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Summary. Nuclear DNA contents, automated karyotype analyses, and sequences of rDNA spacers have been determined for the species of Vicia belonging to sect. Peregrinae, as well as for V. mollis. The phylogenetic data generated from the comparison of rDNA sequences and karyomorphological results would both indicate that Vicia mollis is a sister group to sect. Peregrinae. The relationships among the species belonging to the Peregrinae section and species enclosed in sections Faba, Narbonensis, and Bithynicae have been also investigated: a clade including V. mollis and sect. Peregrinae is a sister group to a clade including V. bithynica and sect. Narbonensis. With our choice of outgroup, Vicia faba (including subsp. paucijuga) is external to the above mentioned inclusive group. Correspondence and reprints: Dipartimento di Agrobiologia ed Agrochimica, Università della Tuscia, via San Camillo de Lellis, 01100 Viterbo, Italy.  相似文献   

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Elachista fucicola (Velley) Areschoug (Elachistaceae, Phaeophyceae) is newly recorded from Japan, and compared with three previously described species, Elachista coccophorae Takamatsu, Elachista mollis Takamatsu and Elachista okamurae Yoshida. All species showed direct‐type life histories in culture without sexual fusion. Prostrate filaments of E. fucicola formed globular plurilocular zoidangia similar to those reported from Atlantic isolates of this species. However, these were different from uniseriate plurilocular zoidangia of the three Japanese species. Furthermore, the position of a meristematic region in assimilatory filaments and the morphology of paraphyses can easily distinguish these from E. fucicola. Previously emphasized differences in cell length : width ratios in assimilatory filaments showed only slight differences. Elachista coccophorae is characterized by thick‐walled assimilatory filaments and curved paraphyses, and the absence of downwardly growing rhizoidal filaments. Elachista mollis and E. okamurae are very similar. However, germlings from plurizoids formed on erect filaments of E. mollis showed characteristic pseudodiscoid growth in culture. Halothrix coccophorae Ohta and Elachista zosterae Noda are reduced to synonyms of E. coccophorae and E. mollis, respectively.  相似文献   

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A new subspecies, Klasea serratuloides (DC.) Greuter & Wagenitz subsp. karamanica B. Dogan & A. Duran (Asteraceae), is described and illustrated from Anatolia, Turkey. The subspecies grows on stony places in the Ayranc? and Ermenek district (C4 Karaman Province), Ere?li district (C5 Konya province) and Uluk??la (C5 Ni?de province) in the central and south Anatolia transition zone. It is morphologically similar to K. serratuloides subsp. serratuloides. Diagnostic morphological characters from closely similar taxa are discussed and arranged in a key. Ecology and conservation status of the subspecies is also presented. In addition, the geographical distribution of the new subspecies and other related species is mapped. The pollen morphology and achene surface of K. serratuloides subsp. karamanica and K. serratuloides subsp. serratuloides were examined by SEM.  相似文献   

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The karyotypes of diploidP. fragilis subsp.villosus (2n = 2x = 14) and tetraploid subsp.secaliformis (2n = 4x = 28) were studied by Giemsa C- and N-banding, and AgNO3 staining and compared with the karyotype of subsp.fragilis (2x). The complements of subsp.villosus and subsp.fragilis were similar, with 8 metacentric and 6 SAT-chromosomes, one metacentric and two submetacentric pairs, with small to minute, polymorphic, heterochromatic satellites. The complement of subsp.secaliformis on the whole agreed with a doubling of the complement of diploidP. fragilis, suggesting autopolyploidy. Only the presence of 12 nucleoli in interphases identified 6 SAT-chromosome pairs. In subsp.villosus one or two extra micronucleoli indicated a chromosome pair with very low nucleolusforming activity, bringing the number of SAT-chromosome pairs to 4. This number may be a characteristc ofPsathyrostachys. Besides very small, inconsistently observed bands, the C-banding pattern consisted of 0–3 small bands per chromosome at intercalary and terminal locations, and at NORs. The level of banding pattern polymorphism was low, but enough to indicate that the taxa are outbreeders. Similarities in chromosome morphology and C-banding patterns identified homology of all chromosomes of subsp.villosus, but for 12 pairs only in subsp.secaliformis. Between plants, reliable identification of homology and homoeology (subsp.secaliformis) was possible only for the SAT-chromosomes and the shortest metacentrics. Chromocentres were very small and the amount of constitutive heterochromatin was low. N-banding stained chromosomes uniformly. The basic karyotypes of theP. fragilis taxa were similar to those ofP. juncea, P. lanuginosa, andP. stoloniformis supporting a close relationship and the presence of a common genome, N. NORs had different nucleolus-forming activities. Meiotic analysis demonstrated a high level of bivalent pairing in the three taxa. A chromosomal rearrangement was suggested in subsp.villosus. The low multivalent frequency in subsp.secaliformis indicates the presence of a pairing regulation mechanism. The majority of chiasmata were interstitial. Pollen grain size discriminated between diploid and tetraploid taxa. The existence of a diploid cytotype of subsp.secaliformis is supported by pollen measurements of herbarium material.  相似文献   

