Analysis of the chloroplast genome of Incarvillea younghusbandii Sprague / 生物工程学报

Incarvillea younghusbandii Sprague is a traditional tonic herb. The roots are used as herbal medicine for nourishing and strengthening, as well as treating postpartum milk deficiency and weakness. In this study, the chloroplast genome of I. younghusbandii was sequenced and assembled by the high-throughput sequencing technology. The sequence characteristics, sequence repeats, codon usage bias, phylogenetic relationships and estimated divergence time of I. younghusbandii were analyzed. The 159 323 bp sequence contained a large single copy (80 197 bp), a small single copy (9 030 bp) and two inverted repeat sequences (35 048 bp). It contained 120 genes, including 77 protein coding genes, 8 ribosomal RNA genes and 35 transfer RNA genes. AAA was the most frequent codon in the chloroplast coding sequence of I. younghusbandii. A total of 42 simple sequence repeats were identified in the chloroplast genome. Phylogenetic analysis revealed I. younghusbandii was mostly like its taxonomically close relative Incarvillea compacta. The divergence between I. younghusbandii and I. compacta was dated to 4.66 million years ago. This study was significant for the scientific conservation and development of resources related to I. compacta. It also provides a basic genetic resource for the subsequent species identification of the genus Incarvillea, and the population genetic diversity study of Bignoniaceae.

Transcriptomic data analyses of Melicope pteleifolia via Illumina high-throughput sequencing technology / 中草药

Objective: To obtain the transcriptome sequence database of Melicope pteleifolia. Methods: The transcriptome sequencing and systematic bioinformatics analysis were carried out using the second generation high-throughput sequencing platform Illumina HiSeqTM 2000 with mixed root, stem and leaf samples of M. pteleifolia. Results: A total of 47 045 040 high quality sequences (clean reads) were obtained by transcriptome sequencing analysis. A total of 67 956 unigenes were assembled by Trinity de novo, with an average length of 787 nt. BLAST analysis showed that 42 749 (61.92%), 31 152 (45.84%), 26 563 (39.09%), and 17 481 (25.72%) unigenes were annotated in NR, Swiss port, KOG and KEGG databases respectively, and 47 groups were involved in three GO classification: biological process, cellular component and molecular function. A total of 9807 unigenes were annotated to 130 KEGG metabolic pathways, 19 secondary metabolic pathways were screened. Twenty-five different KOG functional groups were obtained by the analysis of KOG functional classification. It was predicted that there were 56 families of higher plant transcription factors. A total of 7 748 simple sequence repeats (SSRs) were found by MISA software. The number (4 117) of the tri-nucleotide SSRs was the richest, with a frequency of 53.1%, and the number of the penta-nucleotide SSRs was relatively small, accounting for 2.2%. Conclusion: The transcriptome information characteristics of root, stem, and leaf of M. pteleifolia can be obtained by high-throughput Illumina sequencing technology and bioinformatics analysis, which will lay a foundation for further research on functional gene mining, secondary metabolic pathway analysis and regulation mechanism of M. pteleifolia.

Development and characterization of nuclear microsatellite markers for Eremanthus erythropappus and their transferability across related species

BACKGROUND: We developed simple sequence repeats (SSR) for Eremanthus erythropappus (DC.) MacLeish, an endangered tree species endemic to the Brazilian Savanna and Atlantic Forest biomes, and tested their transferability to two closely related Eremanthus species. RESULTS: Using a genomic library enriched with tandem repeat motifs, we identified 16 primer pairs, and characterized them in two populations. Nine primers amplified the expected size fragments and seven SSRs were polymorphic, providing a total of 38 alleles and an average of 4.22 alleles per marker. The polymorphic information content (PIC) ranged from 0.44 to 0.94 with an average of 0.65. The average observed heterozygosity across all loci varied from 0.61 to 1.00. The observed ( HO ) and expected ( HE ) heterozygosity within the two populations varied from 0.65 to 1.00 and from 0.31 to 1.00, respectively. CONCLUSIONS: These newly developed SSR markers are a powerful tool for population genetic analyses and may be useful in studies on species ecology, evolution, and taxonomy.

