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Semen was treated with ultraviolet irradiation to genetically inactivate the sperm. Gynogenetic haploidy was induced artificially in the German mirror carp, Cyprinus carpio L. A systematic study of the status of early embryonic development, the number of chromosomes, chromosomal banding patterns and fluorescent in situ hybridization (FISH), and a microsatellite analysis were performed. The fertility, hatchability, and survival rates of the gynogenetic group were significantly lower than those of the normal control fertilization group (P

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 P

Forty-seven microsatellite markers were selected to analyze the genomic DNA of 92 progenies derived from the recombinant inbred lines (RIL) of common carp, which came from the cross between Barbless carp and Hebao-cold tolerance red carp. The results showed that a total of 162 different alleles were found, and the number of alleles in each locus was 2 to 6. The DNA fragment length was 100 bp to 444 bp, and the number of mean valid alleles was 1.3069 to 4.2288. The value of heterozygosity was 0.2361 to 0.7677, and the mean polymorphism information content (PIC) was 0.5368. A GLM procedure was used to analyze the effects of these 47 microsatellites on body weight, length and height. Results uncovered HLJ695, HLJ716, HLJ739, HLJ759, HLJ774 and K16 had a significant impact on body weight, length and height, and HLJ776 had a significant impact on height. In addition, the genotypes of these correlative loci were determined.

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 complete mitochondrial genome of Saurogobio dabryi is 16,604 bp in length with 55.88% AT content, including 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region. The termination-associated sequence and six conserved sequence blocks were also identified. Compared all protein-coding genes and whole genome sequence with four species, Saurogobio dabryi has higher similarity with Gobio gobio than others. The mitogenome sequence of Saurogobio dabryi would play an important role in population structure and conservation genetic studies.

During genotyping 150 microsatellites in a F1 family of common carp, six mutations were found at five microsatellite loci. The overall mutation rate of common carp microsatellites was 2.53 X 10(-4) per locus per generation. At five loci, mutations increased the length of alleles by at least one repeat unit, suggesting mutations at microsatellite loci in common carp do not follow strict stepwise mutation model. The data on mutation rates and patterns can facilitate population genetics studies, and provide useful parameters for estimating a long-term effective population size of common carp.

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.

In this paper, population genetic variability and genetic structure of five populations of an important cultivation species, mirror carp (Cyprinus carpio L.) were analyzed using 30 microsatellite loci. The observed (Ho) and expected (He) heterozygosity values, polymorphic information content (PIC) and number of effective alleles (Ae) were all determined. The genetic similarity coefficient and Nei's standard genetic distance were computed based on the allele frequencies. The Hardy-Weinberg equilibrium was checked by chi2 test. Genetic differentiation and hierarchical partition of genetic diversity were evaluated by FST and Nm. A dendrogram was constructed based on UPGMA methods using PHYLIP software package supported by a bootstrap value of 91.0%. Totally 7,083 fragments were procured. Their lengths were from 102 bp to 446 bp. For each locus, 1-16 alleles were amplified, adding up to 356 alleles in all the 5 populations. We found the genetic variability level was relatively high in all five populations, as shown by Ae = 1.07-2.30, He= 0.70-0.78 and PIC=0.69-0.75, respectively. The genetic similarity coefficients were all above 0.52, indicating their close genetic relationships. The UPGMA phylogenetic tree showed mirror carps sampled from Donggang, Fengcheng and Liaozhong were clustered into one group and the other two populations, both collected from Songpu, were grouped together. There were obvious relations between genetic distances and geographical distributions of the five populations. No fragments were amplified from some loci of EST-SSRs, which may suggest the loss of these loci in mirror carp genome or sequence divergence at the primer binding sites. These null alleles may result from selection because functional genes are under more selection pressure than non-encoding loci. Overall, population genetic variation is high for each of the five mirror carp, and the differentiations are also significant among populations.