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1.
To investigate the genetic structures and differentiation of different wild populations of white croaker （Pennahia argentara）, horizontal starch gel electrophoresis was performed on 133 individuals collected from five different locations in China and Japan. The eleven enzyme systems revealed 15 loci, of which eleven were polymorphic. The percentage ofpolymorphic loci of white croaker populations varied from 6.67% to 53.3.3%; the mean observed and expected heterozygosity ranged from 0.0033 to 0.0133 and 0.0032 to 0.0191, respectively. The expected heterozygosity revealed a low genetic variability for white croaker in comparison with other marine fishes. The genetic distances between populations ranged from 0.00005 to 0.00026. A weak differentiation was observed within each clade and between clades; and no significant differences in gene frequencies among populations were observed in white croaker. Among the five populations, three Chinese populations showed more genetic diversity than that in Japanese populations. 相似文献
2.
D. maculates is a kind of specialized Schizothoracinae fish has been locally listed as a protected animal in Xinjiang Province,China. Ili River located in north of Tianshan Mountain and Tarim River located in north of Qinghai-Tibetan Plateau were two main distribution areas of this fish. To investigate the genetic diversity and genetic structure of D. maculates,four populations from Tarim River system and two populations from Ili River system were collected in this study. A 570-bp sequence of the control region was obtained for 105 specimens. Twenty-four haplotypes were detected from six populations,only Kunes River population and Kashi River population shared haplotypes with each other. For all the populations examined,the haplotype diversity(h) was 0.904 8±0.012 6,nucleotide diversity(π) was 0.027 9±0.013 9,and the average number of pairwise nucleotide differences(k) was 15.878 3±7.139 1. The analysis of molecular variance(AMOVA) showed that 86.31% of the total genetic variation was apportioned among populations,and the variation within sampled populations was 13.69%. Genetic differences among sampled populations were highly significant. F st statistical test indicated that all populations were significantly divergent from each other(P 0.01). The largest F st value was between Yurungkash River population and Muzat River population,while the smallest F st value was between Kunes River population and Kashi River population. NJ phylogenetic tree of D-loop haplotypes revealed two main clades. The neutrality test and mismatch distribution analysis suggested that the fish had went through a recent population expansion. The uplift of Tianshan Mountain and movement of Qinghai-Tibetan Plateau might contribute to the wide genetic divergence of D. maculates in northwest China. 相似文献
3.
Knowledge of population genetic structure plays an important role in fisheries management.In this research,In-ter-Simple-Sequence-Repeat(ISSR)markers were employed to evaluate the genetic structure of Japanese sardinella(Sardinella zun-asi)populations in the Northwest Pacific.Eighty seven individuals from 5 locations were screened using 4 highly polymorphic prim-ers.A total of 173 polymorphic loci were detected out of 191 loci amplified.Small but significant genetic differentiation was de-tected between the Chinese and Japanese populations by both AMOVA and pairwise FST analyses,which was further supported by cluster analysis.We consider that climate change during glaciations should be responsible for the genetic differentiation.Isolation by geographic distance among populations was observed,indicating that the distance might also lead to the genetic differentiation.However,no genetic structure was found within the populations off both the Chinese and Japanese coasts,indicating a high-level along-coast gene flow,which might result from ocean current transport and common ground for over-wintering. 相似文献
4.
The genetic diversity of wild and hatchery populations of half-smooth tongue sole Cynoglossus semilaevis, based on observation of amplified fragment length polymorphism (AFLP) was described. Two hundred individuals from four wild populations, Laizhou (LZ), Weihai (WH), Qingdao (QD), Rizhao (RZ), and one hatchery population, Mingbo (MB), were screened using eight different AFLP primer combinations. A total of 384 loci were screened in the five studied populations. 48.4%, 51.3%, 50.7%, 49.3% and 45.8% of these loci were polymorphic among the individuals tested in the LZ, WH, QD, RZ and MB populations, respectively. The number of polymorphic loci detected by single primer combinations ranged from 17 to 35. The average heterozygosity of the LZ, WH, QD, RZ and MB populations was 0.072, 0.093, 0.092, 0.090 and 0.063, respectively. The WH population showed the highest genetic diversity in terms of total number of AFLP bands, total number of polymorphic bands, average heterozygosity and percentage of low frequency (0-0.2) polymorphic loci among all the populations, while the LZ population was the lowest among the wild populations. Compared with the wild populations, the hatchery population showed a low genetic viability. 相似文献
5.