SSR and ISSR markers in assessing genetic diversity in Gallus gallus domesticus: a quantitative analysis of scientific production / Marcadores SSR e ISSR na avaliação da diversidade genética em Gallus gallus domesticus: uma análise quantitativa da produção científica

ABSTRACT: Poultry meat is a major source of animal protein in the world. Research indicates a high inbreeding rate derived from a relative absence of heterozygous subpopulations of chicken from different suppliers. Molecular markers can provide information for the genetic basis of chicken consumed in rural areas and help establishing a chicken database for product quality and warranty. The bibliometric research, comprises between 1994 and 2018, from five previously selected databases: Google Scholar, PubMed, ScienceDirect, Scopus and Web of Science, using the following descriptors: 'microsatellites', 'SSR', 'ISSR', 'genetic variability' and 'genetic diversity', all of them coupled to 'chicken' and/or 'birds' results in 66 scientific publications. The publications were then categorized according to their titles to the use of ISSR or SSR markers. They were also addressed by countries according first author cited. The publications data appointed that countries with the height production of poultry meat and hens are the most interested in the genetic diversity study of these species. The SSR markers, due to its more specific characteristic, are more frequently applied to genetic diversity assignment, compared to ISSR.

RESUMO: A carne de frango é uma das principais fontes de proteína animal do mundo. Pesquisas indicam uma alta taxa de endogamia derivada de uma relativa ausência de subpopulações heterozigotas de frango de diferentes fornecedores. Marcadores moleculares podem fornecer informações para a base genética de frango consumido em áreas rurais, e ajudar a estabelecer um banco de dados de frango para qualidade e garantia do produto. A pesquisa bibliométrica compreende entre 1994 e 2018, a partir de cinco bancos de dados selecionados anteriormente: Google Scholar, PubMed, ScienceDirect, Scopus e Web of Science, usando os seguintes descritores: 'microssatélites', 'SSR', 'ISSR', 'variabilidade genética' e 'diversidade genética', todos eles associados a resultados de 'galinha' e / ou 'aves' o que resultou em 66 publicações científicas. As publicações foram então categorizadas de acordo com seus títulos para o uso de marcadores ISSR ou SSR. Eles também foram abordados pelos países, segundo o primeiro autor citado. Os dados das publicações obtidas apontam que os países com grande produção de carnes de frangos são os mais interessados no estudo da diversidade genética dessas espécies. Os marcadores SSR, devido à sua característica mais específica, são frequentemente aplicados à atribuição de diversidade genética, em comparação com o ISSR.

Characterization of the complete chloroplast genome of Nitraria tangutorum, a desert shrub

The chloroplast genome sequence of Nitraria tangutorum, a desert shrub, was sequenced using high-throughput sequencing technology and analysed phylogenetically in the present study. The chloroplast genome is 159,414 bp in length, including a large single copy region of 87,924 bp and small single copy region of 18,318 bp, and a pair of inverted repeat regions of 26,586 bp. The chloroplast genome contains 110 unique genes, including 77 protein-coding genes, four ribosomal RNA genes, and 29 tRNA genes. Most of these genes are present as a single copy and in two or more copies 19 genes occurred. Seventeen genes have one intron, and clpP and ycf3 genes contain two introns. A total of 81 simple sequence repeats (SSRs) were identified, most of them were found to be mononucleotide repeats composed of A/T. In addition to SSRs, 66 repeats were identified, including 41 tandem repeats, 10 palindromic repeats, and 15 forward repeats. The phylogenetic analysis based on 54 protein-coding genes demonstrated a close relationship between N. tangutorum and other plant species in Sapindales. The complete chloroplast genome sequence of N. tangutorum will provide important data for further study of taxonomy and systematics of the genus Nitraria.