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A new species of Crocus sect. Crocus is described as an endemic of Elba Island (Tuscan Archipelago, Italy): C. ilvensis Peruzzi & Carta sp. nov. (2n=8). The new species was wrongly referred to C. corsicus Vanucchi (2n=18), C. etruscus Parl. (2n=8) or C. vernus Hill. subsp. vernus (2n=8, 16) by previous authors. Its karyotype structure, asymmetry and chromosome dimensions show affinity with C. etruscus, and no clear relations with other related taxa. From a morphological point of view, C. ilvensis appears intermediate between C. etruscus and C. vernus subsp. vernus, showing however a peculiar combination of character‐states. The new species is completely allopatric with other Crocus sect. Crocus taxa and its possible role in the origin of tetraploid races of C. vernus is discussed.  相似文献   

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So far considered as endemic to Greece, Hieracium umbrosum subsp. abietinum is reported as new for the Italian flora. Its presence has been noted on the Pollino National Park (S Italy). Morphological, ecological and taxonomical notes are given. This discovery increases the list of taxa showing an amphi-Adriatic distribution.  相似文献   

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Abelmoschus enbeepeegearense J. John et al. is a new species occurring at low elevations in the Western Ghats of India, comprising Kerala, Karnataka and Tamil Nadu. The taxon is morphologically allied to A. moschatus subsp. moschatus, A. moschatus subsp. tuberosus and A. crinitus, but easily distinguishable by virtue of its orthotropic branching, 3–5‐angled leaves, glandular hairy plant body with whitish waxy secretions, glandular non‐setose epiclayx segmens which is more than eight in number and ovate hirsute fruits with a short mucro at the apex. It can be crossed with all three taxa with varying degree of success, but the hybrids are sterile. The material belonging to it was earlier identified as and placed under A. moschatus Medik. The taxon is described and illustrated with notes on its phenology, ecology and distribution. In additions, a key to all Abelmoschus taxa occurring in India is provided.  相似文献   

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The antibacterial activity of the leaf essential oil of Blumea mollis was assayed against 14 clinically isolated bacterial strains on Muller–Hinton Agar medium and Muller–Hinton Agar medium with 5% sheep blood. The essential oil had promising antibacterial activity against all the bacterial strains tested. The highest mean zone of inhibition and lowest values of minimum inhibitory concentration were recorded against methicillin-resistant Staphylococcus aureus followed by beta hemolytic Streptococcus pyogenes. The Gram-positive bacteria were more sensitive than Gram-negative bacteria. Among the bacterial strains tested, Psudomonas aeruginosa was resistant to the essential oil. The results of the present study suggest that the essential oil of B. mollis is one of the new medicinal resources as an antibacterial agent against the bacterial strains tested.  相似文献   

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The closely related genera Carestiella, Schizoxylon and Stictis (Stictidaceae, Ostropales, Ascomycota) are revised in northern Scandinavia, and a revised phylogenetic hypothesis, including all seven species of this group in the area, is presented. A key to the species of Stictis s. lat. (including Carestiella, Schizoxylon and Stictis) in Northern Scandinavia is presented. S. albescens and S. confusum are described as new to science, and the new name S. brunnescens is introduced for S. mollis ssp. populorum, when treated as a distinct species. C. socia and S. albescens are the only representatives of their genera in northern Scandinavia, but a total of five species of Stictis are present in the area (S. brunnescens, S. confusum, S. mollis, S. populorum and S. radiata). Substantial within-species variation in ascoma morphology and wall pigmentation is revealed and discussed, and found to correlate with fungal lifestyles; optional lichenization apparently affects several details in fungal anatomy and morphology.  相似文献   

