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1.
Based on the sequence data of the nuclear ribosomal DNA internal transcribed spacer(ITS) 1,5.8 S,and ITS 2,the molecular phylogeny was analyzed on Ulvaceae species collected from Qingdao coasts in summer of 2007,including 15 attached Ulva and Enteromorpha samples from 10 locations and 10 free-floating Enteromorpha samples from seven locations.The result supported the monophyly of all free-floating Enteromorpha samples,implying the unialgal composition of the free-floating Enteromorpha,and the attached Ulvaceae species from Qingdao coasts were grouped into other five clades,suggesting that they were not the biogeographic origin of the free-floating Enteromorpha in that season.  相似文献   

2.
Green tides are caused by the proliferation of chlorophytes under suitable hydrographic conditions.These blooms lead to environmental degradation and negatively impact the waters and seagrass beds,as well as fishing and other recreational activities in the bay.A comprehensive ecological understanding of the bloom dynamics,including the origin and persistence,is needed to foster management decisions.The algae in the great majority of green tide blooms usually belong to two genera of Ulvophyceae,Ulva and Enteromorpha.Ulva has been observed more often in recent years.In China,green tides occurred for the first time in the middle area of the Yellow Sea in 2007,and a large-scale algae blooming broke out in the middle and southern areas of the Yellow Sea in late May 2008.We identified them as Ulva prolifera by comparative analysis of the rDNA internal transcribed spacer 1 (ITS1),5.8S and ITS2 sequences in combination with microscopic observation.Morphological differences were found between the free-floating algae and the attached thalli.Various reproduction patterns of the free-floating algae include sexual,asexual and vegetative propagations,which played important roles in the long-term green tide persistence in China.The ITS sequences of the blooming algae were identical to those of the samples from the Lianyungang sea area but were different from the attached samples from the Qingdao sea area.The results infer that the blooms are originated from other sea areas rather than from the local attached populations.  相似文献   

3.
Ulvacean green seaweeds are common worldwide; they formed massive green tides in the Yellow Sea in recent years, which caused marine ecological problems as well as a social issue. We investigated two major genera of the Ulvaceae, Ulva and Enteromorpha, and collected the plastid rbcL and nuclear ITS sequences of specimens of the genera in two sides of the Yellow Sea and analyzed them. Phylogenetic trees of rbcL data show the occurrence of five species of Enteromorpha (E. compressa, E. flexuosa, E. intestinalis, E. linza and E. prolifera) and three species of Ulva (U. pertusa, U. rigida and U. ohnoi). However, we found U. ohnoi, which is known as a subtropical to tropical species, at two sites on Jeju Island, Korea. Four ribotypes in partial sequences of 5.8S rDNA and ITS2 from E. compressa were also found. Ribotype network analysis revealed that the common ribotype, occurring in China, Korea and Europe, is connected with ribotypes from Europe and China/Japan. Although samples of the same species were collected from both sides of the Yellow Sea, intraspecific genetic polymorphism of each species was low among samples collected worldwide.  相似文献   

4.
Results of neutron activation analysis (NAA) ofSargassum thumbergii samples collected from the Qingdao Taipingjiao coast on March 20, 1996 showed that (1)Sargassum thunbergii can to some extent accumulate potassium and calcium (the accumulation coefficient was 10); (2) it can accumulate almost all trace elements, especially iron, managanese and zinc; (3) it can accumulate strontium, aluminium thorium, and rare earth elements. Contribution No.3308 from the Institute of Oceanology, Chinese Academy of Sciences. The study supported by the National Ninth-Five-Year Key Project “96-916-04-01”.  相似文献   

5.
Competition among HAB (Harmful Algal Bloom) species Dinoflagellate Alexandrium tamarense, Raphidophyte Heterosigma carterae, and Diatom Skeletonema costatum was studied in the laboratory. Experiments with these three major HAB species under combinations of different salinities (10, 18, 25, 30, 35) and temperatures (19℃, 25℃) were carried out. The results showed that S. costatum successfully competed with the other two species at salinities of 18, 25,30, and 35 at temperatures of 19℃ and 25℃. However, H. carterae showed its advantage at low salinity of 10 and became the single dominant species at salinity 10 and 25℃. A. tamarense could not compete successfully with the other two species especially at low salinities. However, it could remain at low density in the presence of higher densities of other algae.  相似文献   