Heterotic grouping of late-maturing maize inbred lines based on combining ability and molecular marker studies

Aim: To examine concurrence between yield based and SSR marker based heterotic grouping of late-maturing maize inbred lines. Methodology: A total of 45 F1 crosses derived from 10x10 diallel mating scheme were evaluated along with their parents and hybrid checks across two locations (New Delhi and Dharawada). To group the inbred lines at molecular level, 35 polymorphic SSR primers were used for PCR amplification of repeat sequences from the genomic DNA of each inbred isolated by CTAB method. Cluster analysis was carried out by using NTSYS-pc- 2.02. Results: Analysis of variance revealed significant (P<0.01) variation among the parents and their hybrids across two locations for all the traits. The yield SCA classified 10 late-maturing maize inbred lines into three heterotic groups. Similarly, molecular genetic diversity analysis also categorized the inbred lines into three major clusters. However, correlations between SCA effects and genetic distance were low (r=0.161) for grain yield. Interpretation: Heterosis prediction with the help of molecular markers alone was not found effective. Further, field-testing can be complimented with molecular markers for the elimination of inferior crosses.

Detection of QTL for panicle architecture in F2 population of rice

Panicle traits are the most important agronomic characters which directly relate to yield in rice. Panicle length (PL) being one of the major components of rice panicle structure is controlled by quantitative trait loci (QTLs). In our research, conducted at Research Farm of SKUAST-J, crosses of parental lines K343 and DHMAS were made for generating F2 mapping population, which were then transplanted into the field using augmented design-I. The F2 population was used for phenotypic evaluation, development of linkage map and identification of QTLs on the chromosomes by using SSR markers. A total of 450 SSR markers were used for screening both the parents of which 53 highly polymorphic markers were selected and used for genotyping of 233 genotypes of F2population. Linkage map was generated using MAPMAKER/EXP3.0 software, seven linkage groups were found distributed on 11 chromosomes of rice. QTLs were detected using QTL Cartographer (v2.5) software. Based on 1000 permutation tests, a logarithm of odds (LOD) threshold value 2.0 and 3.0 was set. Composite interval mapping was used to map QTLs in populations derived from bi-parental crosses. The phenotypic data, genotypic data and the genetic linkage map generated identified total three QTLs of which one was identified for PL qPL2, located at 85.01 cM position with 2.1 LOD value and in between the marker intervals RM324–RM208, this QTL explained the phenotype variation by 4.36%. The other two QTLs were identified for spikelet density (SD) qSD3.1 and qSD3.2, located at 28.91 and 39.51 cM, respectively, both with a flanking marker RM6832 on chromosome 3. The LOD value and phenotypic variation explained for qSD3.1 and qSD3.2 was 3.00 and 3.25; 9.70 and 12.34% respectively. The reported QTLs identified in the study suggested a less diversity in the parents used and also the rejection of not so useful markers from the used set of markers for PL and SD.

Population Structure Of Kaempferia Galanga L. From Eastern India

Objective: India has been a producer of a large number of aromatic medicinal plants which serves as a valuable genetic resource for future quality improvement to meet the ever-growing demand of human essential products. Thus, an urgent need arises for germplasm conservation of these high yielding varieties to help the pharmaceutical and other industries. For this understanding, the population structure is essential in order to explore their genetic identification by fingerprinting and molecular characterization. Methods: In the present study DNA was isolated using modified Cetyl Trimethyl Ammonium Bromide (CTAB) method and Polymerase Chain Reaction (PCR) was performed according to standardized method along with its data analysis. This study was undertaken to characterize the highly medicinal Kaempferia galanga collected from 4 different populations of Odisha using the molecular markers as Random Amplified Polymorphic DNA and Inter-Simple Sequence Repeats for the first time. Results: A dendrogram constructed through Sequential Agglomerative Hierarchical and Nested (SAHN) clustering and Unweighted Pair Group Method with Arithmetic mean (UPGMA) analysis showed an average similarity of 0.993 ranging between 0.967 to 1.000. Jaccard’s similarity coefficient of combined markers segregated the genotypes into two main clusters, 1 with six samples and the others at 0.98 similarity coefficient. Conclusion: Hence, the molecular analysis could be further used for the identification of important novel gene present in Kaempferia galanga which can be utilized for future crop improvement as well as pharmacological activities.

