Genetic diversity of cucumber estimated by morpho-physiological and EST-SSR markers.

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Pandey, Sudhakar; Ansari, Waquar Akhter; Pandey, Maneesh; Singh, Bijendra

2018-02-01

In the present study, genetic variation among 40 cucumber genotypes was analyzed by means of morpho-physiological traits and 21 EST-SSR markers. Diversity was observed for morpho-physiological characters like days to 50% female flowering (37-46.9, number of fruits/plant (1.33-5.80), average fruit weight (41-333), vine length (36-364), relative water content (58.5-92.7), electrolyte leakage (15.9-37.1), photosynthetic efficiency (0.40-0.75) and chlorophyll concentration index (11.1-28.6). The pair wise Jaccard similarity coefficient ranged from 0.00 to 0.27 for quantitative traits and 0.24 to 0.96 for EST-SSR markers indicating that the accessions represent genetically diverse populations. With twenty-one EST-SSR markers, polymorphism revealed among 40 cucumber genotypes, number of alleles varied 2-6 with an average 3.05. Polymorphism information content varied from 0.002 to 0.989 (mean = 0.308). The number of effective allele (Ne), expected heterozygosity (He) and unbiased expected heterozygosity (uHe) of these EST-SSRs were 1.079-1.753, 0.074-0.428 and 0.074-0.434, respectively. Same 21 EST-SSR markers transferability checked in four other Cucumis species: snapmelon ( Cucumis melo var. momordica ), muskmelon ( Cucumis melo L.), pickling melon ( Cucumis melo var. conomon ) and wild muskmelon ( Cucumis melo var. agrestis ) with frequency of 61.9, 95.2, 76.2, and 76.2%, respectively. Present study provides useful information on variability, which can assist geneticists with desirable traits for cucumber germplasm utilization. Observed physiological parameters may assists in selection of genotype for abiotic stress tolerance also, EST-SSR markers may be useful for genetic studies in related species.

Exploration of genetic diversity among medicinally important genus Epimedium species based on genomic and EST-SSR marker.

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Yousaf, Zubaida; Hu, Weiming; Zhang, Yanjun; Zeng, Shaohua; Wang, Ying

2015-01-01

Epimedium species has gained prime importance due to their medicinal and economic values. Therefore, in this study, 26 genomic SSR and 10 EST-SSR markers were developed for 13 medicinal species of the Epimedium genus and one out-group species Vancouveria hexandra W. J. Hooker to explore the existing genetic diversity. A total of 100 alleles by genomic SSR and 65 by EST-SSR were detected. The genomic SSR markers were presented between 2-7 alleles per locus. The observed heterozygosity (Ho) and expected heterozygosity (He) ranged from 0.00 to 4.5 and 0.0254 to 2.8108, respectively. Similarly, for EST-SSR, these values were ranged from 3.00 to 4.00 and 1.9650 to 2.7142. The number of alleles for EST-SSR markers ranged from 3 to 10 with an average of 3.51 per loci. It has been concluded that medicinally important species of the genus Epimedium possesses lower intraspecific genetic variation.

Genetic diversity of Phytophthora sojae isolates in Heilongjiang Province in China assessed by RAPD and EST-SSR

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Wu, J. J.; Xu, P. F.; Liu, L. J.; Wang, J. S.; Lin, W. G.; Zhang, S. Z.; Wei, L.

Random-amplified polymorphic DNA (RAPD) and EST-SSR markers were used to estimate the genetic relationship among thirty-nine P.sojae isolates from three locations in Heilongjiang Province, and nine isolates from Ohio in America were made as reference strains. 10 of 50 RAPD primers and 5 of 33 EST-SSR were polymorphic across 48 P.sojae isolates. Similarity values among P.sojae isolates were from 49% to 82% based on the RAPD data. The similarities based on EST-SSR markers ranged from 47% to 85%. The genetic diversity revealed by EST-SSR marker analysis was higher than that obtained from RAPD. The similarity matrices for the SSR data and the RAPD data were moderately correlated (r = 0.47). Genetic similarity coefficients were also relatively lower, which demonstrated complicated genetic background within each location. The high similarity values range revealed the ability of RAPD/EST-SSR markers to distinguish even among morphological similar phytophthora.

Characterization and multiplexing of EST-SSR primers in Cynodon (Poaceae) species1.

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Jewell, Margaret C; Frere, Celine H; Prentis, Peter J; Lambrides, Christopher J; Godwin, Ian D

2010-10-01

Cynodon species are multiple-use grasses that display varying levels of adaptation to biotic and abiotic stress. Previously identified EST-SSR primers were characterized and multiplexed to assess the level of genetic diversity present within a collection of almost 1200 Cynodon accessions from across Australia. • Two multiplex reactions were developed comprising a total of 16 EST-SSR markers. All SSR markers amplified across different Cynodon species and different levels of ploidy. The number of alleles ranged from one to eight per locus and the total number of alleles for the germplasm collection was 79. • The 16 markers show sufficient variation for the characterization of Cynodon core collections and analysis of population genetic diversity in Cynodon grasses.

Expressed Sequence Tag-Simple Sequence Repeat (EST-SSR Marker Resources for Diversity Analysis of Mango (Mangifera indica L.