To investigate the genetic variation and population structure of Pacific herring in the Yellow Sea and the genetic differentiation between the Yellow Sea and the Sea of Japan,fragments of 479-bp mitochondrial DNA control region were sequenced for 110 individuals collected from three different periods in the Yellow Sea and one locality in the Sea of Japan.High haplotype diversity and moderate nucleotide diversity were observed in Pacific herring.AMOVA and exact test of population differentiation showed no significant genetic differentiations among the three populations of the Yellow Sea and suggested the populations can be treated as a single panmictic stock in the Yellow Sea.However,a large and significant genetic differentiation(WST50.11;P50.00) was detected between the populations in the Yellow Sea and the Sea of Japan.The high sea water temperature in the Tsushima Strait was thought a barrier to block the gene exchange between populations of the two sea areas.The neutrality tests and mismatch distribution indicated recent population expansion in Pacific herring. 相似文献
6.
Zhikong scallop （Chlamys farreri） is an important maricultured species in China. Many researches on this species, such as population genetics and QTL fine-mapping, need a large number of molecular markers. In this study, based on the ex- pressed sequence tags （EST）, a total of 300 putative single nucleotide polymorphisms （SNPs） were selected and validated using high resolution melting （HRM） technology with unlabeled probe. Of them, 101 （33.7%） were found to be polymorphic in 48 indi- viduals from 4 populations. Further evaluation with 48 individuals from Qingdao population showed that all the polymorphic loci had two alleles with the minor allele frequency ranged from 0.046 to 0.500. The observed and expected heterozygosities ranged from 0.000 to 0.925 and from 0.089 to 0.505, respectively. Fifteen loci deviated significantly from Hardy-Weinberg equilibrium and significant linkage disequilibrate was detected in one pair of markers. BLASTx gave significant hits for 72 of the 101 poly- morphic SNP- containing ESTs. Thirty four polymorphic SNP loci were predicted to be non-synonymous substitutions as they caused either the change of codons （33 SNPs） or pretermination of translation （1 SNP）. The markers developed can be used for the population studies and genetic improvement on Zhikong scallop. 相似文献
7.
A total of 160 barramundi's(Lates calcarifer Bloch,1790)sampled from four rivers(Tentulia,Balaswar,Bakkhali,and Andarmanik)along the southern coastal region of Bangladesh were investigated in terms of morphometric characters to reveal the intraspecific variation.Twenty-five morphometric measurements were extracted using the conventional method and subjected to multivariate analyses(i.e.,principal component analysis(PCA),discriminate function analysis(DFA),cluster analysis(CA))to distinguish individuals from different rivers.The result demonstrated that twenty-two out of 2 5 measurements was statistically significant(Univariate ANOVA)among all four populations.PCA analy sis of morphometric characters resulted in two principal components,PC I and PCII which accounted for 79.25%and 4.28%of the total data variance.PC I-PC Ⅱ plot explained 83.5 3%of total variance differentiated the population of L.calcarifer into two groups.Discriminate analysis correctly classified about 88.1%of the examined fish into the four areas.The UPGMA dendrogram showed that Bakkhali populations were the most morphologically different populations in comparison to other populations,while Andarmanik and Balaswar populations were very close to each other.The strong morphometric variation between Bakkhali and Tentulia,Andarmanik and Balaswar was observed in the present study,suggested the evidence of the separate stock population of barramundi in these locations,which might require distinct stock management strategies for resource sustainability in the waters of southern Bangladesh.However,if these findings are supported by further molecular markers and geometric morphometry,this would be a strong indication of different stocks of this population in the four rivers of southern Bangladesh. 相似文献
8.