Establishment of DNA Fingerprints and Genetic Similarities Analysis of Dendrobium officinale / 中国实验方剂学杂志

This study adopted the 4 pairs of simple sequence repeats(SSR) primers selected by National Resource Center for Chinese Meteria Medica (CACMS) to detect 29 populations of Dendrobium officinale samples from 9 main places of production; 5,7,4 and 3 polymorphism bands were amplified from these 4 pairs of SSR primers. The DNA identities of different populations were constructed by SSR. The 29 D. officinale populations could be divided into 4 classes. The clustering result was related to the places of production. Samples from Yunnan,Guizhou,Sichuan provinces were classified into one category,while samples from Anhui and Guangxi provinces were classified into another category. Samples from Guangdong Danxia,Zhejiang Yongkang,Zhejiang Leqing and Taining belonged to a category. PopGene (version 1.32) software was applied to calculate the genetic similarity of the 29 D. officinale populations. The similarities was between 0.403 4 and 1.0.Based on the genetic similarity,the genetic consistency included three classes,A,B and C. Samples with a similar geographical location and landform environment have higher genetic similarities,which indicate the same genetic background. This paper provides reference information to study the identification, selection and breeding of good varieties.

Transcriptomic data analyses of rhizome of Souliea vaginata via Illumina high-throughput sequencing technology / 中草药

Objective To obtain the transcriptome dataset of rhizome of Souliea vaginata Methods Using the high-throughput illumina sequencing platform Illumina HiSeqTM 2000 150PE, a rhizome transcriptome dataset of S. vaginata was obtained, followed by systemic bioinformatics analyses. Results The transcriptome sequencing analyses produced to a great number of 63 322 086 high quality clean reads. Trinity de novo assembling resulted in a total of 52 575 unigenes with an average length of 909 nt. BLAST analysis indicated that 28 842 (accounting for 54.86% of the total unigenes), 10 712 (20.37%), 9 245 (17.58%), and 11 559 (21.99%) unigenes were successfully annotated in the NR, Swiss-port, KOG, and KEGG databases, respectively. GO classification contained the basic three major groups, including biological process, cellular component, and molecular function, and 45 subgroups. Among them126 KEGG standard pathways were designated, of which 17 were defied as the secondary metabolism. Of all unigenes, 2 215 with protein coding sequences were predicted, and 55 families of plant transcription factors were also identified. MISA prediction yielded a number of 4 609 simple sequence repeats (SSRs), among which the tri-nucleotide SSRs were abundant with 2 106 (45.7%), whereas the penta-nucleotide SSRs were relatively less, accounting for 2.9%. Conclusion The transcriptomic characteristics of S.vaginata rhizome were revealed by the high-throughput Illumina sequencing technology along with bioinformatics analyses, which would be of great importance for the functional gene characterization, secondary metabolism pathway dissections, and their regulatory mechanisms in S. vaginata.

High-throughput transcriptome sequencing of roots of Dictamnus dasycarpus and data analyses / 中草药

Objective To obtain the transcriptome dataset of roots of Dictamnus dasycarpus. Methods The root transcriptome dataset of D. dasycarpus was obtained using the high-throughput sequencing platform Illumina HiSeqTM 2000 150PE, followed by systemic bioinformatics analyses. Results A great number of 69 643 286 high quality clean reads were obtained by the transcriptome sequencing analyses. Using Trinity de novo assembling, a total of 49 050 unigenes were finally obtained, with an average length of 841 nt. BLAST analysis indicated that 31 636 (accounting 64.49% of the total unigenes), 22 367 (45.60%), 19 246 (39.23%), 12 595 (25.68%) unigenes were successfully annotated in the NR, Swiss-port, KOG, and KEGG databases, respectively. And GO classification contained the basic three major groups, including biological process, cellular component, and molecular function with 42 subgroups. A total of 132 KEGG standard metabolic pathways were designated, 18 of which were defied as the secondary metabolism. Further analysis revealed that a total of 90 unigenes were involved in the biosynthesis of various alkaloids. Of all unigenes, 1 908 were predicted to have CDS, and 55 families of plant transcription factors were also identified. Using MISA prediction, 4 579 simple sequence repeats (SSRs) were obtained, among which the tri-nucleotide SSRs were abundant with 2 021 (44.1%), whereas the penta-nucleotide SSRs accounted for 3.5%. Conclusion The root transcriptome of D. dasycarpus revealed by the high-throughput sequencing technology will be important for gene functional characterization, secondary metabolism pathway exploration, and regulation mechanism research in this species.