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Natalie L. Dillon

2014-01-01

Full Text Available In this study, a collection of 24,840 expressed sequence tags (ESTs generated from five mango (Mangifera indica L. cDNA libraries was mined for EST-based simple sequence repeat (SSR markers. Over 1,000 ESTs with SSR motifs were detected from more than 24,000 EST sequences with di- and tri-nucleotide repeat motifs the most abundant. Of these, 25 EST-SSRs in genes involved in plant development, stress response, and fruit color and flavor development pathways were selected, developed into PCR markers and characterized in a population of 32 mango selections including M. indica varieties, and related Mangifera species. Twenty-four of the 25 EST-SSR markers exhibited polymorphisms, identifying a total of 86 alleles with an average of 5.38 alleles per locus, and distinguished between all Mangifera selections. Private alleles were identified for Mangifera species. These newly developed EST-SSR markers enhance the current 11 SSR mango genetic identity panel utilized by the Australian Mango Breeding Program. The current panel has been used to identify progeny and parents for selection and the application of this extended panel will further improve and help to design mango hybridization strategies for increased breeding efficiency.

Gene-based SSR markers for common bean (Phaseolus vulgaris L.) derived from root and leaf tissue ESTs: an integration of the BMc series.

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Blair, Matthew W; Hurtado, Natalia; Chavarro, Carolina M; Muñoz-Torres, Monica C; Giraldo, Martha C; Pedraza, Fabio; Tomkins, Jeff; Wing, Rod

2011-03-22

Sequencing of cDNA libraries for the development of expressed sequence tags (ESTs) as well as for the discovery of simple sequence repeats (SSRs) has been a common method of developing microsatellites or SSR-based markers. In this research, our objective was to further sequence and develop common bean microsatellites from leaf and root cDNA libraries derived from the Andean gene pool accession G19833 and the Mesoamerican gene pool accession DOR364, mapping parents of a commonly used reference map. The root libraries were made from high and low phosphorus treated plants. A total of 3,123 EST sequences from leaf and root cDNA libraries were screened and used for direct simple sequence repeat discovery. From these EST sequences we found 184 microsatellites; the majority containing tri-nucleotide motifs, many of which were GC rich (ACC, AGC and AGG in particular). Di-nucleotide motif microsatellites were about half as common as the tri-nucleotide motif microsatellites but most of these were AGn microsatellites with a moderate number of ATn microsatellites in root ESTs followed by few ACn and no GCn microsatellites. Out of the 184 new SSR loci, 120 new microsatellite markers were developed in the BMc (Bean Microsatellites from cDNAs) series and these were evaluated for their capacity to distinguish bean diversity in a germplasm panel of 18 genotypes. We developed a database with images of the microsatellites and their polymorphism information content (PIC), which averaged 0.310 for polymorphic markers. The present study produced information about microsatellite frequency in root and leaf tissues of two important genotypes for common bean genomics: namely G19833, the Andean genotype selected for whole genome shotgun sequencing from race Peru, and DOR364 a race Mesoamerica subgroup 2 genotype that is a small-red seeded, released variety in Central America. Both race Peru and Mesoamerica subgroup 2 (small red beans) have been understudied in comparison to race Nueva

Development and Validation of EST-SSR Markers from the Transcriptome of Adzuki Bean (Vigna angularis).

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Chen, Honglin; Liu, Liping; Wang, Lixia; Wang, Suhua; Somta, Prakit; Cheng, Xuzhen

2015-01-01

The adzuki bean (Vigna angularis (Ohwi) Ohwi and Ohashi) is an important grain legume of Asia. It is cultivated mainly in China, Japan and Korea. Despite its importance, few genomic resources are available for molecular genetic research of adzuki bean. In this study, we developed EST-SSR markers for the adzuki bean through next-generation sequencing. More than 112 million high-quality cDNA sequence reads were obtained from adzuki bean using Illumina paired-end sequencing technology, and the sequences were de novo assembled into 65,950 unigenes. The average length of the unigenes was 1,213 bp. Among the unigenes, 14,547 sequences contained a unique simple sequence repeat (SSR) and 3,350 sequences contained more than one SSR. A total of 7,947 EST-SSRs were identified as potential molecular markers, with mono-nucleotide A/T repeats (99.0%) as the most abundant motif class, followed by AG/CT (68.4%), AAG/CTT (30.0%), AAAG/CTTT (26.2%), AAAAG/CTTTT (16.1%), and AACGGG/CCCGTT (6.0%). A total of 500 SSR markers were randomly selected for validation, of which 296 markers produced reproducible amplicons with 38 polymorphic markers among the 32 adzuki bean genotypes selected from diverse geographical locations across China. The large number of SSR-containing sequences and EST-SSR markers will be valuable for genetic analysis of the adzuki bean and related Vigna species.

Differential transferability of EST-SSR primers developed from diploid species Pseudoroegneria spicata, Thinopyrum bessarabicum, and Th. elongatum

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Simple sequence repeat technology based on expressed sequence tag (EST-SSR) is a useful genomic tool for genome mapping, characterizing plant species relationships, elucidating genome evolution, and tracing genes on alien chromosome segments. EST-SSR primers developed from three perennial diploid T...

[EST-SSR identification, markers development of Ligusticum chuanxiong based on Ligusticum chuanxiong transcriptome sequences].

