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1.
A new species, Cyperus rheophyticus , is described from seasonally submerged habitats in forest streams and rivers in South West Cameroon (500–1350 m). Cyperus rheophyticus is most similar to C. brevifolius ssp. brevifolius (syn. Kyllinga brevifolius ), a less slender species with a stronger rhizome, larger spikeiets and glumes with a spinose keel; also the anther and achene are larger in that species.  相似文献   

2.
Extreme morphological reduction and convergent evolution can obscure taxonomic relationships. This phenomenon is frequently encountered in Cyperaceae, where characters traditionally used to diagnose genera have been shown to have evolved independently multiple times. The Ethiopian high‐altitude perennial first described as Cyperus clandestinus was subsequently moved to Ficinia because it has spiral glume arrangement, unlike typical Cyperus species, which have distichous glume arrangement. However, this position has remained uncertain as no nutlets have previously been studied to establish the presence or absence of the gynophore – the synapomorphy for Ficinia. We resolve this 140‐year‐old puzzle by describing the morphology of the nutlet, which lacks a gynophore, and use DNA sequence data to resolve the taxon within Cyperus. Cyperus clandestinus was found to be closely related to Remirea maritima and Cyperus cyperoides in the C4Cyperus clade, whose members predominantly have distichously arranged glumes. This provides further evidence for the unreliability of glume arrangement as a character to distinguish between members of the Cyperus and Ficinia clades, whereas gynophore presence is more congruent with molecular data.  相似文献   

3.
? Premise of the study: The understanding of homoplasic structures becomes more relevant when they are complex and define large angiosperm taxa. Inflorescence architecture usually fulfills both features, as happens with Cyperus, a genus with two taxonomical subdivisions characterized either by alternative expressions of Kranz anatomy (C(3) or C(4)) or inflorescence shape (condensed or lax). Those subdivisions are not completely congruent because at least one of these presumed characters has evolved several times. We focused a SEM study on the inflorescence development in species with condensed inflorescences and different photosynthetic anatomy to test the possibility that condensed inflorescences of subgen. Anosporum (C(3) anatomy) have evolved independently from those of subgen. Cyperus (C(4) anatomy). ? Methods: Freshly collected inflorescences of C. entrerianus, C. eragrostis, C. oxylepis, and C. incomtus were studied using stereoscopic and scanning electron microscopy. ? Key results: Condensed inflorescences of Cyperus species with C(3) and C(4) anatomy had differences in structure and development: (1) mature structure, (2) position of second-order branching initiation in the first developmental stage of the inflorescence, (3) main axis development and elongation, and branching development, (4) types of ramifications, (5) phyllotaxis and symmetry. ? Conclusions: Results support multiple origins of condensed inflorescences in Cyperus, based especially on differences in timing during development and elongation of the main axis and branches, branching pattern and phyllotaxis. Structure and development may be the key to using inflorescence morphology as an external feature to distinguish large natural groups within Cyperus based on vegetative anatomy.  相似文献   

4.
Two new subgenera are described and illustrated. Cyperus subgen. Protocyperus has an eucyperoid culm–anatomy and digitate clusters of spikelets. It contains about 100 species. Cyperus subgen. Fimbricyperus has a chlorocyperoid culm anatomy and many stalked spikes giving the habit of a slender Fimbristylis. It is based on a single species, viz. Cyperus subparadoxus Kükenthal.  相似文献   

5.
The phylogeny of Cyperus and allied genera has been reconstructed using cladistic analysis of plastid rbcL gene, rps16 intron, trnL intron, and trnL-F intergenic spacer sequence data in 40 species of tribe Cypereae. Cyperus s.s. as currently circumscribed is not monophyletic because ten cyperoid genera are embedded within it. Eucyperoid Cyperus species (with a C3 anatomy, e.g. C. involucratus ) and the genera Courtoisina , Kyllingiella and Oxycaryum form a clade that is sister to a clade comprising chlorocyperoid species (with a C4 anatomy, e.g. C. papyrus ) and the genera Alinula , Ascolepis , Kyllinga , Lipocarpha , Pycreus , Remirea and Sphaerocyperus . The position of two species is uncertain; C . tenellus is resolved in a clade together with Isolepis although with typical cyperoid spikelets, whereas I. humillima is not resolved near either Isolepis or Cyperus s . l . © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 138 , 145–153.  相似文献   