Transcriptomic analyses of Chloranthus japonicus by RNA-seq / 中草药

Objective To obtain the transcriptome dataset of Chloranthus japonicas. Methods Using the Illumina HiSeqTM 2000 150PE, a rhizome transcriptome of C. japonicus was generated, followed by systemic bioinformatics analyses. Results A total of 68 458 750 high quality clean reads were produced by the transcriptome sequencing. Trinity de novo assembling resulted in a total of 56 096 unigenes with an average length of 801 nt. BLAST analysis indicated that 25 773 (45.94%), 17 801 (31.73%), 16 082 (28.67%), and 9 649 (17.20%) unigenes were successfully annotated in the NR, Swiss-port, KOG, and KEGG databases, respectively. All unigenes were classified into three major groups by GO, including biological process, cellular component, and molecular function, and then, grouped into 40 subgroups. And 131 KEGG standard pathways were designated, 16 of which were defied as the secondary metabolism. Further analysis revealed that a total of 170 unigenes were involved in the biosynthesis of mono-, di-, sesqui-, or triterpene. Meantime, 1 887 unigenes were predicted to contain protein coding sequences. Totally 54 families of transcription factors of higher plant were identified. Using MISA prediction, 8 987 simple sequence repeats (SSRs) were obtained, among which the di-nucleotide SSRs were abundant with 5 948 (66.2%), whereas the penta-nucleotide SSRs were relatively less, accounting for 1.3%. Conclusion The transcriptome of C. japonicus rhizome was generated by RNA-seq along with the identification of unigenes implicated in various terpenes biosynthesis, which will provide a fundamental basis for secondary metabolism pathway dissections and their regulatory mechanisms in this plant species.

Variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta / Genetic variability of twelve microsatellite loci in native Canela-Preta chickens

Esta pesquisa foi realizada com o objetivo de se conhecer a variabilidade genética de 12 loci de microssatélites em galinhas crioulas Canela-Preta. Foram coletadas amostras de sangue de 118 galinhas crioulas Canela-Preta, provenientes de três municípios do estado do Piauí (Oeiras, Queimada Nova e Teresina). Após extração do DNA, foram utilizados marcadores para 12 loci de microssatélites: LEI0192, LEI0209, LEI0212, LEI0217, LEI0221, LEI0234, LEI0237, LEI0248, LEI0258, MCW0081, MCW0183 e MCW0213, que foram amplificados pela técnica de reação em cadeia da polimerase (PCR). Foram obtidos 408 alelos (somando os alelos dos 12 loci), com os fragmentos variando entre 50 e 460 pares de bases. O número de alelos variou de 15 (MCW0081) a 52 (LEI0212), com média de 31,5 alelos por locus. A média de heterozigosidade esperada e o conteúdo de informações polimórficas foram, respectivamente, 0,887 e 0,909. Foram observados desvios no equilíbrio de Hardy-Weinberg e valores positivos do índice de fixação com excesso de homozigotos. Os microssatélites utilizados mostraram-se polimórficos e podem ser usados para investigações genéticas em galinhas Canela-Preta. As galinhas dos plantéis avaliados apresentam grande variabilidade gênica, o que as qualifica como importante fonte de recursos genéticos e, consequentemente, faculta a utilização delas em programas de melhoramento genético animal.(AU)

The aim of this study was to analyze the genetic variability of twelve microsatellite loci in native Canela-Preta chickens. Blood samples were collected from 118 chickens of the breed from five properties in three cities (Oeiras, Queimada Nova and Teresina) of Piauí state. After the DNA extraction, markers were used for twelve microsatellite loci: LEI0192, LEI0209, LEI0212, LEI0217, LEI0221, LEI0234, LEI0237, LEI0248, LEI0258, MCW0081, MCW0183, and MCW0213 that were amplified by polymerase chain reaction technique (PCR). The results showed a total of 408 alleles (adding alleles from the 12 loci) with the fragments ranging between 50 and 460 base pairs, the number of alleles ranged from 15 (MCW0081) to 52 (LEI0212) with an average of 31,5 alleles per locus. The average expected heterozygosity and PIC were, respectively, 0.887 and 0.909. Deviations were observed in the Hardy-Weinberg equilibrium and positive values of the fixation index with excess of homozygotes. It is concluded that the used microsatellites are polymorphic and can, therefore, be used for genetic research in Canela-Preta chickens. The birds of the analyzed cores present great genetic variability, which qualifies them as an important source of genetic resources, which could be used for future animal breeding programs.(AU)