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Yuan, Can; Peng, Fang; Yang, Ze-Mao; Zhong, Wen-Juan; Mou, Fang-Sheng; Gong, Yi-Yun; Ji, Pei-Cheng; Pu, De-Qiang; Huang, Hai-Yan; Yang, Xiao; Zhang, Chao

2017-09-01

Ligusticum chuanxiong is a well-known traditional Chinese medicine plant. The study on its molecular markers development and germplasm resources is very important. In this study, we obtained 24 422 unigenes by assembling transcriptome sequencing reads of L. chuanxiong root. EST-SSR was detected and 4 073 SSR loci were identified. EST-SSR distribution and characteristic analysis results showed that the mono-nucleotide repeats were the main repeat types, accounting for 41.0%. In addition, the sequences containing SSR were functionally annotated in Gene Ontology (GO) and KEGG pathway and were assigned to 49 GO categories, 242 KEGG pathways, among them 2 201 sequences were annotated against Nr database. By validating 235 EST-SSRs,74 primer pairs were ultimately proved to have high quality amplification. Subsequently, genetic diversity analysis, UPGMA cluster analysis, PCoA analysis and population structure analysis of 34 L. chuanxiong germplasm resources were carried out with 74 primer pairs. In both UPGMA tree and PCoA results, L. chuanxiong resources were clustered into two groups, which are believed to be partial related to their geographical distribution. In this study, EST-SSRs in L. chuanxiong was firstly identified, and newly developed molecular markers would contribute significantly to further genetic diversity study, the purity detection, gene mapping, and molecular breeding. Copyright© by the Chinese Pharmaceutical Association.

Two EST-derived marker systems for cultivar identification in tree peony.

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Zhang, J J; Shu, Q Y; Liu, Z A; Ren, H X; Wang, L S; De Keyser, E

2012-02-01

Tree peony (Paeonia suffruticosa Andrews), a woody deciduous shrub, belongs to the section Moutan DC. in the genus of Paeonia of the Paeoniaceae family. To increase the efficiency of breeding, two EST-derived marker systems were developed based on a tree peony expressed sequence tag (EST) database. Using target region amplification polymorphism (TRAP), 19 of 39 primer pairs showed good amplification for 56 accessions with amplicons ranging from 120 to 3,000 bp long, among which 99.3% were polymorphic. In contrast, 7 of 21 primer pairs demonstrated adequate amplification with clear bands for simple sequence repeats (SSRs) developed from ESTs, and a total of 33 alleles were found in 56 accessions. The similarity matrices generated by TRAP and EST-SSR markers were compared, and the Mantel test (r = 0.57778, P = 0.0020) showed a moderate correlation between the two types of molecular markers. TRAP markers were suitable for DNA fingerprinting and EST-SSR markers were more appropriate for discriminating synonyms (the same cultivars with different names due to limited information exchanged among different geographic areas). The two sets of EST-derived markers will be used further for genetic linkage map construction and quantitative trait locus detection in tree peony.

Development and Characterization of 1,906 EST-SSR Markers from Unigenes in Jute (Corchorus spp..

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Liwu Zhang

Full Text Available Jute, comprising white and dark jute, is the second important natural fiber crop after cotton worldwide. However, the lack of expressed sequence tag-derived simple sequence repeat (EST-SSR markers has resulted in a large gap in the improvement of jute. Previously, de novo 48,914 unigenes from white jute were assembled. In this study, 1,906 EST-SSRs were identified from these assembled uingenes. Among these markers, di-, tri- and tetra-nucleotide repeat types were the abundant types (12.0%, 56.9% and 21.6% respectively. The AG-rich or GA-rich nucleotide repeats were the predominant. Subsequently, a sample of 116 SSRs, located in genes encoding transcription factors and cellulose synthases, were selected to survey polymorphisms among12 diverse jute accessions. Of these, 83.6% successfully amplified at least one fragment and detected polymorphism among the 12diverse genotypes, indicating that the newly developed SSRs are of good quality. Furthermore, the genetic similarity coefficients of all the 12 accessions were evaluated using 97 polymorphic SSRs. The cluster analysis divided the jute accessions into two main groups with genetic similarity coefficient of 0.61. These EST-SSR markers not only enrich molecular markers of jute genome, but also facilitate genetic and genomic researches in jute.

Development and Evaluation of a Novel Set of EST-SSR Markers Based on Transcriptome Sequences of Black Locust (Robinia pseudoacacia L.).

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Guo, Qi; Wang, Jin-Xing; Su, Li-Zhuo; Lv, Wei; Sun, Yu-Han; Li, Yun

2017-07-07

Black locust ( Robinia pseudoacacia L. of the family Fabaceae) is an ecologically and economically important deciduous tree. However, few genomic resources are available for this forest species, and few effective expressed sequence tag-derived simple sequence repeat (EST-SSR) markers have been developed to date. In this study, paired-end sequencing was used to sequence transcriptomes of R. pseudoacacia by the Illumina HiSeq TM2000 platform, and EST-SSR loci were identified by de novo assembly. Furthermore, a total of 1697 primer pairs were successfully designed, from which 286 primers met the selection screening criteria; 94 pairs were randomly selected and tested for validation using polymerase chain reaction amplification. Forty-five primers were verified as polymorphic, with clear bands. The polymorphism information content values were 0.033-0.765, the number of alleles per locus ranged from 2 to 10, and the observed and expected heterozygosities were 0.000-0.931 and 0.035-0.810, respectively, indicating a high level of informativeness. Subsequently, 45 polymorphic EST-SSR loci were tested for amplification efficiency, using the verified primers, in an additional nine species of Leguminosae, 23 loci were amplified in more than three species, of which two loci were amplified successfully in all species. These EST-SSR markers provide a valuable tool for investigating the genetic diversity and population structure of R . pseudoacacia , constructing a DNA fingerprint database, performing quantitative trait locus mapping, and preserving genetic information.