6.
Two new species of the genusTinocladia Kylin (1940)T. eudesmoides Ding et Lu sp. nov. andTinocladia zhangii Ding et Lu sp. nov., are described.T. eudesmoides is mainly characterized by its longitudinally and transversely produced sub-cortical filaments from the medulla, its short uniseriate assimilating filaments, usually composed of 6–10 cells with slightly swollen and narrow ultimate cells, and its unilocular sporangia (60–115)×55–70μm, variable in size.T. zhangii is mainly characterized by its very solid frond, not rip apart by hands, its evident longer primary branches, its short and slender secondary branches, with very evident sub-cortical layer, and filaments divided repeatedly, and its large and small unilocular sporangia, with the latter borne on an evidently swollen pedicel. Project B80981816 supported by the NSFC. Contribution No. 4443 from the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

7.
Two new species of the genus Tinocladia Kylin, T. gracilis sp. nov. and T. microsporangii sp. nov,, are described. T. gracilis is characterized by its slender frond, variable size, infrequently branched medullary filaments, and short assimilating filaments with 2 - 7 cells. T. microsporangii is characterized by its medullary cells which are slightly larger than sub-cortical ones; narrow sub-cortical layer, usually consisting of 4- 6 cells and very small unilocular sporangia. The holotypes are deposited at the Herbarium of the Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China.  相似文献   

8.
The 5.8S ribosomal DNA sequences (5.8S rDNA) and their flanking regions, internal transcribed spacer 1 and spacer 2 (ITS1 and ITS2) of three new isolates in genus Alexandrium (Alexandrium sp. qd1, Alexandrium sp. qd2, Alexandrium sp. gz) from China were amplified, sequenced, and subjected to phylogenetic analysis. Alexandrium sp. gz and Alexandrium sp. qd1 were grouped with high bootstrap values with four strains/species, i.e., A. catenella South Korea strain, A. catenella Japan strain, and two from China, Alexandrium sp. AC03 and Alexandrium sp. AN01 being proposed to be A. catenalla in a previous study. Then Alexandrium sp. gz and Alexandrium sp. qd1 were identified as Alexandrium catenella. As A. catenella was isolated from Qingdao and Guangzhou sea areas, it supposedly distributed at least in these two areas and was genetically different. Alexandrium sp. qd2 differed greatly from species in Alexandrium. It clustered with Symbiodinium californium, Symbiodinium sp. G15 and Gymnodinium sp. Zhao 01 with 100% bootstrap value; so Alexandrium sp. qd2 affiliates to genus Symbiodinium, and is probably a free-living Symbiodinium species.  相似文献   

9.
Unicellular gametophytes ofUndaria pinnatifida (Harv.) Sur. were isolated in Qingdao, P. R. China in April 1993 and in Tokushima, southern Japan in March 1995. Different intraspecific crossings by using unicellular male and female gametophytes were successfully undertaken in Sept. of 1995 in Qingdao. Sporophytes were transplanted to two different locations for open sea cultivation. One was at Zhanqiao (ZQ) Bay where the water current was slower than that of another location—Taipingjiao(TPJ). A total of 218 adult sporophytes were harvested on January 12 and 18 from TPJ and ZQ respectively. For eacn combination, 10 sporophytes were cultivated. Analysis of the morphological characteristics of adult sporophytes indicated that the longest length between two bases of the serration of pinnate blades (W2) is a morphological characteristic that can be transferred from the parent plant to the next generations regardless of environmental variations. There was evidence that W2 was apparently determined by sex-linked factors, i.e., by male parental gametophyte. Sporophytes from certain crossing combinations showed more vigorous growth than those from other crossing combinations. It is therefore possible to select gametophyte strains which can be used as parental gametophytes for the seedling production of sporophytes with more vigorous growth within shorter cultivation period. The morphology of hybrids from a Qingdao strain and a Tokushima cultivated strain resembled that of both parental plants in frond features (wrinkled or smooth) and W2. Sporophyll formation also varied with strains. The fact that adult sporophytes resulting from the same crossing combinations have identical morphological characteristics under the same environmental conditions indicates the possibility of a new way to select strains which are expected to be ideal for commerical production by purposely selecting, propagating, and seeding unicellular gametophytes for sporeling production through freeliving techniques of gametophytes. Project 39400102 supported by NSFC, also supported by National Climbing Plan B (PD-B642); and Bioengineering Center, SSTC.  相似文献   

10.
We examined the effects of polypeptide fromChlamys farreri (PCF) on the amount of hydroxyproline in guinea pig skin irradiated by chronic ultraviolet A (UVA) and ultraviolet B (UVB) radiation. PCF was applied locally before repeated exposure of guinea pig to UVA and UVB. The contents of hydroxyproline and other amino acids in guinea pig skin were determined by automatic amino acid analyzer. Our results showed that: (1) long-time UVA and UVB radiation can reduce dramatically the amounts of hydroxyproline, aspartic acid, threonine, glycine, phenylalanine and lysine in guinea pig skin in comparison with the control group (P<0.05); (2) Compared with model group, pre-treatment with 5% and 20% PCF prior to UVA and UVB radiation can inhibit the decline of amino acids content in guinea pig skin in a dose-dependent manner (P<0.05). As the decrease of hydroxyproline, glycine and lysine contents in the skin directly reflexes type I collagen degeneration, our results indicated that the chronic application of PCF can protect skin type I collagen against UV radiation, and thus protect skin from photoaging. Project No. 39970638 supported by the NSFC, and also supported by the Science and Technology Bureau of Qingdao (No: 2001-28-50).  相似文献   

