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作者在进行四川、云南硅藻分类研究中,发现了星肋小环藻的一新变种,定名为星肋小环藻线纹变种(Cyclotella asterocoaata var.striata),为编写《中国硅藻志》提供资料。 相似文献
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Cyclotella ortentalis sp. nov, is described from an epilithic sample taken in Lake Imha, located in Kyungsangbuk-do. South Korea. The species is characterized by a conspicuous and short costa regularly extending from each marginal fultoportula to the valve margin. It can be included in the Cyclotella stelligeroid group. The new species can be separated from the most similar species C. stelligera Cleve et Grunov var. stelligera by the more distant position of marginal fultoportulae from the valve margin, the external long tubes of fultoportulae and having short costae. It differs from C. stelligera var. robusta Must, and var. hyalina Hust., in having much denser marginal striae; from C. glomerata H. Bachm., C. pseudostelligera Hust., C. stelligeroides Must, and C. woltereckii Hust., in its much larger valve, coarser marginal striae and short costae with fultoportulae. 相似文献
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本文仅报道属于中心纲硅藻的二新种和一新变种以及对菱形小环藻Cyclotella rhomboideo-elliptica Skuja(1937)特征的补充和修改。 1.罗兹直链藻西藏变种 (新变种) Melosira roeseana var.xizangensis 相似文献
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Yu Liu Tian-Gang Luan Ning-Ning Lu Chong-Yu Lan 《植物学报(英文版)》2006,48(2):169-180
Fluoranthene Is one of the polynuclear aromatic hydrocarbons with four benzene rings. Because of Its toxicity, mutagenlclty, and carclnogenlclty, fluoranthene Is on the black lists of 129 and 68 priority pollutants established by US Environmental Protection Agency and the People＇s Republic of China, respectively. In recent years, the amount of fluoranthene In the aquatic environment has been Increasing with Increases In anthropogenlc discharge. Based on the biological investigation of tidal water In the Futlan mangrove, Cycioteila ~aspla was selected as the dominant algal species to determine the toxicity of fluoranthene towards C. caspla alga and to Investigate the blodegradatlon of fluoranthene by C. caspla under pure culture. The toxicity experiment showed that the 96-h EC50 value for fluoranthene was 0.2 mg/mL. Four parameters, namely C. caspla algal growth rate, chlorophyll （Chl） a content, cell morphology, and superoxlde dlsmutase （SOD） activity, were chosen as Indices of toxicity and were measured at 6 d （144 h）. The results showed that： （Ⅰ） the toxicity of fluoranthene towards C. caspla alga was obvious; （Ⅱ） C. caspla algal growth rate and Chl a content decreased with Increasing concentrations of fluoranthene; and （Ⅲ） the rate of cell deformation and SOD activity Increased with Increasing concentrations of fluoranthene. The blodegradatlon experiment showed that： （Ⅰ） the rate of physical degradation of fluoranthene was only 5.86%; （Ⅱ） the rate of blodegradatlon of fluoranthene on the 1st and 6th days （l.e. at 24 and 144 h） was approximately 35% and 85%, respectively; and （Ⅲ） the blodegradatlon capability of C. caspla alga towards fluoranthene was high. It is suggested that further Investigations on the toxicity of fluoranthene towards algae, as well as on algal blodegradatlon mechanisms, are of great Importance to use C. caspla as a biological treatment species In an organic wastewater treatment system. 相似文献
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Rex L. Lowe 《Journal of phycology》1975,11(4):415-424
Cyclotella atomus Hust., C. meneghiniana Kütz., C. comta (Ehr.) Kütz., C. antiqua W. Sm., C. michiganiana Skv., C. ocellata Pant., C. glomerata Bachmann, C. pseudostelligera Hust., and C. stelligera (Cleve et Grun.) V. H., were selected for ultrastructure investigations on the basis of their ready availability. Specimens were examined employing both transmission and scanning electron microscopy. Strutted processes, labiate processes, spines and other special features were surveyed in all species. On the basis of these observations the species of Cyclotella observed seem to be in one of 3 morphological groups, the meneghiniana group, the comta group, and the stelligera group. 相似文献
