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Using 16 microsatellite loci we estimated the parentage of 647 progeny in 10 Jian Carp full-sib families. Cervus 3.0 analysis showed that mean PIC value of 16 microsatellites, mean number of allele, and mean expected heterozygosity were 0.7025, 6.63, and 0.7405, respectively. The combined probability of exclusion was 0.99922456 when both parents were unknown and the combined probability of exclusion was 0.99999557 when only one of the parental genotype was known, with the confidence level of 95%. Further simulations based on allele frequencies suggested that to achieve the requirements of paternity test usually took 8 to 12 microsatellite loci when both parents were unknown and 5 to 8 microsatellite loci when one parent was known. Out of 647 progenies, 94.6% were assigned to their parental pairs without the information of both parents in parentage analysis, which were lower than the theoretical assignment rates predicted by the Cervus simulations. This could be explained by the relationship between the candidate parents or existence of null and by typing errors. The identification of 9 families was useful for linkage analysis of Jian Carp and QTL location, also for marker assisted selection for economical traits.

Based on a full-sib family, the genetic linkage map was constructed with 246 microsatellite and 306 SNP markers, which was used to detect the QTLs for standard length (SL), body depth (H), body thickness (BT), and the ratio of standard length and body depth (SLH) in mirror carp by GridQTL software. The results indicated that a total of 14 related QTLs distributed on the 7 linkage groups were obtained. Seven QTLs were related to standard length, of which the linkage groups of LG6, LG17, LG21, LG23, and LG35 were at 5% significant level, and linkage group LG1 and LG28 were at 1% significant level, which explained 6.6%-12.6% of the phenotypic variance. Three QTLs were identified for body depth on the linkage groups of LG17, LG23 and LG28 (P amp; 0.01), accounting for 11.6%, 12.7%, and 15.6% of the phenotypic variance, respectively. Two QTLs were associated with body thickness on the linkage of LG23 and LG28 (P amp; 0.05), which explained 8.6% and 7.2% of the phenotypic variation, respectively. Two QTLs were responsible for the ratio of standard length and body depth on the linkage of LG21 and LG35 (P amp; 0.05), both of which explained 8.2% of the phenotypic variance. The results provide a useful reference for further candidate gene research and molecular marker assisted selection in mirror carp.

A group of F2 hybrids of mirror carp including 68 individuals was used to construct a linkage map using JoinMap4.0 software. Of 560 markers genotyped, 507 markers (143 SSR markers, 33 EST-SSR markers, and 321 SNP markers) were assigned to the map, which comprised of 62 linkage groups. Quantitative traits loci (QTLs) associated with body length were identified by interval mapping of the software MapQTL 5.0. A linkage group wide permutation test (1 000 replicates) determined the significance of the maximum LOD value over the various intervals analyzed for each linkage group. Twelve QTLs were identified for body length on the linkage groups of BL-1-1 (SNP0137-SNP1481), BL-4-1 (SNP0092-HLJ797), BL-5-1 (SNP1268-HLJ423), BL-7-1 (HLJ870-SNP0702), BL-12-1 (SNP0922-HLJ639), BL-16-1 (HLJE351-SNP0674), BL-25-1 (SNP0394-SNP0862), BL-35-1 (HLJ668-SNP0832), BL-43-1 (SNP0389-SNP1425), BL-47-1 (HLJ057-HLJ1113), BL-47-2 (HLJ1439-HLJ14180), which explained 13.8% to 64.9% of the total variation of body length. Eight major QTLs explained over 20% of the phenotypic variation, which were major QTLs associated with the body length of mirror carp.

Magnetic bead enrich-method and plasmid detection-method were used to isolate microsatellite DNA from Paralichthys olivaceus genome. The microsatellite markers were applied to analyze natural population structure of four populations, which were collected from Dalian, Beidaihe, Dandong, and Qingdao. Two thousand eight hundred and five microsatellite sequence clones were isolated and 3120 microsatellite loci were obtained. From these sequences, 57.97% were perfect, 7.25% were imperfect and 34.78% were compound. This allowed to design 135 pairs of primers with the software Primer Premier 3.0. Seventy-eight pairs were synthesized and 30 pairs were polymorphic. The effective number of alleles ranged from 3.93 to 9.94 (6.95 in average) with observed and expected heterozygosities ranging from 0.532 to 0.895 (0.753 in average) and 0.635 to 0.902 (0.820 in average), respectively. Hardy-Weinberg equilibrium analysis in 30 microsatellite loci by genetic deviation index (d) ranged from -0.247 to 0.512, among which 7 loci had heterozygote excess (d0) and the rest showed heterozygote deficit (damp;0). A dendrogram was constructed based on NJ methods using MEGA3.0 software package. Four populations were divided into two clusters. Dalian population and Dandong population were grouped in one cluster, while Beidaihe population and Qingdao population were classified into another cluster.