6.
Papyrus (Cyperus papyrus, Cyperaceae) covers large areas in tropical African wetlands. Analysis of its nutritive value has revealed that crude protein is higher in umbels than culms. Ruminai dry matter digestibility of papyrus is, however, higher in culms than umbels. Both the crude protein and ruminai dry matter digestibility decrease with increasing age of the plant. Values for crude protein and ruminai dry matter digestibility are similar to those reported for the range grasses that constitute the greatest percentage of forage in East Africa. In general, papyrus has some grazing potential and could be used as fodder especially in the dry season when other forage is scarce and of low nutritive value.  相似文献   

7.
Cyperus digitatus var. khasianus is re-instated and a lectotype for the variety and Cyperus hookeri are selected.  相似文献   

8.
From measurements of viability after exposure of tubers to natural overwintering in the soil and 6 weeks exposure at 2 C, species cold tolerance of the tubers was ranked in decreasing order: yellow nutsedge `I' (Cyperus esculentus L.), an ecotype originating in Illinois; yellow nutsedge `G', an ecotype originating in Georgia; and purple nutsedge (Cyperus rotundus L.). The ratios of unsaturated-saturated fatty acids in tuber triglycerides, tuber polar lipids, and leaf polar lipids followed the same order as the cold tolerance rankings, with the most cold-hardy species having the highest ratios. Lipid content was less than 1% of dry weight in purple nutsedge tubers, but was from 5 to 7% in both yellow nutsedge tubers. Starch, sugar, and lipid contents increased significantly in the hardy yellow nutsedge `I' tubers during a 6-week exposure to 2 C, but did not change in the susceptible purple nutsedge tubers; only sugar increased in yellow nutsedge `G' tubers after this treatment. Protein content was not altered by the 2 C treatment in any of the tubers. Apparently, several factors involving starch, sugar, lipids, and fatty acids are related to the differences in tolerance to cold in these species.  相似文献   

9.
Eight new species and one new subspecies of Cyperus subgen. Cyperus (including Mariscus ) are described, illustrated and mapped, viz. C. densibulbosus, C. scabricaulis, C. pluricephalus, C. baobab, C. micromedusaeus, C. gypsophilus, C. somalidunensis, C. recurvispicatus and C. rotundus ssp. divaricatus .  相似文献   

10.
利用光学显微镜对海南莎草属(Cyperus Linnaeus)15个种1个变种的叶下表皮微形态进行了研究。结果显示:(1)该属叶下表皮微形态基本特征如下:长细胞为长筒形、短筒形,少数为近方形,边缘波状、深波状;无短细胞的存在;副卫细胞为高圆屋顶形、圆屋顶形、圆屋顶至三角形或三角形;(2)根据保卫细胞的形态将海南莎草属分为两大类型即保卫细胞两端明显加厚型和保卫细胞两端不明显加厚型;(3)海南莎草属叶下表皮微形态一致,表明莎草属是一个自然类群,但在莎草属种间叶下表皮的长细胞形态、保卫细胞及副卫细胞形态、气孔长宽等存在一定的差异,可作为本属种间分类鉴别的参考依据。  相似文献   

11.
Thind , K. S., and G. S. Rawla . (Panjab U., Chandigarh, India.) A new fungus on Cyperus iria. Amer. Jour. Bot. 48(10): 859–862. Illus. 1961—Duosporium cyperi gen. et sp. nov., collected on Cyperus iria Linn., is characterized by the production of 2 types of conidia, macroconidia and microconidia. The macroconidia are straight, cylindrical, triseptate, with their middle cells dark brown, long, thick-walled, and end cells much paler or subhyaline, short, thin-walled, the middle and the end cells being equally wide. The microconidia are nonseptate, spherical, dark brown, prominently verrucose, and produced apically on the conidiophores like the macroconidia; occasionally also formed as secondary conidia on germinating 3-septate macroconidia in culture. The formation of 2 distinct types of conidia in Duosporium and the features of its macroconidia characteristically differentiate it from its close relative Helminthosporium, although Duosporium. cyperi is not unique among fungi in producing 2 types of conidia.  相似文献   