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eterachopsis was proposed by the senior author as an independent genus ofthe family Aspleniaceae in 1940 with 2 species. Since then much study on its morphology, anatomy, gametophyte and palynology has been carried out by Nayar, Bir, Chandra & Nayar and Chang et al., and they are of the opinion that the genus like Ceterach, is a comparatively primitive element in the family Aspleniaceae. The queer zigzag patern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae, and also suggests its antiquity in evolution. So far only 3 species (C. dalhousiae, C.paucivenosa and C. magnifica) are recognized, the former from W. Himalayas, alsoknown from Africa, while the latter two from W. S. China (Yunnan). However, inthe past forty years the Chinese botanists have discovered 2 more species as new in N.W. Yunnan, thus bringing the total known species of the genus up to 5. The presentpaper is a brief summary on the genus Ceterachopsis, which will be published in detailin the Flora Sinica vol. 4. Pteridologists are also divided in their views regarding the generic status of Ceterachopsis with 5 well-defined species in Yunnan and the East Himalayas. We preferto mintain it as a genus separate from Asplenium on account of its distinct morphological features. It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way. 相似文献
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报道中国海产刚毛藻科(Cladophoraceae),沙生刚毛藻Cladophora arenaria,蝾螺刚毛藻C. conchopheria,暗色刚毛藻C. opaca,透明刚毛藻C. pellucida,微小刚毛藻C. pusilla,棉形刚毛藻C. rudolphiana,光毛刚毛藻C. sericea,美丽刚毛藻C. speciosa。 相似文献
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从武夷山和张家界自然保护区发现三虫草新种,武夷山虫草Cordyceps wuyishanensis, 张家界虫草Cordyceps zhangjiajiensis和拟茂兰虫草Cordyceps maolanoides。武夷山虫草和其近缘种的主要区别是,可孕部分柱状、非多年生、子囊孢子不断裂和间细胞长达6～10祄。张家界虫草与其近缘种相比较的鉴别特征为非木质化的较小子座、子囊壳表生和具有较长的(15～23祄)次生子囊孢子。拟茂兰虫草和近缘种茂兰虫草C.maolanoides的形态特征相近,其主要差别是前者的子座和子囊壳都小得多。报道了玫烟色拟青霉Paecilomyces fumosoroseus与蜣螂虫草Cordyceps geotrupis 有密切关系。研究标本保存于贵州大学真菌资源研究室(LFRGU)。 相似文献
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Recent research on relationships between diatoms and pH suggests that the genus Cyclotella exhibits a strong relationship with lake acidity, being almost totally absent below pH 5.5. This decline has been used as an indicator of lake acidification in paleolimnological studies. In this study C. stelligera V.H. and C. kützingiana Thwaites were abundant in Precambrian Shield lakes with pH as low as 4.5. Cyclotella comta (Ehr.) Kütz. was found in lakes of pH < 5.5, but maximum abundance was observed in lakes of pH > 5.5. Cyclotella michiganiana Skv. was found in lakes of pH < 6.0. These results indicate that the use of C. stelligera, C. kützingiana, and possibly C. comta, in paleolimnological investigations of lake acidification, should be approached with caution. These taxa may exhibit a decline in abundance with decreasing lakewater pH, but this is partially a morphometric effect not necessarily related to anthropogenic acidification. 相似文献
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从武夷山和张家界自然保护区发现三虫草新种,武夷山虫草Cordycepswuyishanensis, 张家界虫草Cordyceps zhangjiajiensis 和拟茂兰虫草Cordycepsmaolanoides.武夷山虫草和其近缘种的主要区别是,可孕部分柱状、非多年生、子囊孢子不断裂和间细胞长达6～10μm.张家界虫草与其近缘种相比较的鉴别特征为非木质化的较小子座、子囊壳表生和具有较长的(15～23μm)次生子囊孢子.拟茂兰虫草和近缘种茂兰虫草C.maolanoides的形态特征相近,其主要差别是前者的子座和子囊壳都小得多.报道了玫烟色拟青霉Paecilomycesfumosoroseus与蜣螂虫草Cordyceps geotrupis 有密切关系.研究标本保存于贵州大学真菌资源研究室(LFRGU). 相似文献
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Quantitative cytological and fatty acid composition was determined for the diatom Cyclotella meneghiniana Kütz, Data from four separate experiments were examined to elucidate changes that may occur with respect to daily photoperiod. Overall, fatty acid composition is similar to that reported for other diatoms with the exception that the C16 fatty acids constitute approximately 70% of all fatty acids. The major fatty acids are C14:0, 16:1, 16:0, 18:0, and 20:5. Fatty acids that are present in minor amounts are iso-14:0, iso-15:0, 15:0, 17:0, 18:4, 18:2, 18:1, 19:0, 20:0, 22:0, and 23:0. Cytological composition is similar to that previously reported with the chloroplast and vacuole being the largest compartments within the cell. Changes in both cytological