The reciprocal intergeneric hybrids between common wheat and Roegneria kamoji were successfully obtained by means of embryo culture. Morphology, chromosome pairing behavior at meiosis, fertility, and resistance to scab of the hybrid F1 and BC1 were studied. The results showed that the morphology of the reciprocal intergeneric hybrids F1 between R. kamoji and T. aestivum cv. Chinese Spring were intermediate type between the two parental species. The chromosome configuration at metaphase I (MI) of pollen mother cell (PMC) in reciprocal F1 was 40.33I + 0.78II + 0.03III and 40.40I + 0.79II, respectively. All of the F1 plants showed complete male sterility, and the seeds of BC1 were obtained by backcrossing with Chinese Spring pollen. The somatic chromosome numbers in BC1 plants of (R. kamoji x Chinese Spring) F1 x Chinese Spring ranged from 55 to 63. Many univalents were observed at MI of PMC, which resulted in the sterility of BC1 plants. Similarly, the chromosome numbers in BC1 plants of (Chinese Spring xR. kamoji) F1 x Chinese Spring also ranged from 55 to 63; however, many bivalents at MI of PMC and fertile pollen were observed resulting in partial fruitfulness in some BC1 plants by self-crossing. A plant (2n=63) with 42 wheat chromosomes and 21 R. kamoji chromosomes was obtained from R. kamoji x Chinese Spring cross, which had a chromosome configuration at MI of 26.40I + 18.30II. Because many univalents existed, this plant showed complete male sterility, and BC1 plants were obtained by back-crossing with Chinese Spring as the pollen parent. The chromosome numbers of BC1 ranged from 40 to 59, which contained less alien chromosomes. Although the morphology of the spike in BC1 plants was similar to that of Chinese Spring, these BC1 plants were still sterile. All F1 and most of the BC1 plants showed high resistance to Fusarium graminearum, which indicated that the resistance to scab from R. kmoji can be transferred into wheat.Microsatellite markers were used to make marker regression analysis on activity of lactate dehydrogenase based on double pseudo-testcross strategy using Windows Map Manager2.0 software. The parents that came from the cross between progenies of Hebao-cold tolerance red carp and Barbless carp and F2 progenies were used as segregating populations. For maker regression, a total of 12 markers associated with activity of lactate dehydrogenase were significant at P0.05 and HLJE222 was significant at P0.01. The variance explained by these loci, ranged from 4.00% to 10.00%. Locus HLJE222 was closely linked to the gene related to activity of lactate dehydrogenase of common carp. For further identification, EST-SSR markers were used to screen the protein and nucleotide database using bioinformatics tools in order to find the homologies. High sequence similarities of HLJE222 marker were observed with the nucleotide sequence of DAZ associated protein 1mRNA of zebrafish(94%), and protein sequence of DAZ associated protein 1(97%). DAZ protein is one of the short chain dehydrogenases, which is an important enzyme in the process of glucose metabolism in the organisms. This family contains a wide variety of dehydrogenases. This indicates that locus HLJE222 was closely linked to the gene associated with activity of lactate dehydrogenase of common carp.

A common carp gynogenetic line including 44 individuals derived from the cross Barbless carp x Hebao-cold tolerance red carp was used to construct a linkage map using 445 markers (265 AFLP markers, 127 SSR markers, 37 EST-SSR markers and 16 RAPD markers). Quantitative traits loci (QTLs) associated with head length, eye diameter, and eye cross were identified by composite interval mapping of the software WinQTLCart2.5. Five QTLs were identified for head length on the linkage group of LG2, LG3, LG40, and LG4, which explained 12.39% to 34.29% of the total variation of the head length. All of their additive effects were negative. Two QTLs were associated with eye diameter on the linkage groups of LG39 (qED-39-1) and LG40 (qED-40-1), which explained 9.77% and 5.62% of the total variation of the eye diameter, respectively. The additive effect of qED-39-1 was positive and that of qED-40-1 was negative. Two QTLs were responsible for eye cross on the linkage group of LG28 and LG20, explaining 8.88% and 8.29% of the total variation of the eye cross, respectively. The additive effect of qEC-28-1 was negative and that of qEC-20-1 was positive.

