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[Objective] The present paper aimed to study the genetic diversity and population structure of different geographical populations of Triplophysa lixianensi in Lixian county, and to further utilize the genetic germplasm resources of T. lixianensi in Lixian county so as to protect its wild population, the population structure of T. lixianensi in the Yangtze River Basin was investigated in the present study. [ Method] In the study, length composition, body weight composition, length-weight relationships and genetic structure variation of 117 T. lixianensis in four regions of Dadu River were analyzed, and the genetic diversity analysis was performed using D-loop control region of mitochondrial DNA. [Result] The regression equation of body weight and body length was y = 0. 0123x2.9734. The b value was 2. 9734 which was close to 3, indicating that the current growth state was acceptable. A total of 32 variable sites and 28 haplotypes were identified in 878 base pairs of 117 individuals. There was no shared haplotypes among the individuals from four regions. The haplotype diversity of four populations ranged from 0. 637 to 0. 921, and the nucleotide polymorphisms of four populations ranged from 0. 000 91 to 0. 005 70. There was no genetic differentiation between Jinchuan population and Danba population, Luding population and Shimen population, but there was significant genetic differentiation between Luding population and Jinchuan population or Danba population, and between Shimian population and Jinchuan population or Danba population. By constructing the NJ tree, we found that 117 individuals of T. lixianensis formed two independent branches in the evolutionary tree, which was consistent with the genetic distance results of each geographical population. [Conclusion] We suggest that Jinchuan and Danba populations of Dadu River should be managed and protected as a whole protection unit, and that Shimian and Luding populations should also be managed and protected as a whole, while Jinchuan and Danba populations, Shimian and Luding populations should be managed and protected separately. [ABSTRACT FROM AUTHOR]

[Objective] Leaf spot caused by Epicoccum spp. is common on Italian ryegrass (Lolium multiflorum Lam.). The present paper aimed to understand the genetic difference and phylogenic relationship within and among the isolates of Epicoccum causing the leaf spot of Italian ryegrass in southwestern China. [Method] The genomic DNA of 37 representative Epicoccum strains obtained from Huaxi in Guizhou, Nanchuan and Hechuan in Chongqing, Qujing in Yunnan, Chongzhou in Sichuan were extracted by using the Fungal Genome DNA Extraction Kit; Eight strains from different geographical sources were pre-amplified with 35 ISSR primers, and then the primers with more amplified bands were selected to amplify all the tested strains. The data were organized into 0 and 1 matrices, and NTSYSpc (Version 2. 10e), PopGene (Version 1.32) and GenAIEx6. 51 software were used for cluster analysis and principal component analysis respectively. [Result] The bands amplified by 6 primers among the 35 ISSR primers were clear and polymorphisms rich. 63 fragments amplified by the 6 primers were polymorphic, with an average polymorphism rate of 100%. Genetic similarity and cluster analysis demonstrated that the genetic similarity coefficients of the 37 Epicoccum isolates tested ranged from 0. 3100 to 0. 9300. At the level of 0. 4180, 37 Epicoccum isolates were classified into five groups. The average genetic identity (IN) and average genetic distance (D) of the 5 populations were 0. 9168 and 0. 0871 respectively; The average gene diversity index (H) and the average Shannon's information index (I) of the 37 strains were 0. 3628 and 0. 5388 respectively, higher than those of the 5 populations 0. 3121 and 0. 4606. The coefficient of genetic differentiation (Gst) and the gene flow (Nm) of the 37 strains were 0. 1289 and 3. 3794 respectively. [Conclusion] The results of cluster analysis showed that there was a certain correlation between ISSR group classification and isolates classification, and the genetic similarity of the isolates collected from different regions of Southwest China was high. Principal coordinates analysis (PCoA) showed that there was no significant correlation between genetic diversity and geographical distribution. [ABSTRACT FROM AUTHOR]