Three vibrio-resistance related EST-SSR markers revealed by selective genotyping in the clam Meretrix meretrix.

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Nie, Qing; Yue, Xin; Chai, Xueliang; Wang, Hongxia; Liu, Baozhong

2013-08-01

The clam Meretrix meretrix is an important commercial bivalve distributed in the coastal areas of South and Southeast Asia. In this study, marker-trait association analyses were performed based on the stock materials of M. meretrix with different vibrio-resistance profile obtained by selective breeding. Forty-eight EST-SSR markers were screened and 27 polymorphic SSRs of them were genotyped in the clam stocks with different resistance to Vibrio parahaemolyticus (11-R and 11-S) and to Vibrio harveyi (09-R and 09-C). Allele frequency distributions of the SSRs among different stocks were compared using Pearson's Chi-square test, and three functional EST-SSR markers (MM959, MM4765 and MM8364) were found to be associated with vibrio-resistance trait. The 140-bp allele of MM959 and 128-bp allele of MM4765 had significantly higher frequencies in resistant groups (11-R and 09-R) than in susceptive/control groups (11-S and 09-C) (P SSR markers were consistent with the three subgroups distinctions. The putative functions of contig959, contig4765 and contig8364 also suggested that the three SSR-involved genes might play important roles in immunity of M. meretrix. All these results supported that EST-SSR markers MM959, MM4765 and MM8364 were associated with vibrio-resistance and would be useful for marker-assisted selection (MAS) in M. meretrix genetic breeding. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of novel EST-SSR markers for ploidy identification based on de novo transcriptome assembly for Misgurnus anguillicaudatus.

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Feng, Bing; Yi, Soojin V; Zhang, Manman; Zhou, Xiaoyun

2018-01-01

The co-existence of several ploidy types in natural populations makes the cyprinid loach Misgurnus anguillicaudatus an exciting model system to study the genetic and phenotypic consequences of ploidy variations. A first step in such effort is to identify the specific ploidy of an individual. Currently popular methods of karyotyping via cytological preparation or flow cytometry require a large amount of tissue (such as blood) samples, which can be damaging or fatal to the fishes. Here, we developed novel microsatellite markers (SSR markers) from M. anguillicaudatus and show that they can effectively discriminate ploidy using samples collected in a minimally invasive way. Specifically, we generated whole genome transcriptomes from multiple M. anguillicaudatus using the Illumina paired-end sequencing. Approximately 150 million raw reads were assembled into 76,544 non-redundant unigenes. A total of 8,194 potential SSR markers were identified. We selected 98 pairs with more than five tandem repeats for further assays. Out of 45 putative EST-SSR markers that successfully amplified and harbored polymorphism in diploids, 11 markers displayed high variability in tetraploids. We further demonstrate that a set of five EST-SSR markers selected from these are sufficient to distinguish ploidy levels, by first validating them on 69 reference specimens with known ploidy levels and then subsequently using fresh-collected 96 ploidy-unknown specimens. The results from EST-SSR markers are highly concordant with those from independent flow cytometry analysis. The novel EST-SSR markers developed here should facilitate genetic studies of polyploidy in the emerging model system M. anguillicaudatus.

Transcriptome sequencing of mung bean (Vigna radiate L.) genes and the identification of EST-SSR markers.

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Chen, Honglin; Wang, Lixia; Wang, Suhua; Liu, Chunji; Blair, Matthew Wohlgemuth; Cheng, Xuzhen

2015-01-01

Mung bean (Vigna radiate (L.) Wilczek) is an important traditional food legume crop, with high economic and nutritional value. It is widely grown in China and other Asian countries. Despite its importance, genomic information is currently unavailable for this crop plant species or some of its close relatives in the Vigna genus. In this study, more than 103 million high quality cDNA sequence reads were obtained from mung bean using Illumina paired-end sequencing technology. The processed reads were assembled into 48,693 unigenes with an average length of 874 bp. Of these unigenes, 25,820 (53.0%) and 23,235 (47.7%) showed significant similarity to proteins in the NCBI non-redundant protein and nucleotide sequence databases, respectively. Furthermore, 19,242 (39.5%) could be classified into gene ontology categories, 18,316 (37.6%) into Swiss-Prot categories and 10,918 (22.4%) into KOG database categories (E-value SSR), and 2,303 sequences contained more than one SSR together in the same expressed sequence tag (EST). A total of 13,134 EST-SSRs were identified as potential molecular markers, with mono-nucleotide A/T repeats being the most abundant motif class and G/C repeats being rare. In this SSR analysis, we found five main repeat motifs: AG/CT (30.8%), GAA/TTC (12.6%), AAAT/ATTT (6.8%), AAAAT/ATTTT (6.2%) and AAAAAT/ATTTTT (1.9%). A total of 200 SSR loci were randomly selected for validation by PCR amplification as EST-SSR markers. Of these, 66 marker primer pairs produced reproducible amplicons that were polymorphic among 31 mung bean accessions selected from diverse geographical locations. The large number of SSR-containing sequences found in this study will be valuable for the construction of a high-resolution genetic linkage maps, association or comparative mapping and genetic analyses of various Vigna species.