12.
This study examined the performance of pilot-scale vertical subsurface flow constructed wetlands (VSF–CWs) planted with three indigenous plants, i.e. Typha latifolia, Cyperus alternifolius, and Cynodon dactylon, in removing heavy metals from secondary treated refinery wastewater under tropical conditions. The T. latifolia-planted VSF–CW had the best heavy metal removal performance, followed by the Cyperus alternifolius-planted VSF–CW and then the Cynodon dactylon-planted VSF–CW. The data indicated that Cu, Cr, Zn, Pb, Cd, and Fe were accumulated in the plants at all the three VSF–CWs. However, the accumulation of the heavy metals in the plants accounted for only a rather small fraction (0.09–16%) of the overall heavy metal removal by the wetlands. The plant roots accumulated the highest amount of heavy metals, followed by the leaves, and then the stem. Cr and Fe were mainly retained in the roots of T. latifolia, Cyperus alternifolius, and Cynodon dactylon (TF < 1), meaning that Cr and Fe were only partially transported to the leaves of these plants. This study showed that VSF–CWs planted with T. latifolia, Cyperus Alternifolius, and Cynodon dactylon can be used for the large-scale removal of heavy metals from secondary refinery wastewater.  相似文献   

13.
在盛装容积为100L富营养化生活污水的陶缸中放置泡沫塑料板作为浮体材料,并用有孔塑料小杯作为漂浮植物修复系统,在温室内种植风车草、彩叶草和茉莉进行植物净化试验。分别测定了污水中的总磷(T-P)、水溶性磷(S-P)、铵态氮(NH4^+-N)、硝态氮(NO3^--N)和总氮(T-N)在种植这3种植物过程中的含量变化情况。结果表明,这3种植物经28d生长之后,风车草和彩叶草生长良好,生物量大,其干重分别是初始种植时的285.8%和371.4%,而茉莉生长较差,生物量增加少。其干重只是初始种植时的125%.风车草、彩叶草和茉莉对污水中的总氮的去除率分别为68.0%、62.0%和45.0%,对硝态氮的去除率分别为98.0%、80.0%和92.0%,对总磷的去除率分别为78.0%、66.0%和55.0%,对CODCr的去除率分别为90.6%、90.5%和88.0%.风车草和彩叶草在飘浮植物修复系统栽培中具有良好的去污效果。  相似文献   

14.
The effects of Cd, Ni and Pb on the growth, chlorophyll (Chl) and protein contents, and content of proteases of potted weed plants Cyperus difformis, Chenopodium ambrosioides and Digitaria sanguinolis were determined. The three heavy metals inhibited the shoot growth but were less suppresive to root growth. They also lowered leaf Chl content. The changes in root and shoot protein and proteases contents of weeds were interrelated. The heavy metal additions to soil increased their contents in both roots and shoots, several times more in roots than in shoots. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
不同基质和不同植物对人工湿地净化效率的影响   总被引:13,自引:0,他引:13  
魏成  刘平  秦晶 《生态学报》2008,28(8):3691-3697
实验通过建立不同模式的小型湿地系统研究了不同基质和不同的植物组合对人工湿地净化效率和效率稳定性的影响.结果表明,种植植物的湿地系统比没有植物的湿地系统净化效率高,沙土混合基质比卵石基质净化效率高;旱伞草和美人蕉组合以及旱伞草、美人蕉和芦苇3种植物的组合湿地系统比单一旱伞草湿地系统的净化效率更高;小粒径基质和混合种植湿地系统能够保持较稳定的净化效率.  相似文献   

16.
More than 18 000 archaeological sites have been identified, and a dozen rock shelter sites investigated in the Zeekoe Valley, Upper Karoo, South Africa, but no work has been performed to date regarding edible plant remains. A baseline for understanding potential contribution of plants to the Zeekoe Valley diet is crucial for developing models of land use and mobility patterns for Late Stone Age (LSA) inhabitants, particularly since ethnographically known foragers in Botswana, some 800 km to the north, are as much as 80% dependent on plant foods for their survival. Since native foraging groups are long extinct in this semi-arid region with abundant natural springs, a rigorous investigation of botanical and ethnohistoric literature forms the groundwork for field investigations where direct ethnographic observation is no longer an option. First, edible species in the study area are identified in the literature. They are then sought on the ground with the aid of local informants whose families have resided in the valley for generations. It appears as though some knowledge of local plants gained from native foragers 150 years ago or more has remained in Afrikaans families passed down from landowning parent to child. On the ground, collection and middle range experimentation was followed by basic nutritional analysis. These measures were then used to compare foraging efficiency to measures from extant foraging groups. While dozens of edible species were identified, five plant species formed the focus of this study: Slymstock Uintjie (Albuca canadensis); Boesman Uintjie (Cyperus usitatus, Cyperus fulgens); Jakkalsbosberry (Diospyros austro-africana); Rooi wortel (Pelargorium sidoides); and Osbossie (Talinum caffrum). Results suggest native foraging groups, now extinct in the vicinity, may have been 60% or more dependent on plant food resources, despite abundance of game in the area and in the archaeological record.  相似文献   