Transcriptome analysis of female and male flower buds of Idesia polycarpa Maxim. var. vestita Diels

Background: Idesia polycarpa Maxim. var. vestita Diels, a dioecious plant, is widely used for biodiesel due to the high oil content of its fruits. However, it is hard to distinguish its sex in the seedling stage, which makes breeding and production problematic as only the female tree can produce fruits, and the mechanisms underlying sex determination and differentiation remain unknown due to the lack of available genomic and transcriptomic information. To begin addressing this issue, we performed the transcriptome analysis of its female and male flower. Results: 28,668,977 and 22,227,992 clean reads were obtained from the female and male cDNA libraries, respectively. After quality checks and de novo assembly, a total of 84,213 unigenes with an average length of 1179 bp were generated and 65,972 unigenes (78.34%) could be matched in at least one of the NR, NT, Swiss-Prot, COG, KEGG and GO databases. Functional annotation of the unigenes uncovered diverse biological functions and processes, including reproduction and developmental process, which may play roles in sex determination and differentiation. The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed many unigenes annotated as metabolic pathways, biosynthesis of secondary metabolites pathways, plant­ pathogen interaction, and plant hormone signal transduction. Moreover, 29,953 simple sequence repeats were identified using the microsatellite software. Conclusion: This work provides the first detailed transcriptome analysis of female and male flower of I. polycarpa and lays foundations for future studies on the molecular mechanisms underlying flower bud development of I. polycarpa.

Transcriptome analysis of Cinnamomum longepaniculatum by high-throughput sequencing

Background: Cinnamomum longepaniculatum is an important commercial crop and the main source of volatile terpenoids. The biosynthesis of key bioactive metabolites of C. longepaniculatum is not well understood because of the lack of available genomic and transcriptomic information. To address this issue, we performed transcriptome sequencing of C. longepaniculatum leaves to identify factors involved in terpenoid metabolite biosynthesis. Results: Transcriptome sequencing of C. longepaniculatum leaves generated over 56 million raw reads. The transcriptome was assembled using the Trinity software and yielded 82,061 unigenes with an average length of 879.43 bp and N50 value of 1387 bp. Furthermore, Benchmarking Universal Single-Copy Orthologs analysis indicated that our assembly is 91% complete. The unigenes were used to query the nonredundant database depending on sequence similarity; 42,809 unigenes were homologous to known genes in different species, with an annotation rate of 42.87%. The transcript abundance and Gene Ontology analyses revealed that numerous unigenes were associated with metabolism, while others were annotated in functional categories including transcription, signal transduction, and secondary metabolism. The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that 19,260 unigenes were involved in 385 metabolic pathways, with 233 unigenes found to be involved in terpenoid metabolism. Moreover, 23,463 simple sequence repeats were identified using the microsatellite identification tool. Conclusion: This is the first detailed transcriptome analysis of C. longepaniculatum. The findings provide insights into the molecular basis of terpenoid biosynthesis and a reference for future studies on the genetics and breeding of C. longepaniculatum.

