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Taxonomic Studies on Carex Sect. Rhomboidales (Cyperaceae) in China

Author: LingLingLing
Tutor: JinXiaoFeng
School: Hangzhou Normal University
Course: Botany
Keywords: The rhombic If Carex Group Leaf epidermis Leaf anatomy Achene micromorphology Taxonomic revision
CLC: Q949
Type: Master's thesis
Year: 2011
Downloads: 29
Quote: 1
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Abstract

Cyperaceae Carex sedge genus Carex is a large genus of angiosperms, about 2,000 of the world, and about 500 species, widely distributed throughout the country. Due to the widely distributed, and a wide variety of name confusion, holotype dispersion, classification and identification of a very difficult, there are larger issues and serious differences, especially in the division of the species, its level and geographic distribution. The diamond-shaped fruit, not taxonomists genus Carex Carex group Carex sect Rhomboidales division of different perspectives, there is a dispute the ownership of the group defined species. The extensive literature inspection, wild-collected specimens identified the basis, the concept of population for guidance, combined with leaf epidermal morphology, leaf anatomical structure and achenes micro-morphological characteristics, a comprehensive revision of the group, and to explore its systematics and classification significance. The main findings are as follows: 1 leaf epidermal morphology and systematics and taxonomic significance observed 53 samples (domestic diamond-shaped fruit Carex group of 39 species, 2 subspecies, 1 variety) Leaf Epidermis, the group of the leaf epidermis cells mostly rectangular, the anticlinal walls mostly sinuate, stomatal basic distribution of the lower epidermis, the upper and lower epidermis sometimes with siliceous mastoid, the epidermal appendages be divided into two types of spike and bristle. Samples of different localities, the Leaf Epidermis no significant difference between the exhibit stability within species. Should be classified based on morphological characteristics and leaf epidermis observation indicates the proboscis Carex C. longerostrata and fake proboscis Carex Cpseudolongerostrata Sect. Rhomboidales s str. The peace Ling If sprouts the grass cmacrandrolepis and the sharp fruit Carex C. tatsutakensis and Sect. Rhomboidales different members, China Carex C. chinensis and its variants Dragon odd Carex C. chinensis var. longkiensis members of the Qinling the Carex Cdiplodon and Sect. Rhomboidales significantly different for the other members of the group. Leaf epidermal characters between the group of closely related species exist significant difference, can be used as the basis of the distinction between species or taxa. Leaf anatomical structure and its systematic and taxonomic significance observed 53 samples (domestic diamond-shaped fruit Carex group of 39 species, 2 subspecies 1 variant) leaf anatomical structure, results of display crosscutting appearance of the leaves roughly as \V \The epidermal appendages divided into verrucous table fur two, subepidermal mesophyll cells with varying degrees of differentiation. Leaf anatomical features found samples of the different populations showed intraspecific stable bubbly cell layers in the cross-section shape, epidermal appendages midrib bundle sheath cell layers, on the level of development of sclerenchyma sex. The leaf anatomical feature also supports the to the the long beak Carex and fake proboscis Carex placed Sect. Rhomboidales leaf anatomical characteristics of a clear distinction between related species can be distinguished morphologically similar species. Achene micromorphology and its systematic and taxonomic significance of the 44 samples (domestic diamond-shaped fruit sprouts grass group of 33 species, 2 subspecies 1 variant) achene morphology of the scanning electron microscope achene shape mostly egg shaped or obovate, with straight or curved beak, stipitate edge on constricted or not constricted facet concave; fruit surface cells are generally irregular 4-7 gon obvious anticlinal walls its type can be divided into straight, light wave, wave and dark wave; most species with a centrosome the siliceous station concave, flat or convex. Achene micromorphology found achene appearance and peel surface ornamentation exhibit stability within species from different localities of the populations. Achene surface morphology proved the Carex and sharp fruit of peace Ling fruit Carex Sect. Rhomboidales s str. Significantly different. Achene surface micro-morphological differences between the group of closely related species, can be used as the basis of the distinction between species or taxa. 4, classification revised the Leaf Epidermis related taxa leaf anatomical structure and achene morphology, and access to large quantities of specimens (holotype), the combination of all of the results of the diamond-shaped fruit Carex group comprehensive revision. Recognition of this group of 34 kinds, including the discovery of a new species of Qiannan Carex C. chorda the sharp teeth Carex C. canina, and streamside Carex C. rivulorum, new combinations of variants Funing Carex of C. brevicuspis var. funingensis and Gao Carex C. canina var the kaoi and new combinations subsp subspecies C. harlandii of of. hoozaensis of C. takasagoana and Gansu habitat Mountain Carex the C. longqishanensis merge curved handle Carex C. manca base spend Carex C. basiflora as Taibai Mountain the Carex C. taipaishanica the synonyms.

Taxonomic Studies on Carex Sect. Rhomboidales (Cyperaceae) in China

Abstract

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