Characterization of the Kenaf (Hibiscus cannabinus) Global Transcriptome Using Illumina Paired-End Sequencing and Development of EST-SSR Markers

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Li, Hui; Li, Defang; Chen, Anguo; Tang, Huijuan; Li, Jianjun; Huang, Siqi

2016-01-01

Kenaf (Hibiscus cannabinus L.) is an economically important natural fiber crop grown worldwide. However, only 20 expressed tag sequences (ESTs) for kenaf are available in public databases. The aim of this study was to develop large-scale simple sequence repeat (SSR) markers to lay a solid foundation for the construction of genetic linkage maps and marker-assisted breeding in kenaf. We used Illumina paired-end sequencing technology to generate new EST-simple sequences and MISA software to mine SSR markers. We identified 71,318 unigenes with an average length of 1143 nt and annotated these unigenes using four different protein databases. Overall, 9324 complementary pairs were designated as EST-SSR markers, and their quality was validated using 100 randomly selected SSR markers. In total, 72 primer pairs reproducibly amplified target amplicons, and 61 of these primer pairs detected significant polymorphism among 28 kenaf accessions. Thus, in this study, we have developed large-scale SSR markers for kenaf, and this new resource will facilitate construction of genetic linkage maps, investigation of fiber growth and development in kenaf, and also be of value to novel gene discovery and functional genomic studies. PMID:26960153

Characterization of the Kenaf (Hibiscus cannabinus) Global Transcriptome Using Illumina Paired-End Sequencing and Development of EST-SSR Markers.

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Li, Hui; Li, Defang; Chen, Anguo; Tang, Huijuan; Li, Jianjun; Huang, Siqi

2016-01-01

Kenaf (Hibiscus cannabinus L.) is an economically important natural fiber crop grown worldwide. However, only 20 expressed tag sequences (ESTs) for kenaf are available in public databases. The aim of this study was to develop large-scale simple sequence repeat (SSR) markers to lay a solid foundation for the construction of genetic linkage maps and marker-assisted breeding in kenaf. We used Illumina paired-end sequencing technology to generate new EST-simple sequences and MISA software to mine SSR markers. We identified 71,318 unigenes with an average length of 1143 nt and annotated these unigenes using four different protein databases. Overall, 9324 complementary pairs were designated as EST-SSR markers, and their quality was validated using 100 randomly selected SSR markers. In total, 72 primer pairs reproducibly amplified target amplicons, and 61 of these primer pairs detected significant polymorphism among 28 kenaf accessions. Thus, in this study, we have developed large-scale SSR markers for kenaf, and this new resource will facilitate construction of genetic linkage maps, investigation of fiber growth and development in kenaf, and also be of value to novel gene discovery and functional genomic studies.

Genetic diversity and relationships among different tomato varieties revealed by EST-SSR markers.

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Korir, N K; Diao, W; Tao, R; Li, X; Kayesh, E; Li, A; Zhen, W; Wang, S

2014-01-08

The genetic diversity and relationship of 42 tomato varieties sourced from different geographic regions was examined with EST-SSR markers. The genetic diversity was between 0.18 and 0.77, with a mean of 0.49; the polymorphic information content ranged from 0.17 to 0.74, with a mean of 0.45. This indicates a fairly high degree of diversity among these tomato varieties. Based on the cluster analysis using unweighted pair-group method with arithmetic average (UPGMA), all the tomato varieties fell into 5 groups, with no obvious geographical distribution characteristics despite their diverse sources. The principal component analysis (PCA) supported the clustering result; however, relationships among varieties were more complex in the PCA scatterplot than in the UPGMA dendrogram. This information about the genetic relationships between these tomato lines helps distinguish these 42 varieties and will be useful for tomato variety breeding and selection. We confirm that the EST-SSR marker system is useful for studying genetic diversity among tomato varieties. The high degree of polymorphism and the large number of bands obtained per assay shows that SSR is the most informative marker system for tomato genotyping for purposes of rights/protection and for the tomato industry in general. It is recommended that these varieties be subjected to identification using an SSR-based manual cultivar identification diagram strategy or other easy-to-use and referable methods so as to provide a complete set of information concerning genetic relationships and a readily usable means of identifying these varieties.

