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1.
The studies were made with stationary cultures of Anabaena cylindrica (blue-green alga). The bacterial microflora accompanying blue-green algae is subject to succession and elimination in the course of growth. The bacteria are able to utilize organic products released by the blue-green algae. The products released by A. cylindrica to the environment are peptide-like compounds.  相似文献   

2.
The Comparative Boron Nutrition of Several Green and Blue-Green Algae   总被引:1,自引:0,他引:1  
The boron requirements of filamentous and non-filamentous species of green and blue-green algae have been investigated. A primary feature of this study was the quantitative analysis of the cells for boron. This permitted expression of the degree of purification of the environment and the boron requirements of the organisms in terms of cell content. Three species of green algae were shown neither to require boron nor to absorb it in appreciable amounts. In contrast, three species of blue-green algae readily absorbed boron and nitrogen fixing species showed a marked growth response to boron when nitrate was omitted from the culture medium. The response to boron was less with nitrate in the medium, probably due to increased contamination from the nitrate salt rather than an involvement of boron in the fixation process. The boron content of the deficient blue-green algae was 1–2 μg/g, suggesting a requirement below dicot angiosperms and comparable to monocots. In agreement with other reports, the fungus Penicillium chrysogenum neither required nor absorbed boron.  相似文献   

3.
Blooms of blue-green algae from 51 eutrophic Scandinavian lakes were investigated during the period 1978–1984, to ascertain the occurrence of toxinogenic species. Toxicity assays were performed by intraperitoneal injection of suspensions of freeze-dried algal material in mice. Toxin-producing blue-green algae were found in 30 lakes. They belonged to 11 different species of the six genera Anabaena, Aphanizomenon, Gomphosphaeria, Microcystis, Nodularia and Oscillatoria. The presence of toxinogenic strains of blue-green algae seemed quite constant in several of the localities studied. In some lakes, more than one toxic species were found to develop simultaneously. The level of toxicity showed large variation (MLD100, 6 to > 2500 mg/kg), but clinical and pathological changes were quite uniform. The results indicate that water-blooms of toxin-producing blue-green algae, in the geographical area in question, are regionally widespread. In some localities, blooms of blue-green algae are apparently always toxic. Several aspects of the toxic blue-green algae problem are discussed.  相似文献   

4.
对蓝藻“红圈病”的病症、发病条件、传播程度方式、危害进行了研究。结果表明,发病条件与蓝藻最佳生长条件基本一致;病原通过水体和带病藻体传播,对藻的产量和质量均造成严重危害。同时探讨了综合防治措施。  相似文献   

5.
Summary a)Nitrogen fixation in rice fields. Nitrogen-fixing blue-green algae grow abundantly in tropical regions and are particularly common in paddy fields. Their possible role in the nitrogen accumulation of soil has been studied. The most vigorous nitrogen-fixing blue-green algae have been assessed for use as green manure in rice fields and favorable effects have been reported in India and other countries. b)Nitrogen fixation by algae in water. The planktonic blue-green algae occur abundantly at certain time of the year in sea water and lake water, and some of them are known to be nitrogen fixers. Certain Japanese species of blue-green algae can withstand high temperatures including ten nitrogen-fixing species from hot-spring waters. c)Nitrogen fixation by symbiotic blue-green algae. Certain species of blue-green algae form associations with other organisms such as fungi, liverworts, ferns and seed plants. The relationship between these two organisms is on one occasion commensal and on others symbiotic. Certain symbiotic blue-green algae are provided with the ability to fix the atmospheric nitrogen.  相似文献   

6.
The Waikato River (latitude 38°S, longitude 176°E, North Island, New Zealand) is overwhelming y dominated by diatoms (mainly Melosira species) while blue-green and green algae are of minor importance. Both laboratory and in situ nutrient enrichment experiments showed enhanced growth of natural and index blue-green and green algae by addition of phosphate and nitrate. These algae were also shown to require higher temperature and light intensity than the diatoms. On the other hand, Waikato River with its higher silica content, moderate range of temperature and running water habitat was more favourable an environment for diatoms.  相似文献   

7.
太湖蓝藻滤液的遗传毒性研究   总被引:1,自引:0,他引:1  
蓝藻爆发是环境污染引发的重要事件之一,随之产生的蓝藻毒素又直接危及区域水安全.该论文采用蚕豆和大蒜根尖微核试验研究了太湖蓝藻暴发期间蓝藻滤液的遗传毒性.结果表明,同阴性对照相比,所有试验处理对蚕豆根尖细胞微核发生率的影响显著增加;对大蒜根尖细胞微核发生率而言除蓝藻滤液8倍稀释液的影响不显著外,其它水平效应显著高于阴性对照,而且表现出一定的剂量效应.暴发期蓝藻滤液原液对蚕豆根尖细胞微核发生率影响显著高于阳性对照(0.8mg·mL-1环磷酰胺)的效应,从而说明蓝藻暴发时期蓝藻滤液具有较强的遗传毒性.通过微核试验效果分析,蚕豆作为植物监测系统的敏感性和稳定性都优于大蒜材料.  相似文献   