Analysis on SSR loci information in transcriptome of Houttuynia cordata and its polymorphism / 中草药

Objective: Simple sequence repeats (SSR) loci information in the transcriptome of Houttuynia cordata was analyzed in this study and the more powerful tools were provided for molecular marker-assisted breeding in this plant. Methods: SSR loci were searched in all 63 954 unigenes by using MISA. SSR loci information was analyzed and SSR primers were designed by Primer 3. Furthermore, 50 pairs of primers were randomly selected for the polymorphic analysis on 16 H. cordata plants collected from different habitats. Results: A total of 4 800 SSRs were found in the transcriptome of H. cordata, which distributed in 4 413 unigenes with the distribution frequency of 7.51%. Tri-nucleotide repeat was the main type, accounted for as much as 41.54% of all SSRs, followed by mono-nucleotide repeat motif (27.35%). The mononucleotide repeat motifs of A/T were the predominant repeat type (27.0%). A total of 3068 pairs of SSR primers were designed by using Primer 3. For validating the availability of those SSR primers, 50 pairs of primers were randomly selected for PCR amplification. Among them, 43 pairs of primers (86.0%) produced clear and reproductive bands, which showed polymorphism, and 16 H. cordata plants collected from different places were divided into two groups by UPGMA. Conclusion: There are numerous SSRs in H. cordata transcriptome with high frequency and various types, this will provide the basis for study on genetic diversity and genetic map for H. cordata.

ISSR analysis of genetic background of triploid female and diploid male strains of Siraitia grosvenorii / 中草药

To evaluate the genetic background of triploid female and diploid male strains of Siraitia grosvenorii and provide the biological reference for good varieties breeding of seedless S. grosvenorii. Inter simple sequence repeats (ISSR) marker was developed to analyze the genetic background among 28 samples of S. grosvenorii, and cluster analysis and double principal coordinate analysis were revealed by the NTSYS-pc software and GenAIEx software, respectively. Out of 100 ISSR primers selected, 13 primers were used for amplification and a total of 131 unambiguous bands were obtained, among which 99 (PPB = 75.57%) were polymorphic. The results of cluster analysis and double principal coordinate analysis showed that there was a certain rich of genetic background in triploid female and diploid male strains of S. grosvenorii. But the genetic similarity coefficients of majority were bigger and the genetic distance was closer. The complexity of the genetic background in triploid female and diploid male strains of S. grosvenorii is lower and germplasm innovation strategies should be carried out to enrich the genetic background of the parents of seedless S. grosvenorii.

Cross-species amplification of microsatellite markers in Mycteria leucocephala Pennant 1769: Molted feathers as successful DNA source.

DNA from molted feathers is being increasingly used for genetic studies on birds. However, the DNA obtained from such non-invasive sources is often not of enough quantity and quality for isolation of new microsatellite markers. The present study examined the potential of shed feathers of near threatened Painted Stork as a source of its DNA for cross-species amplification of microsatellites. Thirty-one shed feathers of varying conditions (‘good’ and ‘deteriorated’) and sizes (‘large’, ‘intermediate’ and ‘small’) collected in a north Indian population were used to isolate DNA by a standard isopropanol method and 11 microsatellite markers already developed in the Wood Stork were screened for amplification. Nine plucked feathers from two dead Painted Storks were also used to compare the DNA yield and amplification success. The DNA yield of feathers varied significantly in relation to the calamus size and condition. Among molted feathers, ‘good’ and ‘large’ samples provided more DNA than ‘deteriorated’ and ‘small’ ones, respectively. ‘Large’ plucked feathers yielded more DNA than ‘large’ molted feathers. DNA was almost degraded in all the samples and ratio of absorbance at 260/280 nm varied from 1.0 to 1.8, indicating impurity in many samples. Independent of DNA yields, all microsatellites were cross-amplified in all kinds of feathers, with >80% success in different feather categories. It is concluded that the shed feathers can be successfully used to isolate DNA in the Painted Stork and for cross-species amplification of microsatellites.

Plant regeneration from callus cultures of Vitex trifolia (Lamiales: Lamiaceae): a potential medicinal plant / Regeneración de plantas a partir de cultivos de callos de Vitex trifolia (Lamiales: Lamiaceae): una planta medicinal potencial