11.
The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure line was cloned and sequenced. Sequence analysis was executed for this sequence and other 22 sequences retrieved from GenBank. A phylogenetic tree was constructed using the neighbor-joining method. The results revealed a high diversity of 18S rDNA sequences in genus Porphyra and the considerable variation of 18S rDNA sequences in different strains of the same species P. yezoensis and P. tenera. Significant difference of 18S rDNA sequence was observed between P. yezoensis from Qingdao, China, and the two strains of P. yezoensis from Japan, but the three strains of P. yezoensis formed a stable clade in the phylogenetic tree. These results indicate the possibility of interspecies and intraspecies discrimination of Porphyra using the 18S rDNA sequences.  相似文献   

12.
The hybrid between olive flounder Paralichthys olivaceus and stone flounder Kareius bicoloratus was produced by artificial insemination of olive flounder eggs with stone flounder sperm. Sinistral and dextral are two types of hybrid progeny after metamorphosis. Karyotypes of both hybrid flounders are the same as those of the two parental species. Of the 22 loci examined from 12 allozymes, 12 confirmed hybridization of the paternal and maternal loci in hybrids and no difference was found in allozyme patterns of sinistral and dextral hybrid fishes. RAPD patterns of these specimens were also studied with 38 primers selected from 104 tested. Among them, the PCR products of 30 primers showed hybridization of the paternal and maternal bands. Genetic variation between hybrids and their parental stocks was analyzed by RAPD using 10 of the above 38 primers. The average heterozygosity and genetic distance were calculated. The results suggested that the filial generation could inherit a little more genetic materials from paternal fish than that from maternal fish. Supported by National Natural Science Foundation of China (No. 30571445), National High-Technology Research and Development Program (863 Program, No. 2006AA10A404), and Project from the Ministry of Science and Technology of China (No. 2006DKA30470-017)  相似文献   

13.
Synedra ulna var, repanda Q. X. Wang & Q. M. You, a new variety of Synedra (Bacillariophyta) from Xinjiang, China, is described and illustrated, and the characteristic of the variety: includes undulate-linear valves and straight pseudoraphe, differs from other species of Synedra.  相似文献   

14.
Sodium thiosulphate and neutron activation determination of iodine content in samples of 18Sargassum species collected in Guangdong and Guangxi Province in April 1996 showed large differences (0.47×10−3 inSargassum hemiphyllum, 0.56×10−3 inSargassum assimile, and 4.5×10−3 inSargassum vachellianum). Traditional titration analysis and neutron activation analysis for determination of total iodine yielded similar results showing that certainSargassum species had high capacity to accumulate iodine. Contribution No. 3162 from the Institute of Oceanology, Chinese Academy of Sciences. The project was supported by the National Ninth Five-Year Plan of China (No. 96-916-04-01).  相似文献   

15.
A full length amphioxus cDNA, encoding a novel phosducin-like protein (Amphi-PhLP), was identified for the first time from the gut cDNA library of Branchiostoma belcheri. It is comprised of 1 550 bp and an open reading frame (ORF) of 241 amino acids, with a predicted molecular mass of approximately 28 kDa. In situ hybridization histochemistry revealed a tissue-specific expression pattern of Amphi-PhLP with the high levels in the ovary, and at a lower level in the hind gut and testis, hepatic caecum, gill, endostyle, and epipharyngeal groove, while it was absent in the muscle, neural tube and notochord. In the Chinese Hamster Ovary (CHO) cells transfected with the expression plasmid pEGFP-N1/Amphi-PhLP, the fusion protein was targeted in the cytoplasm of CHO cells, suggesting that Amphi-PhLP is a cytosolic protein. This work may provide a framework for further understanding of the physiological function of Amphi-PhLP in B. belcheri. Supported by the Pilot Projects of Knowledge Innovation Project of Chinese Academy of Sciences (No. KZCX2-YW-211-03 and MGE2008KG06)  相似文献   