8.
Studies with deoxyribonucleic acid from blue-green algae   总被引:9,自引:0,他引:9  
Summary The total DNA in species of blue-green algae is similar to that of bacteria on an individual cell, but not on a dry weight, basis. The % G+C content of DNA from four species of blue-green algae has been determined by melting temperature measurement. An attempt tomeasure genetic homology between blue-green algae and certain bacterial species is described.  相似文献   

9.
Electron microscopic studies of Sphagnum lindbergii (Schimp.) and S. riparium (Ångstr.) have revealed the presence of intracellular organisms such as blue-green algae, green algae, bacteria and fungi. Nitrogenase activities of these Sphagnum mosses were found to be related mainly to the presence of intracellular Nostoc filaments. The appearance of nitrogen-fixing blue-green algae within bryophytes is thus not restricted to liverworts. The association is likely to be of ecological importance as it seems to occur in very acid habitats generally lacking blue-green algae. Possible interrelations between the moss, the blue-green algae and different types of bacteria are discussed.  相似文献   

10.
Pyridine nucleotide-dependent glucose dehydrogenase activity (GPND) is described for the first time in cell-free extracts of certain blue-green algae. When glucose is added to these crude cell extracts, nicotinamide adenine dinucleotide phosphate is reduced at twice the rate as nicotinamide adenine dinucleotide; but evidence suggests that this activity is due to a single enzyme. The distribution and level of GPND in selected blue-green algae correlates with the heterotrophic potential of each species. In all blue-green algae where GPND was detected, O(2) uptake coupled to the GPND reaction was also observed. Both GPND and O(2) uptake apparently occur in the soluble fraction of the cell. An essential role for GPND in the heterotrophic metabolism of blue-green algae is postulated.  相似文献   

11.
The reflection spectra of subaerial blue-green algae (Cyanophyceae) lack the reflected high peak of the reflected infrared spectral wave band (770--1000 nm)as usually exists in green seed plants. The curve of reflected ratio slopes gently. The reflected ratio of bluegreen algae growing on the mineral soil was positively correlated with the Mo concentration in the cells, and was evidently greater than that of the normal soil blue-green algae (13 %-- 27 %). This abnormal reflection ratio was related to the mineral concentration in soil. The reflection spectra of green algae (Chlorophyceae) and bryophyta were similar to these of the subaerial blue-green algae.  相似文献   

12.
Marine blue-green algae, Lyngbya Lagerheimii, Microcoleus chthonoplastes, Plectonema terebrans, Agmenellum quadruplicatum, and freshwater blue-green algae, Anacystis nidulans, Anabaena variabilis, Nostoc muscorura, and Oscillatoria sp. treated with lysozyme (muramidase) formed spheroplasts but not protoplasts. The time needed for spheroplast induction varied with the species. Approximate internal osmotic pressures of the blue-green algae were determined. Marine algae generally had a higher osmotic pressure than freshwater algae.  相似文献   

13.
Grazing on filamentous algae by herbivorous zooplankton   总被引:8,自引:0,他引:8  
SUMMARY. 1. Feeding experiments were conducted to examine filtering rates and selectivity of a variety of zooplankton taxa (including cladocerans, copepods and a rotifer) for filamentous diatoms, green and blue-green algae.
2. Most herbivores were capable of consuming some filamentous algae at rates similar to or higher than those on unicellular algae. Only feeding of Diaphanosoma brachyurum Liéven and Moina micrura Kurz seemed to be primarily limited by the filamentous morphology.
3. Filtering rates and selectivities of most herbivores were much higher for the diatom Melosira granulata angustissima Müller than for similarly sized blue-green algal filaments, indicating that chemical factors strongly influence consumption of filamentous algae.
4. The toxic blue-green algal filament Anabaena flos-aquae De Brébisson NRC 44–1 had a much strong inhibitory effect on zooplankton feeding than other filaments. The only herbivores that were not inhibited by this strain have been shown to be resistant to blue-green algal toxins, or strongly avoided consuming the blue-green alga. These results indicate that the inhibitory effect of filamentous algae is due more to toxic or noxious chemicals than to the filamentous morphology.
5. Selectivities of zooplankton for filamentous algae were largely independent of herbivore body size. The small-bodied cladoceran Bosmina longirostris Müller had the highest selectivities for filamentous algae.  相似文献   

14.
J C Landgraf  M J Starzyk 《Microbios》1978,18(73-74):151-157
A study was undertaken to determine the effects of passage through the cooling system of the Zion Nuclear Plant, Illinois, U.S.A., on the blue-green algae present in lake water. The blue-green algae were isolated by means of membrane filtration, enumerated and identified to genera. As a result of cooling system passage there was a definite reduction in the numbers of blue-green algae. This reduction appeared to be due to mechanical, as well as elevated temperature, damage. A few genera showed only a slight change in number.  相似文献   