Twelve microsatellite markers from silver crucian carp were used to investigate the genetic structuring of the diploid and triploid crucian carp from six natural populations in Heilongjiang River System. In the six populations, the number of average allele (A) is from 5.8 to 6.8, the number of effective allele (Ne) is from 2.8 to 4.6, the expected heterozygosity value (He) is from 0.5592 to 0.6962 and the average PIC value is from 0.5962 to 0.648, which indicated that the genetic diversity of the populations investigated is rich. According to genetic deviation index (d), deviation from Hardy-Weinberg equilibrium was found in these populations and all of them showed heterozygosity excess. Kruskal-Wallis test indicated that there was no significant variance in different ploid level and populations. No extra alleles that present with the increase of ploid level were found. The coefficient of gene differentiation between populations(GST)was 0.0398 which indicated low values of genetic differentiation between these populations. Genetic distance was calculated and cluster analysis was also carried out. The results showed that distance between polyploid and diploid in same water was the nearest. Among populations, Songhua River and Ussuri River were the nearest, Xinhuangpao Lake and Moon Bay Lake were nearer, and Shuangfeng reservoir has the largest genetic distance with others.

The natural gynogenetic triploid silver crucian carp (Carassius autatus gibeblio Bloch) provides a good system for studying evolutional genetics of the unisexual and polyploidy vertebrate. Microsatellites are abundant across genomes and show high levels of polymorphism and mutational rate, so they have been widely used for studying evolutional biology. In this study, the mutation rate and pattern at 33 microsatellite loci of silver crucian carp were investigated. As a result, it was found that the only one of 22 offspring had 18 mutant alleles at 15 microsatellite loci. The overall mutation rate of the 33 loci was 1.16x10(-2)/locus/generation (95% confidence interval 6.87x10(-3) and 1.83x10(-2)). The mutation rate in the gynogenetic triploid silver crucian carp was obviously higher than other fish, which was closely related to the transitional phase of parthenogenesis and gamogenesis in the natural gynogenetic fish. The repeat numbers had more than 10 times at 13 loci of the mutant alleles, and there was no obviously different in the mutant rate between the 11 compound microsatellite loci (1.31x10(-2) )and the 21 perfect microsatellite loci(1.00x10(-2)) (P = 0.67). The mutant rate had affinity with repeat numbers instead of repeat types and GC content in flanking sequences of microsatellite. The mutation pattern of silver crucian carp was very complexional, as well as some loci did not follow the Stepwise Mutation Model.

The genetic structure of one breeding population of mirror carp(Cyprinus carpio L.) was analysed using thirty-five polymorphic microsatellite markers. The effective number of alleles (Ae), observed heterozygosity (Ho), expected heterozygosity (He) and polymorphism information content(PIC) were all determined. The Hardy-Weinberg equilibrium was checked by chi-square test. For each locus, 2-7 alleles were detected, with a total of 118 alleles for 35 loci . The value of Ae, Ho, He and PIC showed that the genetic variation of the population was not high .The average effective number of alleles and the mean polymorphism information content were 2.16 and 0.42, respectively, and the observed and expected heterozygosity were 0.431 and 0.4736 , respectively.The probability value of chi-square test showed that more than half of the thirty-five loci have significantly (Plt;0.01) deviated from Hardy-Weinberg equilibrium. The correlation of genotype of each locus and individual phenotype data was analysed , and 4 loci seemed associated with body weight and body size . When compared with the result of QTL mapping of common carp, HLJ319 locus was consistent with the mapping result approximately, which was significantly correlated with body size . Several significantly deviated loci were also analysed, and the possible cause of the kind of deviation was discussed .