The characterization of a new set of EST-derived simple sequence repeat (SSR markers as a resource for the genetic analysis of Phaseolus vulgaris

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Borba Tereza CO

2011-05-01

Full Text Available Abstract Background Over recent years, a growing effort has been made to develop microsatellite markers for the genomic analysis of the common bean (Phaseolus vulgaris to broaden the knowledge of the molecular genetic basis of this species. The availability of large sets of expressed sequence tags (ESTs in public databases has given rise to an expedient approach for the identification of SSRs (Simple Sequence Repeats, specifically EST-derived SSRs. In the present work, a battery of new microsatellite markers was obtained from a search of the Phaseolus vulgaris EST database. The diversity, degree of transferability and polymorphism of these markers were tested. Results From 9,583 valid ESTs, 4,764 had microsatellite motifs, from which 377 were used to design primers, and 302 (80.11% showed good amplification quality. To analyze transferability, a group of 167 SSRs were tested, and the results showed that they were 82% transferable across at least one species. The highest amplification rates were observed between the species from the Phaseolus (63.7%, Vigna (25.9%, Glycine (19.8%, Medicago (10.2%, Dipterix (6% and Arachis (1.8% genera. The average PIC (Polymorphism Information Content varied from 0.53 for genomic SSRs to 0.47 for EST-SSRs, and the average number of alleles per locus was 4 and 3, respectively. Among the 315 newly tested SSRs in the BJ (BAT93 X Jalo EEP558 population, 24% (76 were polymorphic. The integration of these segregant loci into a framework map composed of 123 previously obtained SSR markers yielded a total of 199 segregant loci, of which 182 (91.5% were mapped to 14 linkage groups, resulting in a map length of 1,157 cM. Conclusions A total of 302 newly developed EST-SSR markers, showing good amplification quality, are available for the genetic analysis of Phaseolus vulgaris. These markers showed satisfactory rates of transferability, especially between species that have great economic and genomic values. Their diversity

Exploiting Illumina Sequencing for the Development of 95 Novel Polymorphic EST-SSR Markers in Common Vetch (Vicia sativa subsp. sativa

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Zhipeng Liu

2014-05-01

Full Text Available The common vetch (Vicia sativa subsp. sativa, a self-pollinating and diploid species, is one of the most important annual legumes in the world due to its short growth period, high nutritional value, and multiple usages as hay, grain, silage, and green manure. The available simple sequence repeat (SSR markers for common vetch, however, are insufficient to meet the developing demand for genetic and molecular research on this important species. Here, we aimed to develop and characterise several polymorphic EST-SSR markers from the vetch Illumina transcriptome. A total number of 1,071 potential EST-SSR markers were identified from 1025 unigenes whose lengths were greater than 1,000 bp, and 450 primer pairs were then designed and synthesized. Finally, 95 polymorphic primer pairs were developed for the 10 common vetch accessions, which included 50 individuals. Among the 95 EST-SSR markers, the number of alleles ranged from three to 13, and the polymorphism information content values ranged from 0.09 to 0.98. The observed heterozygosity values ranged from 0.00 to 1.00, and the expected heterozygosity values ranged from 0.11 to 0.98. These 95 EST-SSR markers developed from the vetch Illumina transcriptome could greatly promote the development of genetic and molecular breeding studies pertaining to in this species.

Development and characterization of novel EST-SSR markers and their application for genetic diversity analysis of Jerusalem artichoke (Helianthus tuberosus L.).

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Mornkham, T; Wangsomnuk, P P; Mo, X C; Francisco, F O; Gao, L Z; Kurzweil, H

2016-10-24

Jerusalem artichoke (Helianthus tuberosus L.) is a perennial tuberous plant and a traditional inulin-rich crop in Thailand. It has become the most important source of inulin and has great potential for use in chemical and food industries. In this study, expressed sequence tag (EST)-based simple sequence repeat (SSR) markers were developed from 40,362 Jerusalem artichoke ESTs retrieved from the NCBI database. Among 23,691 non-redundant identified ESTs, 1949 SSR motifs harboring 2 to 6 nucleotides with varied repeat motifs were discovered from 1676 assembled sequences. Seventy-nine primer pairs were generated from EST sequences harboring SSR motifs. Our results show that 43 primers are polymorphic for the six studied populations, while the remaining 36 were either monomorphic or failed to amplify. These 43 SSR loci exhibited a high level of genetic diversity among populations, with allele numbers varying from 2 to 7, with an average of 3.95 alleles per loci. Heterozygosity ranged from 0.096 to 0.774, with an average of 0.536; polymorphic index content ranged from 0.096 to 0.854, with an average of 0.568. Principal component analysis and neighbor-joining analysis revealed that the six populations could be divided into six clusters. Our results indicate that these newly characterized EST-SSR markers may be useful in the exploration of genetic diversity and range expansion of the Jerusalem artichoke, and in cross-species application for the genus Helianthus.

Development, cross-species/genera transferability of novel EST-SSR markers and their utility in revealing population structure and genetic diversity in sugarcane

KAUST Repository

Singh, Ram K.