Pholis fangi is an ecologically important fish species inhabiting Chinese coastal waters of Yellow Sea and Bohai Sea. To investigate the genetic diversity and population genetic structure of P. fangi, a fragment of 487 bp in the first hypervariable region(HVR-1) of the mitochondrial DNA(mt DNA) control region was sequenced for 181 individuals collected from Bohai Sea and Yellow Sea. A total of 18 polymorphic sites were detected, which defined 25 haplotypes. A moderate level of haplotype diversity(h = 0.7052) and a low level of nucleotide diversity(π = 0.0028) were detected. Both the phylogenetic tree and the haplotype network showed no significant genealogical structure difference among sampling locations. Pairwise FST comparison and hierarchical molecular variance analysis(AMOVA) revealed that no significant genetic structure difference existed throughout the investigated regions, suggesting a high gene exchange among different populations. The results of neutrality test and mismatch distribution analysis indicated that a late Pleistocene population expansion(38000–127000 years ago) happened. Seasonal schooling migration may contribute to the genetically homogeneous population structure of the species. 相似文献
9.
Japanese flounder is one of the most important commercial species in China; however, information on the genetic background of natural populations in China seas is scarce. The lack of genetic data has hampered fishery management and aquaculture development programs for this species. In the present study, we have analyzed the genetic diversity in natural populations of Japanese flounder sampled from the Yellow Sea (Qingdao population, QD) and East China Sea (Zhoushan population, ZS) using 10 polymorphic microsatellite loci and cytochrome c oxidase subunit I (COI) sequencing data. A total of 68 different alleles were observed over 10 microsatellite loci. The total number of alleles per locus ranged from 2 to 9, and the number of genotypes per locus ranged from 3 to 45. The observed heterozygosity and expected heterozygosity in QD were 0.733 and 0.779, respectively, and in ZS the heterozygosity values were 0.708 and 0.783, respectively. Significant departures from Hardy-Weinberg equilibrium were observed in 7 of the 10 microsatellite loci in each of the two populations. The COI sequencing analysis revealed 25 polymorphic sites and 15 haplotypes in the two populations. The haplotype diversity and nucleotide diversity in the QD population were 0.746±0.072 8 and 0.003 34±0.001 03 respectively, and in ZS population the genetic diversity values were 0.712±0.047 0 and 0.003 18±0.000 49, respectively. The microsatellite data (F_st =0.048 7, P<0.001) and mitochondrial DNA data (F_st =0.128, P<0.001) both revealed significant genetic differentiation between the two populations. The information on the genetic variation and differentiation in Japanese flounder obtained in this study could be used to set up suitable guidelines for the management and conservation of this species, as well as for managing artificial selection programs. In future studies, more geographically diverse stocks should be used to obtain a deeper understanding of the population structure of Japanese flounder in the China seas and adjacent regions. 相似文献
10.
《中国海洋大学学报(英文版)》2020,(3)
Sillago nigrofasciata, a small to moderate size nearshore species, is newly found along the eastern and southern coasts of China. The present study is carried out in order to analyze the population genetics of the S. nigrofasciata. The control region sequence of mitochondrial DNA revealing 73 haplotypes were obtained from 162 individuals collected at 8 locations along the coast of China. The whole S. nigrofasciata population along the coast of China showed a low nucleotide diversity(0.012) and a high population diversity(haplotype diversity)(0.943), and all the 8 local populations showed low nucleotide diversities(0.014 – 0.001), suggesting the protective measures are effective. The haplotypes of the 8 local populations were widely distributed in haplotype network diagram and neighbor-joining phylogenetic tree, while no branch associating with sampling locations was detected. Recent gene flow analysis showed asymmetric gene exchanges among local populations. The pairwise FST values and unweighted pair-group method with arithmetic mean(UPGMA) tree revealed a certain amount of genetic difference among local populations. Moreover, analysis of molecular variance(AMOVA) reflected genetic differences between hypothetical subdivision groups. Neutral test and mismatch distribution of pairwise nucleotide suggested S. nigrofasciata may have experienced recent population expansion events. The historical geographic events associating with ice age may be the main explanation to the heterogeneity among local populations with short geographic distances, and the homogeneity among local populations with long geographic distances. 相似文献
11.