Vitex trifolia is a shrub species with popular use as a medicinal plant, for which leaves, roots and flowers have been reported to heal different distresses. The increasing exploitation of these plants has endangered its conservation, and has importantly justified the use of biotechnological tools for their propagation. Our aim was to present an efficient protocol for plant regeneration through organogenesis; and simultaneously, to analyze the genetic homogeneity of the established clonal lines by Randomly Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeat (ISSR) markers. Plantlet regeneration was achieved in callus cultures derived from stem, leaf and petiole explants of V. trifolia on a differently supple mented Murashige & Skoog medium, and incubated at 25±2ºC under a light intensity of 61µmol/m2s from cool white fluorescent lamps and a 16h photoperiod. The rate of shoot bud regeneration was positively correlated with the concentration of hormones in the nutrient media. Shoot buds regenerated more rapidly from stem and petiole explants as compared to leaf explants on medium containing 11.10µM BAP in combination with 0.54µMNAA. Addition of 135.74-271.50µM adenine sulphate (Ads) and 0.72-1.44µM gibberellic acid (GA3) to the culture medium increased the growth of shoot buds. The highest rate of shoot bud regeneration responses was obtained in stem explants using 11.10µM BAP in combination with 0.54µM NAA, 271.50µM Ads and 1.44µM GA3. In vitro rooting of the differentiated shoots was achieved in media containing 1.23µM indole butyric acid (IBA) with 2% (w/v) sucrose. Regenerated plantlets were successfully established in soil with 86% survival under field condition. Randomly Amplified Polymorphic DNA and Inter Simple Sequence Repeat markers analyses have confirmed the genetic uniformity of the regenerated plantlets derived from the second up to fifth subcultures. This protocol may help in mass propagation and conservation of this important medicinal plant of great therapeutic potential.

Vitex trifolia es una especie arbustiva de uso popular como planta medicinal, sus hojas, raíces y flores se han reportado para la cura de diferentes aflicciones. El aumento de la explotación de estas plantas ha puesto en peligro su conservación y ha justificado el uso de herramientas biotecnológicas para su propagación. El objetivo de esta investigación fue presentar un protocolo eficiente para la regeneración de estas plantas a través de la organogénesis, y analizar la homogeneidad genética de las líneas clonales establecidas por ADN polimórfico amplificado aleatoriamente (RAPD) mediante la repetición de marcadores de inter secuencia simple (ISSR). La regeneración de plántulas se logró en cultivos de callos derivados de explantes de tallo, hoja y pecíolo de V. trifolia en un medio diferenciado Murashige & Skoog, que se incubaron a 25±2ºC bajo una intensidad de luz de 61μmol/m2s con lámparas fluorescentes blancas y un fotoperíodo de 16h. La tasa de regeneración de brotes se correlacionó positivamente con la concentración de las hormonas en el medio nutritivo. Los brotes se regeneraron más rápidamente a partir de explantes de tallo y pecíolos en comparación con explantes de hoja. La mayor tasa de regeneración de brotes se obtuvo en los explantes de tallo utilizando 11.10μM BAP en combinación con 0.54μM NAA, 271.50μM Ads y 1.44μM GA3. Este protocolo puede ayudar a la propagación masiva y conservación de esta importante planta medicinal de gran potencial terapéutico.

Evaluation of genetic diversity and linkage disequilibrium in Korean-bred rice varieties using SSR markers

Background: In order to evaluate the variation among different rice types, the genetic diversity in a rice collection composed by 59 breeding lines, 23 landraces, 18 weedy rice lines, and 35 introduced lines that collected from countries worldwide was analyzed using 134 simple sequence repeat markers. Results: In total, 1264 alleles were identified (average, 9.43 per locus). Rare alleles made up a large portion (58.4%) of the detected alleles, and 29 unique alleles associated with rice accessions were also discovered. A model-based structural analysis revealed the presence of three subpopulations. The genetic relationships revealed by the neighbour-joining tree method were fairly consistent with the structure-based membership assignments for most of the accessions. A total of 105 accessions (79.5%) showed a clear relationship to each cluster, while the remaining 27 accessions (20.5%) were categorized as admixtures. Linkage disequilibrium (LD) patterns and distributions are of fundamental importance for genome-wide association mapping. The mean r² value for all intrachromosomal loci pairs was 0.1286. The LD between linked markers decreased with the genetic distance between pairs of linked loci. Conclusions: These results will provide an effective aid for future allele mining, association genetics, mapping and cloning gene(s), germplasm conservation, and improvement programs.