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In the framework of our studies on Lamiaceae from the eastern Iberian Peninsula, for the forthcoming fourth volume of Flora valentina, a new infraspecific arrangement is proposed here for the Iberian endemic Teucrium thymifolium. Besides the type subspecies, T. thymifolium subsp. thymifolium, which is widely distributed through the eastern Iberian Peninsula, two new nomenclatural combinations are established: (i) T. thymifolium subsp. fraternum (Pau) M.B. Crespo, M.A. Alonso & Mart.-Azorín (= T. terciae), for the thermophilous populations growing in SE Murcia province, and (ii) T. thymifolium subsp. hervieri (Briq. & Debeaux) M.B. Crespo, M.A. Alonso & Mart.-Azorín, for Subbaetic inland populations from where the provinces of Albacete, Jaén and Granada come into contact. Nomenclatural types and data on distribution and ecology are reported for all accepted subspecies, including the designation of a lectotype for T. thymifolium subsp. hervieri. Furthermore, relationships of the latter to the recently described T. moleromesae Sánchez Gómez et al. are briefly discussed, both taxa being treated here in synonymy.  相似文献   

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Hieracium pallidum subsp. aetnense Gottschl., Raimondo & Di Grist. is described and illustrated. H.pallidum is considered as an intermediate species between H. schmidtii and H. racemosum (“schmidtii>racemosum”) and is placed in H. sect. Grovesiana. By consequence, H.lanudae Gottschl. is transferred to H. pallidum as H. pallidum subsp. lanudae (Gottschl.) Gottschl., Raimondo & Di Grist. A key for the three recognised subspecies of H. pallidum is provided.  相似文献   

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Agave manantlanicola, a new endemic species from the high altitude mountains of the Sierra de Manantlán in western Mexico, is described and illustrated. The species belongs to the subgenus Littaea and Gentry’s Amolae group. The new species is compared to other morphologically similar species from western Mexico, including Agave attenuata subsp. attenuata, A. attenuata subsp. dentata, A. bakeri, A. chazaroi, and A. vazquezgarciae. Information about its distribution, habitat, and conservation status is included.  相似文献   

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马会雷  张婷凤  周瑞莲  张玥 《生态学报》2018,38(10):3504-3513
在自然条件下,测定分析了夏季和秋季静风天及秋季大风天,海岸沙丘不同坡向环境因子及滨麦株高、叶片叶绿素含量、土壤含水量和光合日变化特性,以期明晰滨麦响应不同风速环境的生理调控机理。结果表明,不同坡向环境异质性明显,滨麦形态可塑性强。海岸迎风坡风大、温度低、湿度大,滨麦植株低矮、叶绿素含量较高;背风坡温度高、土壤干旱、空气流动差,滨麦植株高大,叶绿素含量低。在夏秋季静风天,迎风坡和背风坡滨麦叶片Pn出现光合"午休"现象,但迎风坡滨麦日均Gs、Tr、Pn均显著高于背风坡;而在秋季大风天,迎风坡和背风坡滨麦叶片Pn"午休"现象消失,并且背风坡滨麦日均Pn、Tr、Gs均显著高于迎风坡滨麦。同坡向相比,秋季大风天迎风坡滨麦日均Pn、Tr、Gs明显较秋季静风天低,而背风坡滨麦日均叶片Pn、Tr、Gs却较静风天分别增高126%、66.3%、134%。强海风吹袭引发迎风坡温度降低、滨麦叶片摇摆、气孔导度降低导致Pn下降,而强海风使背风坡空气流动加快、温度降低、气孔导度增大、"午休"消失使Pn增高。不同坡向滨麦对不同海风风速的适应表现出明显的光合生理可塑性,它在滨麦适应不同风力、提高其光合速率和增加物质积累上具有重要作用。而滨麦的形态和光合生理可塑性可能是其在不同海风强度下生存、生长、实现种群扩张的重要生理调控机理,这一特性在未来作物、牧草和树木抗风、抗盐育种中具有重要应用价值。  相似文献   

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A new species, Centaurea rahiminejadii Negaresh (Asteraceae) in C. sect. Cynaroides Boiss. ex Walp., is described and illustrated from the Kermanshah Province, west Iran. It is morphologically similar to Centaurea regia Boiss. subsp. regia. Diagnostic morphological of this and closely related taxa are discussed and presented. The ecology, habitat and conservation status of the new species are also described. In addition, Centaurea regia subsp. cynarocephala (Wagenitz) Wagenitz is reported as a new record to the flora of Iran. Finally, the geographic distribution of the new species and closely related species is presented and mapped.  相似文献   

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