This paper reports results of study on the contents of proteins, amino acids, polysaccharose and uronic acids in 30 species of macroalgae from Shicao, Heishijiao, Shimiao, and Xiaofujiazhuang in the vicinity of Dalian City, N.E.China. The results showed that the protein contents of the 30 algae from highest (112.55μg/ml) to the lowest (0.24 p.g/ml) was in the descending order of Dictyopteris ndalata, Gelidium vagum,Gymnogongrus japonican, Ectocarpus confervoides, Tinocladia crassa, Sargassum thunberii. In general, the protein content in red algae was higher than that in brown algae. The content of free ami no acids showed nosignificent differences from 7.44μg/ml-4.96μg/ml in all these algae, in the descending order of Gymnogongrusrus japonican, Sargassum confusum, Undoria pinnatifida, Laminaria japonica and Ectocarpus confervoides. The content of polysaccharose varied from 168.2 gg/ml-22.15 p.g/ml in the descending order of Symphyocladiaia tiuscula, Scytosiphon lomentarius, Desmarestia viridis., Tinocladia crassa, Gracilaria asiatica and Porphyra yezoensis. The content of uronic acids is from 196.24μg/ml-20.77μg/ml in the descending order of Ulva lactuca,Symphyoclaldia latiuscula, Scytosiphon lomentarius, Ceramimum kondoi, Gracilaria vemucosa and Porphyra yezoensis. The fatty acids in 30 species of algae belong to Rhodophyta, Chlorophyta and Phaeophyta. Most phaeophytes have many (4-12) types of fatty acids. 相似文献
12.
The Chinese shrimp Penaeus (Fenneropaeneus) chinensis is an important species in marine fishery and aquaculture in China. A female Chinese shrimp Penaeus (Fenneropaeneus) chinensis was captured from west coast of the Korean peninsula and mated with a “Yellow Sea No. 1” male to produce the first filial
generation (F1) 100 F2 full-sib progeny from brother-sister crosses between F1 families was used for the mapping study. A genetic linkage map of the Chinese shrimp was constructed, based on 354 markers,
including 300 amplified fragment length polymorphism (AFLP) markers, 42 microsatellite (SSR) markers, and 12 randomly amplified
polymorphism (RAPD) markers. Forty-seven linkage groups (LGs) were identified. The total map length was 4 580.5 cM, with an
average spacing of 11.3 cM, covering 75.8% of the estimated genome size. The construction of this genetic linkage map was
part of a genetic breeding program. This linkage map will contribute to the discovery of genes and quantitative trait loci
(QTLs) in Chinese shrimp. 相似文献
13.
Fenneropenaeus penicillatus (redtail shrimp) is an important marine commercial animal in China. Recently, its resources have been depleted rapidly as a result of, for example, over-exploitation and environmental degradation of spawning grounds. Therefore, we analyzed the genetic diversity and differentiation of nine wild populations of F. penicillatus of China (Ningde, Lianjiang, Putian, Xiamen, Quanzhou, Zhangpu, Dongshan, Nanao, and Shenzhen populations) by amplified fragment length polymorphism (AFLP) technology, to provide genetic information necessary for resource protection, rejuvenation, artificial breeding, and sustainable use of the resource. Eight AFLP primer pairs were used for amplification, and 508 bands were detected among the populations. The results show that the percentage of polymorphic loci (P) ranged from 41.34% to 63.58%; the Nei’s gene diversity (H) of the populations was 0.119 4-0.230 5; and Shannon’s Information Index (I) was 0.184 1-0.342 5. These genetic data indicate that the genetic diversity of F. penicillatus was high. The genetic differentiation coefficient (GST=0.216 2) and gene flow (Nm=1.812 4) show that there was a high level of genetic differentiation and a moderate level of gene flow among populations. More studies on the genetic differentiation mechanism of F. penicillatus along the south-eastern coast of China need to be conducted to find more effective scientific protection strategies for the conservation of F. penicillatus genetic resources. 相似文献
14.
On the basis of scaling analysis,this paper presents a frontal geostrophic dynamic system which canbe used to describe the dynamics of an isolated bottom eddy and shows that five possible dynamicsubregimes are included in the system.A particle-in-cell method is used to investigate the behavior of the eddy in the two dynamic subregimes,with 1)nonlinear effect(ε)relevant to the sloping bottom-inducedbeta effect(β_1)and 2)seamount-induced beta effect(β_2)dominant.In the dynamic subregime of β_1～ ε～10~(-2)and β_2=0,the eddy can keep as a whole for a long time and migrates for a long distance.Inthe dynamic subregime where the seamount-induced beta effect (β_2～10~(-1))is dominant,the seamounttraps the water particles,causing the eddy to break up into a discrete set of eddies moving around the seamount. 相似文献
15.