2013-07-01

Sugarcane (Saccharum spp. hybrid) with complex polyploid genome requires a large number of informative DNA markers for various applications in genetics and breeding. Despite the great advances in genomic technology, it is observed in several crop species, especially in sugarcane, the availability of molecular tools such as microsatellite markers are limited. Now-a-days EST-SSR markers are preferred to genomic SSR (gSSR) as they represent only the functional part of the genome, which can be easily associated with desired trait. The present study was taken up with a new set of 351 EST-SSRs developed from the 4085 non redundant EST sequences of two Indian sugarcane cultivars. Among these EST-SSRs, TNR containing motifs were predominant with a frequency of 51.6%. Thirty percent EST-SSRs showed homology with annotated protein. A high frequency of SSRs was found in the 5\\'UTR and in the ORF (about 27%) and a low frequency was observed in the 3\\'UTR (about 8%). Two hundred twenty-seven EST-SSRs were evaluated, in sugarcane, allied genera of sugarcane and cereals, and 134 of these have revealed polymorphism with a range of PIC value 0.12 to 0.99. The cross transferability rate ranged from 87.0% to 93.4% in Saccharum complex, 80.0% to 87.0% in allied genera, and 76.0% to 80.0% in cereals. Cloning and sequencing of EST-SSR size variant amplicons revealed that the variation in the number of repeat-units was the main source of EST-SSR fragment polymorphism. When 124 sugarcane accessions were analyzed for population structure using model-based approach, seven genetically distinct groups or admixtures thereof were observed in sugarcane. Results of principal coordinate analysis or UPGMA to evaluate genetic relationships delineated also the 124 accessions into seven groups. Thus, a high level of polymorphism adequate genetic diversity and population structure assayed with the EST-SSR markers not only suggested their utility in various applications in genetics and genomics in

A second generation framework for the analysis of microsatellites in expressed sequence tags and the development of EST-SSR markers for a conifer, Cryptomeria japonica

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Ueno Saneyoshi

2012-04-01

Full Text Available Abstract Background Microsatellites or simple sequence repeats (SSRs in expressed sequence tags (ESTs are useful resources for genome analysis because of their abundance, functionality and polymorphism. The advent of commercial second generation sequencing machines has lead to new strategies for developing EST-SSR markers, necessitating the development of bioinformatic framework that can keep pace with the increasing quality and quantity of sequence data produced. We describe an open scheme for analyzing ESTs and developing EST-SSR markers from reads collected by Sanger sequencing and pyrosequencing of sugi (Cryptomeria japonica. Results We collected 141,097 sequence reads by Sanger sequencing and 1,333,444 by pyrosequencing. After trimming contaminant and low quality sequences, 118,319 Sanger and 1,201,150 pyrosequencing reads were passed to the MIRA assembler, generating 81,284 contigs that were analysed for SSRs. 4,059 SSRs were found in 3,694 (4.54% contigs, giving an SSR frequency lower than that in seven other plant species with gene indices (5.4–21.9%. The average GC content of the SSR-containing contigs was 41.55%, compared to 40.23% for all contigs. Tri-SSRs were the most common SSRs; the most common motif was AT, which was found in 655 (46.3% di-SSRs, followed by the AAG motif, found in 342 (25.9% tri-SSRs. Most (72.8% tri-SSRs were in coding regions, but 55.6% of the di-SSRs were in non-coding regions; the AT motif was most abundant in 3′ untranslated regions. Gene ontology (GO annotations showed that six GO terms were significantly overrepresented within SSR-containing contigs. Forty–four EST-SSR markers were developed from 192 primer pairs using two pipelines: read2Marker and the newly-developed CMiB, which combines several open tools. Markers resulting from both pipelines showed no differences in PCR success rate and polymorphisms, but PCR success and polymorphism were significantly affected by the expected PCR product size

A second generation framework for the analysis of microsatellites in expressed sequence tags and the development of EST-SSR markers for a conifer, Cryptomeria japonica

Science.gov (United States)

2012-01-01

Background Microsatellites or simple sequence repeats (SSRs) in expressed sequence tags (ESTs) are useful resources for genome analysis because of their abundance, functionality and polymorphism. The advent of commercial second generation sequencing machines has lead to new strategies for developing EST-SSR markers, necessitating the development of bioinformatic framework that can keep pace with the increasing quality and quantity of sequence data produced. We describe an open scheme for analyzing ESTs and developing EST-SSR markers from reads collected by Sanger sequencing and pyrosequencing of sugi (Cryptomeria japonica). Results We collected 141,097 sequence reads by Sanger sequencing and 1,333,444 by pyrosequencing. After trimming contaminant and low quality sequences, 118,319 Sanger and 1,201,150 pyrosequencing reads were passed to the MIRA assembler, generating 81,284 contigs that were analysed for SSRs. 4,059 SSRs were found in 3,694 (4.54%) contigs, giving an SSR frequency lower than that in seven other plant species with gene indices (5.4–21.9%). The average GC content of the SSR-containing contigs was 41.55%, compared to 40.23% for all contigs. Tri-SSRs were the most common SSRs; the most common motif was AT, which was found in 655 (46.3%) di-SSRs, followed by the AAG motif, found in 342 (25.9%) tri-SSRs. Most (72.8%) tri-SSRs were in coding regions, but 55.6% of the di-SSRs were in non-coding regions; the AT motif was most abundant in 3′ untranslated regions. Gene ontology (GO) annotations showed that six GO terms were significantly overrepresented within SSR-containing contigs. Forty–four EST-SSR markers were developed from 192 primer pairs using two pipelines: read2Marker and the newly-developed CMiB, which combines several open tools. Markers resulting from both pipelines showed no differences in PCR success rate and polymorphisms, but PCR success and polymorphism were significantly affected by the expected PCR product size and number of SSR

Development and characterization of polymorphic EST based SSR markers in barley (Hordeum vulgare).