【Objective】The aim of this paper is to analyze the genetic diversity of faba bean germplasm resources by transcriptome sequencing and SSR molecular marker technology， and to explore the molecular markers associated with bruchid resistance traits in faba bean. So as to provide a reference basis for the conservation and utilization of bruchid resistance germplasm resources and the selection and breeding of new varieties. 【Method】Transcriptome sequencing of two faba bean varieties Y134 and Y078 was performed by PacBio triple full-length sequencing technology combined with RNA-seq.. Based on this， all Unigene of the transcriptome were searched for Unigene containing SSR core motifs using the software MISA， and primers were designed in batch using Primer 3.0. One hundred pairs of SSR primers were randomly selected for genetic diversity analysis of 80 faba bean germplasm resources. 【Result】Fifty of the 100 SSR primer pairs amplified products， with an effective amplification rate of 50%; 32 of the primer pairs showed polymorphism. They accounted for 64% of the effective products and 32% of the total primers. Among the 32 polymorphic primer pairs， each pair amplified 2 to 21 alleles with an average of 6.875; The polymorphic information content （PIC） values ranged from 0.25 to 0.82 with an average of 0.58; The Shannon’s information index varied from 0.34 to 2.31 with an average of 1.21. Based on UPGMA cluster analysis， the 80 faba bean materials were classified into two major groups at a similarity coefficient of 0.70. The first category contained 65 germplasm， including 62 highly resistant （HR） varieties， 2 highly sensitive （HS） varieties and 1 sensitive （S） variety; The second category contained 15 germplasm， 7 highly susceptible （HS） varieties， 2 sensitive （S） varieties， 5 highly resistant （HR） varieties and 1 moderately resistant （MR） variety. 【Conclusion】The SSR markers developed were used to analyze the genetic diversity of 80 faba bean germplasm resources and to lay the theoretical foundation for research on the identification of faba bean germplasm resources resistant to bean weevil and molecular marker-assisted selection for breeding. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the genetic variation characteristics of main agronomic traits between two Cannabis ecotype hybrid F2 populations planted in different ecological environments.【Method】The F2 population from the hybridization of ‘Yunma 1’ and ‘Dame Blanche’ belonging to different subspecies was used as the research object. Ten agronomic traits（plant height, stem diameter, branch number, etc.） were measured in parents and F2 populations planted under three ecological environments. Genetic variation analysis, correlation analysis and generalized heritability estimation of these agronomic traits were carried out.【Result】Eight agronomic traits showed significant differences under three ecological environments（P<0.05）. The average value of most agronomic traits in F2 generation population was between their parents, but the variation of agronomic traits in F2 generation population was large. In 3 ecological environments, coefficient of variation（CV） of 10 agronomic traits was more than 10%. The average CV（the sum of CV in three ecological environments divided by 3） from high to low was as follows: First branch height > fresh weight > branch length > branch number > plant height > stem diameter > compound leaf width> lobular width >length-width ratio of compound leaf> compound leaf length. There was a close relationship among these 10 agronomic traits. Except for the three traits of lobular width, compound leaf width, length-width ratio of compound leaf（leaf shape）, the other seven agronomic traits showed extremely significantly positive correlation in three ecological environments. The data of plant height, branch number, branch length and other agronomic traits complied normal distribution with typical quantitative traits. The variation range of the generalized heritability of the 10 agronomic traits was 29.508% to 82.575%, and could be arranged as the descending sequence: Branch length > plant height > first branch height > compound leaf length > branch number > stem diameter > compound leaf width >lobular width > fresh weight > length-width ratio of compound leaf. The generalized heritability of plant height and branch length exceeded 80%.【Conclusion】In F2 generation population, the 10 agronomic traits showed significant variation and phenotypic segregation. All these traits were closely related to each other and possessed typical genetic characteristics of quantitative traits. This study preliminarily discussed the genetic variation of main agronomic traits in F2 generation of two Cannabis ecotypes, which can provide a theoretical basis for the selection of varieties with different uses and QTL mapping of related traits. [ABSTRACT FROM AUTHOR]