The amplified fragment length polymorphic DNA (AFLP) technique was adopted to estimate the population genetic polymorphism
among 30 sporophytes of Laminaria japonica collected from a cultivating farm in Rongcheng, China. Three methods were used for genomic DNA extraction from Laminaria japonica sporophyte and only the products obtained using the improved genomic DNA extraction kit method proved qualified for AFLP
analysis. The parameters of the method were optimized. Samples of forty milligrams and the cell lysis time of 120 min were
suggested to replace the parameters recommended by the manufacturer. Thirty individuals of Laminaria japonica from the same cultivating site were investigated using one pair of selective primers. A total of 21 loci were obtained and
17 of them were polymorphic. The mean percent age of polymorphic loci of this population was 80.95%. The Nei’s gene diversity
(H) within this population was 0.3028 and the average Shannon’s Information index (I) was 0.4498. A genetic distance matrix
among different individuals was constructed as well. Through this study, an applicable AFLP genetic analysis working system
for Laminaria japonica sporophyte was established. The results of this research also revealed a high level of genetic diversity within the studied
population. 相似文献
16.
Based on DNA extraction and optimization of random amplified reaction (RAPD) to the gametophytes and sporophytes of Kelp “901”
strain, genetic study on variation was conducted to its parents and offsprings of F6, F7, F8, and F9 generation. RAPD results have shown that among 30 selected primers for gametophytes, 297 loci ranging from 200 to 3 000 bp
were obtained in the average of 9.9 loci for each primer. This indicated a high polymorphic rate with RAPD detection. UPGMA
(unweighted pair-group method arithmetic average) analysis showed that each male and female gametophyte of a generation could
be clustered into one pair separately. The genetic distances of the Kelp 901 generation were 0.3212–0.4767, and the maximum
was between F7 and F8 (0.4767). Identity analysis showed that F6 generation was more close to the female parent (0.6593), and F7 generation was more close to the male parent (0.578 8). To the sporophytes study in 24 selected primers for RAPD amplification,
191 loci ranging from 230–2800 bp were obtained, in the average to each primer of 8.0 loci. The heterozygosity to six populations
were male parent (0.2239), female parent (0.1072), F6 (0.2164), F7(0.2286), F8(0.2296) and F9(0.3172). The nearest genetic distance was 0.083 5(F8, F9). Total heterozygosity (HT) of F6, F7, F8 and F9 generations was 0.3186, the average heterozygosity (HS) for F6, F7, F8 and F9 generations was 0.2480, and deduced coefficient of population differentiation (Gst) was 22.2%. Six sequence characterized amplified regions (SCAR) were preliminary screened through RAPD analysis. It needed
to be verified in detail as they are significant for molecular marker assistance in breeding and selectingLaminaria.
Financially supported by 863 program of China (No.2001AA621090) 相似文献
17.
在饲料中分别添加3.0×108kg-1(A组)、1.5×108kg-1(B组)、1.0×108kg-1(C组)的嗜酸小球菌,制成3种实验饲料,以不添加嗜酸小球菌(D组)作为对照,饲养日本鳗鲡60d,以研究嗜酸小球菌对日本鳗鲡生长和免疫的影响。测定了增重率、饵料系数、成活率、血清中一氧化氮含量以及人工感染后的死亡率,并通过电镜观察了小肠壁细胞的微绒毛结构。结果表明A、B、C组和对照组的相对增重率分别为42.31%、75.42%、89.65%和40.32%,饲料系数分别为1.93、1.12、0.98和1.58,C组的相对增重率显著高于其他组,饵料系数则显著低于其他组,成活率也显著提高。电镜观察发现C组和B组的鳗鲡小肠细胞微绒毛排列整齐、细而长,吸收面积增大,从而提高了对饲料利用率,D组鳗鲡小肠细胞的微绒毛稀疏、短,排列不均匀。血清中NO的含量A、B、C组分别比对照组提高了23%、42%和73%。C组人工感染后的死亡率显著低于其他组。实验结果表明,在鳗鲡饲料中添加嗜酸小球菌可以显著促进鳗鲡的生长,降低饵料系数,增强其免疫力。 相似文献
18.