and fatty acid composition were studied with respect to the light / dark cycle. Chloroplast and lipid relative volume are greatest during the early part of the dark period. Nuclear relative volume is lowest in the dark and increases throughout the light period. Total unsaturated fatty acids, including the C20:5 fatty acid, are lowest in the early part of the light period and highest in the dark. The sum of the C16 fatty acids remains constant at 70% of total fatty acids in the cells throughout the light/dark cycle, although percent composition of these two fatty acids shifts. The data suggest that cyclical changes occur in both quantitative morphology and fatty acids composition with respect to daily photoperiod. The cells, although not rigidly synchronized, most likely divide in the latter part of the dark period or in the first hours of the light period. Lipids increase dramatically in the dark. The ecological implications of lipid storage are discussed in relation to lipophilic toxicants. 相似文献
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浙江桂、普陀桂和日本桂(天竺桂)是樟属植物中的三个相近种。六十多年以来,围绕着它们的亲缘关系及其分类等级,植物学界展开了反复的讨论,至今仍然存在着较大的分歧。在文献考证的基础上,笔者通过赴模式产地考察与采集鉴定,从比较形态学、扫描电镜观察、种子油脂成份的化学分析和地理分布区等方面,进一步研究了这三个种的异同,认为浙江桂是中国大陆的特有种;普陀桂应当归并入日本桂,作为一个变种处理;日本桂的原变种在中国仅见产于台湾省,而在大陆并无自然分布。 相似文献
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Candido Regina Celia Toloi Maria Regina Torqueti Franceschini Silvio Antonio Garcia Flaviane Ramos Minto Elaine Cristina Manini 《Mycopathologia》1998,144(1):15-20
Vaginal candidiasis continues to be a common cause of vaginal discharge, pruritus and other local complaints in women worldwide. Although numerous antimycotic agents are available for the treatment of yeast vaginitis there is little comparative data on the in vitro activity of these drugs. The objectives of this study were to isolate and identify the Candida species in the vagina and anus of patients treated in a gynaecology clinic, as well as determine the susceptibility to azolic compounds measured by the E-test method. Vaginal and rectal swabs were collected from 80 adult non-pregnant patients, seen at a gynaecological clinic, aged 18–59 years, with sexual activity, with and without vaginitis. The swabs were processed by methods routinely used for the detection of pathogenic yeasts. The susceptibility of the isolates to fluconazole, ketoconazole and itraconazole, was measured by the agar diffusion method (E-test), using RPMI 1640 medium with 2% glucose and phosphate buffer. Candida species (33) strains were isolated from 17 patients at similar proportions from both anatomical sites, and 12 patients harboured 24 strains of C. albicans in the vaginal and rectal tracts. Twenty one percent of the strains of C. albicans were resistant to ketoconazole, 54% were resistant to itraconazole and 0% were resistant to fluconazole. The sensitivity of strains isolated from the two sites were similar, indicating that these are strains of the same phenotype. This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Chen Sing-Chi 《植物分类学报：英文版》1985,23(5):369-375
In addition to describing a new species, Cypripedium wumengense, as wellas a new variety, C. bardolphianum var. zhongdianense, nomenclatural and taxonomicnotes are made on its allies and the division to which they belong. They are ltrge]yfound in the Hengduan Mountains in southwestern China, characterized by the absenceof bract, havirg lip more or less covered with small wart-like outgrowths, and that asthe capsule matures the scape becomes much elongated. Six species of this group havehitherto been reported, of which, however, C. ebracteatum and C. nutans are regardedhere as conspecific with C. fargesii and C. bardolphianum respectively. Thus, includingthe new taxa described here, it composes five species and one variety: C. bardolphianumW. W. Sm. et Farrer (var. bardolphianum and var. zhongdianense S. C. Chen), C. micranthum Franch., C. fargesii Franch., C. margaritaceum Franch. and C. wumengenseS. C. Chen. They are all grouped here into the same section, Sect. Trigonopedium(Franch.) Pfitz., the oldest legitimate name of this group in the rank of section. 相似文献
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