the periodical S. flexicaulis might have evolved periodicity from a non-periodical close relative. The current report should become a key finding for understanding the evolution of periodical plants

    Systematic analysis of mitochondrial genes associated with hearing loss in the Japanese population: dHPLC reveals a new candidate mutation

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    <p>Abstract</p> <p>Background</p> <p>Variants of mitochondrial DNA (mtDNA) have been evaluated for their association with hearing loss. Although ethnic background affects the spectrum of mtDNA variants, systematic mutational analysis of mtDNA in Japanese patients with hearing loss has not been reported.</p> <p>Methods</p> <p>Using denaturing high-performance liquid chromatography combined with direct sequencing and cloning-sequencing, Japanese patients with prelingual (N = 54) or postlingual (N = 80) sensorineural hearing loss not having pathogenic mutations of m.1555A > G and m.3243A > G nor <it>GJB2 </it>were subjected to mutational analysis of mtDNA genes (<it>12S rRNA</it>, <it>tRNA</it><sup><it>Leu(UUR)</it></sup>, <it>tRNA</it><sup><it>Ser(UCN)</it></sup>, <it>tRNA</it><sup><it>Lys</it></sup>, <it>tRNA</it><sup><it>His</it></sup>, <it>tRNA</it><sup><it>Ser(AGY)</it></sup>, and <it>tRNA</it><sup><it>Glu</it></sup>).</p> <p>Results</p> <p>We discovered 15 variants in <it>12S rRNA </it>and one homoplasmic m.7501A > G variant in <it>tRNA</it><sup><it>Ser(UCN)</it></sup>; no variants were detected in the other genes. Two criteria, namely the low frequency in the controls and the high conservation among animals, selected the m.904C > T and the m.1105T > C variants in <it>12S rRNA </it>as candidate pathogenic mutations. Alterations in the secondary structures of the two variant transcripts as well as that of m.7501A > G in <it>tRNA</it><sup><it>Ser(UCN) </it></sup>were predicted.</p> <p>Conclusions</p> <p>The m.904C > T variant was found to be a new candidate mutation associated with hearing loss. The m.1105T > C variant is unlikely to be pathogenic. The pathogenicity of the homoplasmic m.7501T > A variant awaits further study.</p

    Kakishima, M.

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    Laurobasidium hachijoense, comb. nov.(Cryptobasidiaceae) causing aerialroot-like galls on Cinnamomum japonicum in Japan

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    A new combination, Laurobasidium hachijoense, is proposed to accommodate Exobasidium hachijoense from Japan, producing aerialroot-like galls on stems of Cinnamomum japonicum. This combination is based on the presence of a gastroid-like sporulation on the surface of the galls, and is supported also by the host-plant specialization and molecular data.A fungus producing aerialroot-like galls on the trunks and stems of Cinnamomum japonicum (Lauraceae) was found in 1984 and was described as a new species, Exobasidium hachijoense Y. Otani et al. (Iijima et al. 1985). This species is similar to E. lauri Geyl. on stems of Laurus azorica (Seub.) Franco and L. nobilis L. (Geyler 1874) in gall and sorus structures, but different in morphological features of basidia—the number of sterigmata per basidium and the size of basidium (Iijima et al.1985

    Clinoconidium globosum, nom. nov. (Cryptobasidiaceae) producing galls on fruits of Cinnamomum daphnoides in Japan

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    A new name, Clinoconidium globosum, is proposed to accommodate Sphacelotheca cinnamomi from Japan, producing galls on fruits of Cinnamomum daphnoides (Lauraceae). This decision is based on observations of gastroid sporulation in peripheral lacunae of the host galls and basidiospore morphology. This species is characterized by small, globose basidiospores. Its morphological features are described based on newly collected specimens. Results of recently published phylogenetic analyses also support this new name

    (137)Cs concentrations in foliose lichens within Tsukuba-city as a reflection of radioactive fallout from the Fukushima Dai-ichi Nuclear Power Plant accident

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    (137)Cs concentrations in ten species of foliose lichens collected within Tsukuba-city in August 2013 ranged from 1.7 to 35 kBq/kg. The relationships between (137)Cs in two dominant species, Dirinaria applanata and Physcia orientalis, and the air dose rate (muSv/h) at the sampling sites were investigated. (137)Cs in P. orientalis measured about 1 year after the Fukushima nuclear accident was correlated (r(2) = 0.80) more closely with the air dose rate than those measured after about 2 years (r(2) = 0.65), possibly demonstrating its continued value as a biomonitor to reflect ambient fall-out levels. In contrast, those of Dirinaria applanata were not correlated with the air dose rate in either year

    (137)Cs concentrations in foliose lichens within Tsukuba-city as a reflection of radioactive fallout from the Fukushima Dai-ichi Nuclear Power Plant accident

    No full text
    (137)Cs concentrations in ten species of foliose lichens collected within Tsukuba-city in August 2013 ranged from 1.7 to 35 kBq/kg. The relationships between (137)Cs in two dominant species, Dirinaria applanata and Physcia orientalis, and the air dose rate (muSv/h) at the sampling sites were investigated. (137)Cs in P. orientalis measured about 1 year after the Fukushima nuclear accident was correlated (r(2) = 0.80) more closely with the air dose rate than those measured after about 2 years (r(2) = 0.65), possibly demonstrating its continued value as a biomonitor to reflect ambient fall-out levels. In contrast, those of Dirinaria applanata were not correlated with the air dose rate in either year
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