Objective] This paper aims to clarify the genetic diversity of cultivated V. mandarinia in Yunnan province, and to provide a basis for scientific domesticated breeding and bio-control of wasps. [Method] By using the mtDNA COⅠ gene marker, the mtDNA COⅠ gene of 237 domesticated individuals from 8 areas in Yunnan province was sequenced. The genetic diversity, genetic structure and genetic differentiation of the population were then analyzed. [Result] The results showed that a total of 600 bp coding region sequence of the mtDNA COⅠ gene of V. mandarinia was obtained, of which the content of A+T was 68.05%, and apparently showed an obvious AT bias. There were 563 conservative sites and 37 mutative sites, among which the mutation sites accounted for 6.16% of the total analyzed sites. Of 37 mutation sites, there were 30 transformation sites and 7 transposition sites, without insertion or deletion. A total of 12 haplotypes were obtained, of which 6 haplotypes were shared between populations, the rest of haplotypes were not shared between populations. The overall haplotype diversity (Hd) were 0.82958. The mean nucleotide difference (K) was 15.18387, and the nucleotide diversity (Pi) was 0.02526. The genetic distance within each population ranged from 0.00 to 0.0283, and the genetic distance between each population ranged from 0.0001 to 0.0544; there were 50.48% of the mutation originate from inter-population and 49.52% from within population, indicating that the mutation mainly came from outside the population. Fst was 0.50482, the difference was significant (P<0.001）, indicating that there was a greater genetic differentiation between populations. COⅠ gene haplotypes mainly had two clusters, most haplotypes had only one mutation site between them. [Conclusion] The haplotype diversity of the cultured wasp population in Yunnan was high, but the nucleotide diversity was low. The original populations of the cultured V. mandarinia in Yunnan originated from a small number of individuals, and gene exchange was carried out with the local wild populations or introduced populations during the breeding process. There were differences in genetic diversity among the populations. It is recommended that the domesticated populations should use local indigenous sources as much as possible to prevent the introduction of provenances from other places and the gene exchange with wild populations after accidental discharge of domesticated individuals. This would lead to an increase in the genetic diversity of local wild populations, thereby increase the adaptability of wild populations, leading to rapid population expansion. This would help to reduce impact on local biodiversity, especially pollinators. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the genetic structure and variation of four Channa argus populations and three Albino Channa argus populations from different geographical locations. [Method] The DNA of 350 individuals in all populations was detected by 20 pairs of microsatellite primers. The polymorphism and genetic diversity of all microsatellite markers were analyzed. [Result] All 20 pairs of microsatellite primers detected a total of 356 alleles, the number of alleles (Na）ranged from 4 to 40, with an average of 17.8 alleles per locus. The observed heterozygosity (Ho) was between 0.000 to 0.791, and the mean value was 0.578.The expected heterozygosity (He) ranged from 0.31 to 0.91, with an average value of 0.732.The polymorphic information content (PIC) ranged from 0.271 to 0.901, and the average value was 0.700, the Na, Ho, He, and PIC of all the Channa argus populations were higher than those of the Albino Channa argus populations. The genetic differentiation index(FST) of the seven populations ranged from 0.07 876 to 0.40 303, and the genetic differentiation among all populations reached significant level (P<0.05). We divided four Channa argus populations and three Albino Channa argus populations into two groups by molecular variance analysis (AMOVA）, and found that the genetic variation of these groups was mainly from within individuals, accounting for 69.65% of the total genetic variation. The UPGMA hylogenetic tree showed that the Albino Channa argus and Channa argus were clustered into two independent clades. [Conclusion] In this study, the genetic diversity of four Channa argus populations was higher than three Albino Channa argus populations, the protection of genetic diversity of the three populations should be strengthened to avoid inbreeding. This study provides a theoretical basis for the protection and comprehensive utilization of genetic resources of Channa argus and Albino Channa argus. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to address the lack of SSR molecular markers in Illicium verum, based on I. verum transcriptome data, EST-SSR molecular markers were developed and the distribution types and characteristics in transcriptome sequences were revealed. The purpose of this study was to lay a foundation for the study of I. verum at molecular level. [Method] SSR loci were screened from I. verum transcriptome data by SSR search program, and the types, quantity and distribution characteristics of SSR repeat motifs were subjected to statistical analyses. An online design software was used to design SSR primers, and the polymorphism result from primers was evaluated by capillary electrophoresis. The genetic relationship between different I. verum germplasm was analyzed by using selected polymorphic primers. [Result] 8210 SSR loci were obtained from 44 267 Unigenes, The proportion of one EST-SSR loci was 11.11%, the proportion of two or more EST-SSR loci was 3.13%, and the proportion of composite SSR loci was 2.09%. The frequency of SSR was 14.24%, with an average of one SSR every 5.37 kb. Dinucleotides and trinucleotides were the main repeat types among the SSR loci, the highest proportion of dinucleotide repeats was AG/CT, which accounted for 46.03%, the highest proportion of trinucleotide repeats was GAA/CTT, which accounted for 16.58%, and the repetition types and proportion of four, five and six nucleotides were relatively low. The number of replicates of the SSR repeat units ranged from 4 to 40 times, and 5 repetitions were the most, accounting for 22.58%, Then there were 6 repetitions, accounting for 19.83%. The length distribution of microsatellites rangeed from 12 to 80 bp, and 12-15 bp was the most, accounting for 37.39%. Sixteen pairs of primers with high polymorphism were screened by amplification of 100 pairs of primers randomly selected. Na was 3 to 8, Ho was 0.13 to 0.88, He was 0.54 to 0.88, Ne was 2.03 to 5.82, I was 0.83 to 1.84. The primer polymorphism information index was 0.43 to 0.81, with an average of 0.63, indicating that the developed EST-SSR loci had higher polymorphism. The genetic relationship indicated that there were different genetic relationships among different I. verum germplasm. [Conclusion] It is feasible to develop EST-SSR markers based on I.verum transcriptome sequences, and its primers have the advantages of high specificity and high polymorphism, the developed SSR markers can provide basis for genetic diversity analysis, functional gene mining, genetic linkage map construction. [ABSTRACT FROM AUTHOR]

[Obj ective] The present paper aimed to study genetic variation of flower and leaf traits of flax, and to provide basis for germplasm innovation of flax. [Method] Genome-wide association analysis was used to detect SNP sites and candidate genes that were significantly associated with related traits in flax flowers and leaves. [Result] Among the 269 flax materials tested, the most ( 56. 50%) of petals were blue. The most corolla shape was pentagonal ( 42. 75%) . Most of the anthers were blue (86. 61 % ) . The most common leaf color was dark green (58. 73%) . Most of the leaves were lanceolate ( 56. 87%) . Genome-wide association analysis revealed 3 SNP and 8 candidate genes that were significantly associated with flax color. Lusl 0033621 ( pectinesterase) and Lusl 0007409 ( 13-galactoside) genes were involved in the regulation of flax color formation . There were 3 SNP loci significantly associated with corolla shape and 6 candidate genes, among which Lusl0000554 ( leucine-rich PPR motif) gene was closely related to corolla development. One SNP locus was found to be significantly associated with anther color of flax, and five candidate genes were identified. Lusl0010403 ( anthocyanin reductase) gene was directly involved in anthocyanin metabolism. One SNP locus and four candidate genes were detected, among which Lusl0005600 ( PPR motif protein rich in leucine) was involved in regulating leaf color formation. Three SNP loci significantly associated with leaf shape were detected, and five candidate genes were identified, among which Lusl 0033007 gene was involved in regulating the formation of leaf internal structure. [ Conclusion] Flax flowers and anthers are mainly blue. Genome-wide association analysis can detect key candidate genes for association between flowers and leaves. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the molecular characteristics, genetic structure and evolutionary mechanism of cucurbit aphid-borne yellows virus ( CABYV), in order to clarify the epidemic pattern of the virus in the field and formulate long-term sustainable prevention and control strategies which is of great significance. [ Method] 120 melon leaves suspected to be infected with CABYV were randomly collected from Aksu city, Xinjiang. RT-PCR was used to detect the virus. MEGA 7. 0 was used to construct phylogenetic tree, DnaSP vS. 10 was used to analyze the genetic diversity among different sequences, and RDP v. 4. 31 software was used to analyze the possible recombination events of CABYV sequence. [Result] As verified by RT-PCR, 38 samples were CABYV positive, and the detection rate was 31. 67%. A new CABYV-2 was isolated, sequenced and cloned from these positive samples. The length of the genome was 5497 bp, encoding six open reading frames. Compared with 23 CABYV strains isolated from different countries in NCBI database, CABYV-2 had the highest homology with KR231942. 1 and the lowest homology with JF939812. 1. The results of evolutionary tree analysis showed that 24 isolates were divided into two branchesdue to different geographical factors, including CABYV-2 and KR231942. 1 come together and belong to branch 1. The results of genetic diversity and neutral test showed that CABYV was highly variable and population was expanding. The results of recombination analysis showed that there were two recombination events, EU636992. 1 and KR231949.1, which exacerbated the variation of CABYV. [Conclusion] CABYV was isolated from Aksu, Xinjiang and KR231942. 1 from Korea had the closest genetic relationship and the farthest genetic relationship with isolates from European countries. There were great genetic differences between branch 1 and branch 2 isolates. The recombination of cabyv among different hosts intensifies the variation of CABYV recombination and negative selection may be important reasons affecting the genetic variation of CAB YV. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of the present paper is to evaluate the genetic diversity of wild sugarcane germplasm resources, and to explore germplasm resources with breeding potential for directional genetic improvement of sugarcane stress resistance. [Method] In the study, the genetic diversity of 44 wild relatives materials divided into three levels according to inter-species, Saccharum spontaneum, S. arundinaceus were analyzed by ISSR molecular markers. [Result] Using 13 ISSR primers screened in 44 inter-species materials, a total of 261 DNA fragments were amplified, among which 259 ( 99%) were polymorphic; Interspecies polymorphism: Saccharum spontaneum > Saccharum arundinaceus > Erianthus fulvus > Miscanthus floridulus > Eulalia speciosa > Narenga porphyrocoma ; The genetic similarity coefficient among 44 inter-species materials varied from 0. 125 to 0. 710. The UPGMA clustering results of the 44 interspecies materials were basically consistent with the morphological classification. The 12 S. arundinaceus materials were clustered together in 0. 815; S. spontaneum and S . arundinaceus materials were close cluster together in 0. 75, Narenga; Miscanthus, Erianthus materials were closer than others clustering in 0. 73 with Saccharum materials. [Conclusion] The study showed that sugarcane wild germplasm resources had high genetic diversity, which could provide germplasm materials and theoretical basis for sugarcane genetic breeding. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the excellent genes of germplasm resources of Tiebt barley and provide high-quality materials for breeding. [Method] The genetic diversity, clustering and principal component analysis of 13 agronomic traits were carried out by using Excel and SPSS 21. 0 software with 140 germplasm resources from different areas of Tibet [Result] There was rich genetic diversity in barley resources in Tibet, and the coefficient of variation of panicle number per plant among 8 agronomic traits was 43.7%. Cluster analysis divided the 140 materials into five groups at the genetic distances of 6 level, of which 3 5 materials were in group I, 29 materials were in group II, 33 materials were in group Ill, 15 materials were in group N and 28 materials were in group V. The results of principal component analysis showed that when the 8 agronomic traits were simplified into 3 principal components, the cumulative contribution rate was 72. 587 %, and the contribution rate of panicle per plant was the highest, which was 0. 