15.
巨大螺旋藻光合放氧和超微结构的研究   总被引:4,自引:0,他引:4  
选用常温下培养的巨大螺旋藻为材料,对其光合放氧与超微结构进行了观察和研究。结果表明:1)巨大螺旋藻具有较强的放氧能力;2)巨大螺旋藻细胞内存在有含量极丰富的类囊体,气泡,藻胆体及羧化体等特写结构与其光合放氧特性相适应;3)类囊体膜片层在细胞的部分区域已趋于重叠,且封闭成一独立系统存在,具类似真核生物叶绿体的结构;4)从进化角度来看,巨大螺旋藻类囊体膜存在的方式可以作为叶绿体系统演化的证据之一,即真  相似文献   

16.
Summary All of the three blue-green algae, Anabaena cylindrica, Mastigocladus laminosus and Nostoc muscorum are characterized by the presence of multi-layered envelopes (sheath, wall and plasma membrane), photosynthetic lamellae and a variety of intracellular granules. Sections of heterocysts of Anabaena cylindrica showed the presence of an internal membrane system as well as lamellae. An unusual feature of the structure of Nostoc muscorum was the presence of densely stained intracellular membranes or lamellae. The results emphasize the variability in appearance of the internal structure of the blue-green algae and point to the need for detailed investigations of the influence of change in physiological environment on the anatomy of these organisms.  相似文献   

17.
柴达木盆地荒漠土壤蓝藻群落的初步研究   总被引:6,自引:0,他引:6  
本文分析了柴达木盆地东部和中部具有代表性地区的丘陵、戈壁和沙丘的蓝藻种类组成、生物量及主要的土壤化学成分;采用了模糊聚类、系统聚类及多元线性回归等方法分析藻类的群落及其与环境因子的关系。共鉴定出21种蓝藻,其中6种为国内首次报道。研究表明:土壤含磷量、总盐量及与粘性和湿度有关的土壤结构是决定柴达木盆地蓝藻群落组成的重要因素。  相似文献   

18.
SUMMARY. 1 Total fluorescence spectra of thirty-two freshwater algae show that the majority of the information is contained in the excitation spectrum of emission at 680 nm.
2. Previously suggested characteristics for the automatic identification of blue-green algae from their fluorescence properties, i.e. the presence of high phycoerythrin fluorescence and low chlorophyll fluorescence, are shown to be inapplicable to the freshwater blue-green algae studied here.  相似文献   

19.
The amino acid sequence of ferredoxin from Synechocystis 6714, a unicellular blue-green alga, was determined by a combination of conventional methods. The ferredoxin was composed of 96 amino acid residues and lacked methionine and tryptophan. The sequence was as follows: Ala-Ser-Tyr-Thr-Val-Lys-Leu-Ile-Thr- Pro-Asp-Gly-Glu-Asn-Ser-Ile-Glu-Cys-Ser-Asp-Asp-Thr-Tyr-Ile-Leu-Asp-Ala-Ala- Glu-Glu-Ala-Gly-Leu-Asp-Leu-Pro-Tyr-Ser-Cys-Arg-Ala-Gly-Ala-Cys-Ser-Thr-Cys- Ala-Gly-Lys-Ile-Thr-Ala-Gly-Ser-Val-Asp-Gln-Ser-Asp-Gln-Ser-Phe-Leu-Asp-Asp- Asp-Gln-Ile-Glu-Ala-Gly-Tyr-Val-Leu-Thr-Cys-Val-Ala-Tyr-Pro-Thr-Ser-Asp-Cys-Thr-Ile-Glu-Thr-His-Lys-Glu-Glu-Asp-Leu-Tyr. In an alignment of various ferredoxins with high homology from unicellular and filamentous blue-green algae, Synechocystis 6714 ferredoxin showed 4 gaps. Those between residues 9 and 10 and between residues 12 and 13 were unique for the ferredoxins from the unicellular algae Synechocystis 6714 and Aphanothece sacrum (ferredoxin I). Therefore, ferredoxins from unicellular algae were distinguishable from those of filamentous algae in terms of the presence of gaps. This feature appears to coincide with the phylogenetic division between the two types of blue-green algae.  相似文献   

20.
Heterotrophic Growth of Blue-Green Algae in Dim Light   总被引:7,自引:0,他引:7       下载免费PDF全文
A unicellular blue-green alga, Agmenellum quadruplicatum, and a filamentous blue-green alga, Lyngbya lagerheimíi, were grown heterotrophically in dim light with glucose as major source of carbon and possibly energy. The dim-light conditions did not support autotrophic growth. The two blue-green algae appeared to have the same metabolic block, namely an incomplete tricarboxylic acid cycle, as has been found in other obligately phototrophic blue-green algae. Under dim-light conditions, glucose made a greater contribution to cell constituents (amino acids) of A. quadruplicatum and L. lagerheimii than under high-light conditions.  相似文献   

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