16.
We collected nine Enteromorpha specimens from the coast of Yantai and evaluated their diversity based on analyses of their ITS (internal transcribed spacer) and 5S rDNA NTS (non-transcribed spacer) sequences. The ITS sequences showed slight nucleotide divergences between Enteromorpha linza and Enteromorpha prolifera. In contrast, multiple highly variable regions were found in the ITS region of Enteromorpha flexuosa. In general, there were more variable sites in the NTS region than in the ITS region in the three species. The variations in 5S rDNA NTS sequences indicated that the molecular diversity of Enteromorpha from the coast of Yantai is very high. However, a phylogenetic tree constructed using 5S rDNA NTS sequence data indicated that genetic differences were not directly related to geographical distribution.  相似文献   

17.
The ultrastructure of hemocytes ofPenaeus vannamei was examined by transmission electron microscope. Three types of hemocytes were identified: hyaline cell, small-granule cell and large-granule cell. Hyaline cells are the smallest of the hemocytes, lack electron-dense granules, have average size of 11.11 μm (SE±0.50,n=10)×6.96μm (SE±0.55,n=10), comprise 25.8% (SE±2.87,n=4×10) of the hemocytes; small granule cells are the most abundant type of hemocytes, comprise 58.1% (SE±3.40,n=4×10) of the hemocytes, contain small electron—dense granules, have average size of 10.78 μm (SE±0.60,n=10)×8.63 μm (SE±0.44,n=10); and large-granule cells comprise 16.1% (SE±2.55,n=4×10) of the hemocytes, are filled with large electron dense granules, have average size of 12.51 μm (SE±0.63,n=10)×8.99μm (SE±0.71,n=10). This research was supported by the National Climbing Project B, PDB6-6-3. Contribution No. 3448 from the Institute of Oceanology, Chinese Academy of Sciences.  相似文献   

18.
AmpLifications with 300 10-base primers under predetermined optimal reaction yielded 2762 reproducible amplified fragments ranging from 200 to 3000 bp. Genetic distances among five species of Takifugu and Lagocephalus spadiceus as outgreup were calculated based on the presence/absence of the amplified fragments. Topological phylogenie trees of the 5 species of Takgfugu and the outgroup were gen-erated by Parsimony and Neighbor-Joining analysis based on RAPD data set. The genetic distance between T. rubripes and T. pseudommus was almost the same as that between individuals within each species, but was much smaller than that among T. rubripes, T. pseudommus and the other species. The molecu-lar data from RAPD analysis convincingly showed that T. rubripes and T. pseudommus should be the same species.  相似文献   

19.
3-factor experiment was used to study the combined effects of temperature, irradiance and salinity on the growth of an HAB species diatomSkeletonema costatum (Grev.) Cleve. The results showed that temperature (12, 19, 25, 32 °C), irradiance (0.02, 0.08, 0.3, 1.6)×1016 quanta/(s·cm2)) and salinity (10, 18, 25, 30, 35) significantly influenced the growth of this species. There were interactive effects between any two of and among all three physical factors on the growth. In the experiment, the most optimal growth condition forS. costatum was temperature of 25°C, salinity of 18–35 and irradiance of 1.6×1016 quanta/(s·cm2). The results indicatedS. costatum could divide at higher rate and were more likely to bloom under high temperature and high illumination from spring to fall. It was able to distribute widely in ocean and estuary due to its adaptation to a wide range of salinities. This study was supported by the PREPP and National Key Basic Research Project (2001CB4097) NNSFC No. 39950001, 20177023, 49576301, 49906007 and KZCX2-206.  相似文献   

20.
Randomly amplified polymorphic DNA (RAPD) technique was applied to assess the genetic variations and phylogenetic relationships in 4 species ofPorphyra. The samples were collected from the coast of Canada, Vietnam, Zhoushan, Fujian and Qingdao in China. Amplifications with 20 primers were carried out under predetermined optimal reaction conditions (samples were first heated at 94°C for 5 min. and followed by 45 cycles of 1 min at 94°C, 1 min at 36°C, and 2 min at 72°C, then held at 72°C for 10 min). The amplified products were scored as present (1) or absent (0) for each DNA sample and an index of genetic similarity (F) was calculated by using Nei & Li’s matching coefficient method (1979). The value of (1−F) was used to quantify the genetic distances between species and construct a phylogenetic tree. The relationship indicated by the UPGMA and NJ cluster analysis on the values of the genetic distance is in good overall agreement with classical taxonomy. The obvious differences between natural and cultivated population ofP. haitanensi suggest that variation or hybridization with other species occurred during the culture. Contribution No. 100 from the Experimental Marine Biology Laboratory, IOCAS. Contribution No. 3289 from the Institute of Oceanology, Chinese Academy of Sciences. The research supported by the Foundation of the Chinese Academy of Sciences.  相似文献   

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