829. [Conclusion] The study provides a scientific basis for the protection and utilization of germplasm resources in Tibet. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to realize the genetic resources and genetic relationship of Henan Big-tail sheep, Small-tail Han sheep and Yuxi Fat-tail sheep.【Method】The genetic diversity of mitochondrion（ mt DNA） D-loop and genetic differentiation of Henan sheep breeds were analyzed in the present study.【Result】50 haplotypes were identified in total,23 in Small-tail Han sheep,25 in Yuxi Fattail sheep, and three in Henan Big-tail sheep. The haplotype diversity were 0. 975,0. 936 and 0. 667,the nucleotide diversity were 0. 0230,0. 0129 and 0. 0270 in Small-tail Han sheep, Yuxi Fat-tail sheep and Henan Big-tail sheep, showing abundant genetic diversity of D-loop sequence in Small-tail Han and Yuxi Fat-tail sheep. The phylogenetic tree gathered these three sheep breeds into three lineages（ A-C）,the three breeds exsisted in all three lineages. The genetic distance of Small-tail Han sheep and Yuxi Fat-tail sheep was the farest（ 0. 0303）. The genetic distance of Henan Big-tail sheep and Small-tail sheep was the nearest（ 0. 0260）. The neutrality test demonstrated that Small-tail Han sheep and Yuxi Fat-tail sheep maintained equilibrium（ P >0. 1）,while Henan Big-tail sheep undergone bottleneck effect（ P <0. 05） in recent decades. The network result showed three maternal origins of Henan sheep breeds. 【Conclusion 】Three Henan sheep breeds showed high genetic diversity. The genetic distances reach the standard of subspecies difference. Small-tail sheep was farthest to Yuxi Fat-tail sheep and nearest to Henan Big-tail sheep. Henan sheep breeds have three maternal origins. The study will provide theoretical basis for the study of genetic relationship and population history, and the protection of genetic resources for Henan sheep breeds. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this paper was to explore the genetic diversity of the tea variety ’Zijuan’ and its mutagenesis progeny.[Method] The selected ’Zijuan’ and ’Zijuan’ mutated progeny were investigated from several aspects of botanical characters, biochemical components and EST-SSR markers. [Result] It was found that the color of buds and leaves of 15 materials were similar to that of ’Zijuan’,only two materials in the leaf shape of mature leaves that were the same as ’Zijuan’,which was lanceolate, and the others were elliptic or long elliptic. There were 9 materials with the same leaf color as ’Zijuan’,all of which are purple green, while 7 materials were yellow-green. Among the variation coefficients of biochemical components in spring and summer, the highest variation coefficient was anthocyanin, which reached 72.16% in spring and 77.86% in summer. The content of anthocyanin changed more in summer than in spring. A total of 165 alleles were detected by microsatellite markers, the average number of alleles was 7.5,the effective number of alleles was 2.562,Shannon information index was 0.997,polymorphic information content was 0.492,observed heterozygosity was 0.629,and expected heterozygosity was 0.565. [Conclusion] The above analysis results of traits, physiological and biochemical characteristics and microsatellite markers showed that the mutant progeny of ’Zijuan’ had a relatively rich genetic diversity. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to understand the genetic diversity of the cultivated Salvia miltiorrhiza populations, the phylogenetic relationship based on the internal transcribed spacer (ITS) regions of the rDNA,and to find out the single nucleotide polymorphism (SNP) fingerprints for the identification of S.miltiorrhiza populations. [Method] PCR amplified, sequenced and compared the ITS sequences of the 42 S.miltiorrhiza populations collected from 33 different regions in China. [Result] The lengths of ITS1,5.8 S rDNA and ITS2 regions in rDNA of S.miltiorrhiza were 203-229,164 and 226-229 bp, respectively; There existed relatively larger difference in length in ITS1,while more nucleotide variations occurred in ITS2;SNP variation sites occurred only in the ITS1 and ITS2 regions with 19 and 37 variation sites and 8.30% and 16.16% variation rates respectively. [Conclusion] Based on the SNP fingerprints of ITS, only 3 cultivated populations could be discriminated from the rest. The phylogenetic trees based on various regions of ITS showed that the cultivated S.miltiorrhiza populations were not genetically related to their geographical sources. [ABSTRACT FROM AUTHOR]