17.
山东莎草属植物果实形状及果皮微形态研究   总被引:1,自引:0,他引:1  
利用扫描电镜对山东分布的18种莎草属植物的果实形状及果皮微形态进行了观察研究。结果表明,莎草属植物果实为椭圆状、倒卵状或卵状三棱形,顶端具柱状或锥状短喙;果皮微形态可分为:网-疣复合纹饰、网状纹饰、疣状纹饰和无规则突起纹饰4种类型;果皮微形态类型的划分与基于宏观形态特征的传统分类关联较小,但在该属形态相近的种间存在明显差异,可作为种间划分的依据。果皮微形态证据支持将水莎草属(Juncellus)、砖子苗属(Mariscus)和断节莎属(Torulinium)归入莎草属(Cyperus)的分类观点。  相似文献   

18.
金华地区秋旱作物田杂草生态相似关系研究   总被引:13,自引:1,他引:12  
对浙江金华地区秋旱作物田17个样点的杂草优势度等级进行了七级目测调查,计测了22种主要杂草的生态位宽度和生态位重叠值,作出了反映它们间生态学相似程度的最小生成树。结果表明,马唐Digitaria sanguinalis、狗尾草Stearia viridis、千金子Leptochloa chinensis、碎花莎草Cyperus iria、牛筋草Eleusine indica、石胡荽Centiped  相似文献   

19.
Owen  R.B.  Renaut  R.W.  Hover  V.C.  Ashley  G.M.  Muasya  A.M. 《Hydrobiologia》2004,518(1-3):59-78
Lakes Bogoria and Baringo lie in a semi-arid part of the Kenya Rift Valley between 0° 15′–0° 30'N and 36° 02′–36° 05′E. Nevertheless, the area around these lakes contains numerous wetland systems that have been formed: along lake shorelines; along faults where hot, warm and cold springs have developed; and along river systems that cross the rift floor. Six major types of wetland are recognized: Proximal Hot Springs; Hot Spring Marshes; Blister Wetlands; Typha and Cyperus papyrus Swamps; Floodplain Marshes; Hypersaline Lake Littoral Wetlands; and Freshwater Lake Littoral Wetlands. These show significant variability in terms of geomorphic setting, water chemistry, temperature, plant communities and diatom floras. They are variously dominated by macrophytes, such as Cyperus laevigatus, Typha domingensis and Cyperus papyrus. In some cases macrophytes are absent. In hot spring settings and in hypersaline lake littoral zones bacterial mats are common. Although absent in some samples, diatoms occur in at least parts of all of the wetlands, varying in diversity, abundance and species composition. Canonical correspondence analysis indicates that diatom floras show a close relationship with pH, temperature, and specific conductivity, with other environmental variables such as Si and nitrate being of secondary importance. Common diatoms include: Anomoeoneis sphaerophora var. guntheri, Navicula tenella, N. cuspidata, and Nitzschia invisitata in hot springs, where diversity is generally low and abundance is variable. Other wetland types contain distinctive diatom floras that variously include: Fragilaria brevistriata, Gomphonema parvulum, Navicula tenelloides, Nitzschia communis, N. latens, N. sigma, Rhopalodia gibberula, and Stauroneis anceps.  相似文献   

20.
The sesquiterpene caryophyllene in its alcohol form has been identified for the first time from the essential oil of the tubers of Cyperus rotundus Linn. The structure of the alcohol has been identified by spectroscopic and chemical methods. Bioefficacy of the oil and its hydrocarbon, ketonic and alcoholic fractions is reported for maize and mungbean.  相似文献   

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