Inorganic carbon utilization in the non-calcifying marine microalgae,Nannochloropsis oculata, Phaeodactylum tricornutum andPorphyridium purpureum was compared with high- and low-calcifying strains ofEmiliania huxleyi grown in artificial seawater medium aerated with either air (0.03% V/V CO2) or CO2-free air. For high-calcifying strain ofE. oculata andP. tricornutem, similar growth patterns were observed in air-and CO2-free air-grown cultures.P. purpureum showed a less final cell density in CO2-free air than in air-grown culture. However, low-calcifying strain ofE. huxleyi was able to grow only in air-grown culture, but not in CO2-free air-grown culture.
Measurements of alkalinity, pH, concentration of dissolved inorganic carbon (DIC) and free CO2 showed different patterns of DIC utilization. WithN. oculata, P. tricornutum andP. purpureum the pattern of DIC utilization was characterized by an increase of pH and a decrease of DIC but a constant alkalinity in
the cultures aerated with air or CO2-free air, suggesting that bicarbonate utilization was concomitant with an efflux of OH−. Both alkalinity and pH were maintained rather constant in air-grown culture of low-calcifying strain ofE. huxleyi, suggesting that diffusive entry of CO2 could meet the requirement of DIC for its photosynthesis and growth. High-calcifying strain ofE. huxleyi, however, showed a pattern of decrease of alkalinity and DIC but an almost constant pH, indicating that bicarbonate was the
major form of inorganic carbon utilised by this organism and bicarbonate uptake is unlikely to be accompanied by an efflux
of OH−.
The final pH values reached byN. oculata, P. tricornutum andP. purpureum in a closed system were 10.75, 10.60 and 9.85 respectively, showing that bicarbonate utilisation is concomitant with an efflux
of OH−. While the final pH of 8.4 in high-calcifyingE. huxleyi suggests that bicarbonate utilization was not accompanied by an efflux of OH−.
Contribution No. 3557 from the Institue of Oceanology, Chinese Academy of Sciences.
This work was supported by NERC grant GRE3/7853 U. K. and partly supported by Bio-Engineering Center, SSTC 96-C01-05-01. 相似文献
19.
A genetic transformation model for the seaweedLaminaria japonica mainly includes the following aspects:
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1.
The method to introduce foreign genes into the kelp,L. japonica
Biolistic bombardment has been proved to be an effective method to bombard foreign DNA through cell walls into intact cells of both sporophytes and gametophytes. The expression ofcat andlacZ was detected in regenerated sporophytes, which suggests that this method could induce random integration of foreign genes.
Promoters to drive gene expression
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2.
The CaMV35S promoter was first used by us to induce the expression of GUS gene in brown algae. But results of further studies suggested that CaMV35S could be a tissue-specific promoter. Our use of SV40 promoter resulted in both transient and stable expression oflacZ andcat in sporophytes or gametophytes. No GUS or LacZ background was found in either sporophytes or gametophytes.The regeneration route of transgenic kelp
The regeneration efficiency of explants is still very low. By using female gametophytes as gene hosts and parthenogenesis as regeneration route, CAT activity and LacZ activity were detected in regenerated sporophytes of parthenogenetic kelp. li]4.|The way to select transgenic kelp
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1.
Results of sensitivity tests showed that kelp was only sensitive to chloramphenicol and hygromycin among many antibiotics. The regenerated sporophytes by parthenogenesis were more sensitive to hygromycin than to chloramphenicol. Resistant kelp was created by transforming female gametophytes with pSV40-CAT and stimulating parthenogenesis followed by selection in medium with lethal concentration of chloramphenicol.
Safety consideration of transgenic kelp
L. japonica was originally introduced from Japan. In China it is a cultured population. The possibility of its negative impact on natural populations is very low. 2) The vectors and target genes used for transformation should be restricted in order to avoid any negative impacts on human health and environment. 3) Specially devised containers (3.6 L, made of 200 μm membrane) were used to ensure that the kelp cannot escape or be eaten by marine animals. 4) To avoid the release of spores, it is very necessary to harvest the kelp at suitable age before the sporangium forms.