Using 30 microsatellite markers and combining quantity characters such as body weight, body size and body width, we evaluated the genetic potential of 3 Germany mirror carp populations. Number of effective alleles (Ae), observed (Ho) and expected (He) heterozygosity values and polymorphic information contents (PIC) were all calculated. 287 alleles and 559 genotypes were detected. The DNA fragment length was 109-400 bp. The Hardy-Weinberg Equilibrium was checked and phenomenon of some disequilibrium were studied according to the test of c2. The result showed that the level of genetic variability was moderate, but genetic potential of Shuanglai population was much lower than that Huanxin and Songpu breeding populations. Polymorphic Information Contents (PIC) of the 3 populations of Germany mirror carp were between 0.08787 and 0.5377, both of highly and moderately polymorphic markers were 13. The number of effective alleles (Ae) were between 1.1014 and 6.4665. The observed (Ho) and expected (He) heterozygosity values were 0.0968-0.9892 and 0.0926-0.8554 respectively. The linkage correlation was analyzed using data of body weight, body size and body width and 30 loci. The result shown that there existed 2 loci, HLJ319 and HLJ693 associated with body size. The HLJ693 locus significantly correlated with body weight character. The HLJ677 locus linked with body width. And then the result were verified in Recombinant Inbred Lines (RIL) of common carp. It shown that the HLJ319 locus was significantly linked with body size, the same as the result of common carp QTL location.

The common carp recombinant inbred lines (RIL) derived from the cross Barbless carp x Hebao-cold tolerance red carp were used as experimental materials in this study. Based on the linkage map constructed with simple sequence repeat (SSR) markers using this RIL population, marker regression and complexity interval mapping were analyzed by Windows Map Manager2.0 software. A P-value of 0.01 was the threshold value of single-marker. A linkage group-wide permutation test (1 000 replicates) determined the significance of the maximum LOD value over the various intervals analyzed for each linkage group. The results are as follows: 1) For maker regression, a total of 7 makers related body size, were at 1% significant level, of which 3 were at 0.1% significant level. The variance explained by these loci, ranged 14.00% to 27.00%. Loci HLJ534, HLJ319, and HLJ370 at 0.1% significant level closely linked to the gene related to body size of common carp; 2) six significant QTLs related to body size were at the 5% linkage group-wide level on these linkage groups, and two of them were at 1% level. The variances explained by these QTLs ranged from 11.33% to 23.12% and their additive effects were not identical. HLJ190-HLJ497 and HLJ479-HLJ483 were major QTLs associated to body size of common carp.

Rainbow trout are cultured widely throughout the world for supplementation in natural ecosystems and for commercial aquaculture. In 1959 it was firstly introduced to China from Korea. After introduction from America and other countries such as Norway, Denmark, and so on, rainbow trout were now cultured in about 20 provinces in China. In this study, microsatellite DNA was employed to assess the genetic variations between 6 cultured populations of rainbow trout (American golden trout, American Donaldsons, Norway, Denmark, Finland, and Bohaizhan). The results showed that in these 6 cultured populations the average number of allele (A) was 2.89 to 4.22; average number of effective allele (Ne) was 2.15 to 2.78; the value of average observed heterozygosity (Ho) in six populations was 0.4802 to 0.6786; the value of average excepted heterozygosity (He) was 0.5052 to 0.6211; and the value of average polymorphism information content (PIC) was 0.4298 to 0.5762. Hardy-Weinberg equilibrium analysis revealed that all of these 6 populations showed a remarkable genetic disequilibrium at loci AY039634, AY039638, AY0396466. Only at locus AF375034 all of 6 populations showed equilibrium. The genetic distance of six cultured populations was calculated and cluster analysis was also carried out.

Seventeen microsatellite markers of Aristichthys nobilis previously discovered by our lab were selected to analyze the genetic diversity and characteristics of two populations of Aristichthys nobilis from Jiangxi and Sichuan provinces. The following parameters were calculated: heterozygosity, polymorphism information content (PIC), valid allele number, allele frequency, genetic distance, genetic similarity coefficient, Hardy-Weinberg balance deflection index and so on. Results show that there are 4 monomorphic and 13 polymorphic markers among the 17 selected microsatellite markers. The average of allele number in each microsatellite locus of the Jiangxi population and Sichuan populations is 3.325 and 3.882, respectively; the average valid allele number is 3.531 and 2.676, respectively; and the number of total alleles of these 17 microsatellite loci is 71. The PIC of polymorphic loci varies between 0.077-0.960, and the average PIC is 0.417. The average observed heterozygosity (Ho) of two populations is 0.385 and 0.360, respectively and the average expected heterzygosity (He) is 0.452 and 0.422, respectively. The genetic similarity coefficient of two populations of Aristichthys nobilis is 0.897 and the genetic distance of these populations is 0.109.