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Jo, Won-Sam; Kim, Hye-Yeong; Kim, Kyung-Min

2017-08-01

In barley, breeding using good genetic characteristics can improve the quality or quantity of crop characters from one generation to the next generation. The development of effective molecular markers in barley is crucial for understanding and analyzing the diversity of useful alleles. In this study, we conducted genetic relationship analysis using expressed sequence tag-simple sequence repeat (EST-SSR) markers for barley identification and assessment of barley cultivar similarity. Seeds from 82 cultivars, including 31 each of naked and hulled barley from the Korea Seed and Variety Service and 20 of malting barley from the RDA-Genebank Information Center, were analyzed in this study. A cDNA library of the cultivar Gwanbori was constructed for use in analysis of genetic relationships, and 58 EST-SSR markers were developed and characterized. In total, 47 SSR markers were employed to analyze polymorphisms. A relationship dendrogram based on the polymorphism data was constructed to compare genetic diversity. We found that the polymorphism information content among the examined cultivars was 0.519, which indicates that there is low genetic diversity among Korean barley cultivars. The results obtained in this study may be useful in preventing redundant investment in new cultivars and in resolving disputes over seed patents. Our approach can be used by companies and government groups to develop different cultivars with distinguishable markers. In addition, the developed markers can be used for quantitative trait locus analysis to improve both the quantity and the quality of cultivated barley.

Rapid identification of red-flesh loquat cultivars using EST-SSR markers based on manual cultivar identification diagram strategy.

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Li, X Y; Xu, H X; Chen, J W

2014-04-29

Manual cultivar identification diagram is a new strategy for plant cultivar identification based on DNA markers, providing information to efficiently separate cultivars. We tested 25 pairs of apple EST-SSR primers for amplification of PCR products from loquat cultivars. These EST-SSR primers provided clear amplification products from the loquat cultivars, with a relatively high transferability rate of 84% to loquat; 11 pairs of primers amplified polymorphic products. After analysis of 24 red-fleshed loquat accessions, we found that only 7 pairs of primers could clearly separate all of them. A cultivar identification diagram of the 24 cultivars was constructed using polymorphic bands from the DNA fingerprints and EST-SSR primers. Any two of the 24 cultivars could be rapidly separated from each other, according to the polymorphic bands from the cultivars; the corresponding primers were marked in the correct position on the cultivar identification diagram. This red-flesh loquat cultivar identification diagram can separate the 24 red-flesh loquat cultivars, which is of benefit for loquat cultivar identification for germplasm management and breeding programs.

Development and characterization of EST-SSR markers for Ottelia acuminata var. jingxiensis (Hydrocharitaceae).

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Li, Zhi-Zhong; Lu, Meng-Xue; Saina, Josphat K; Gichira, Andrew W; Wang, Qing-Feng; Chen, Jin-Ming

2017-11-01

Simple sequence repeat (SSR) markers were derived from transcriptomic data for Ottelia acuminata (Hydrocharitaceae), a species comprising five endemic and highly endangered varieties in China. Sixteen novel SSR markers were developed for O. acuminata var. jingxiensis . One to eight alleles per locus were found, with a mean of 2.896. The observed and expected heterozygosity ranged from 0.000 to 1.000 and 0.000 to 0.793, respectively. Interestingly, in cross-varietal amplification, 13 out of the 16 loci were successfully amplified in O. acuminata var. acuminata , and 12 amplified in each of the other three varieties of O. acuminata . These newly developed SSR markers will facilitate further study of genetic variation and provide important genetic data needed for appropriate conservation of natural populations of all varieties of O. acuminata .

simple sequence repeats (EST-SSR)

African Journals Online (AJOL)

Yomi

2012-01-19

Jan 19, 2012 ... 212 primer pairs selected, based on repeat patterns of n≥8 for di-, tri-, tetra- and penta-nucleotide repeat ... Cluster analysis revealed a high genetic similarity among the sugarcane (Saccharum spp.) breeding lines which could reduce the genetic gain in ..... The multiple allele characteristic of SSR com-.

EST-SSR marker revealed effective over biochemical and morphological scepticism towards identification of specific turmeric (Curcuma longa L.) cultivars.

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Sahoo, Ambika; Jena, Sudipta; Kar, Basudeba; Sahoo, Suprava; Ray, Asit; Singh, Subhashree; Joshi, Raj Kumar; Acharya, Laxmikanta; Nayak, Sanghamitra

2017-05-01

Turmeric (Curcuma longa L., family Zingiberaceae) is one of the most economically important plants for its use in food, medicine, and cosmetic industries. Cultivar identification is a major constraint in turmeric, owing to high degree of morphological similarity that in turn, affects its commercialization. The present study addresses this constraint, using EST-SSR marker based, molecular identification of 8 elite cultivars and 88 accessions in turmeric. Fifty EST-SSR primers were screened against eight cultivars of turmeric (Suroma, Roma, Lakadong, Megha, Alleppey Supreme, Kedaram, Pratibha, and Suvarna); out of which 11 primers showed polymorphic banding pattern. The polymorphic information content (PIC) of these primers ranged from 0.13 to 0.48. However, only three SSR loci (CSSR 14, CSSR 15, and CSSR 18) gave reproducible unique banding pattern clearly distinguishing the cultivars 'Lakadong' and 'Suvarna' from other cultivars tested. These three unique SSR markers also proved to be effective in identification of 'Lakadong' cultivars when analysed with 88 accessions of turmeric collected from different agro-climatic regions. Furthermore, two identified cultivars (Lakadong and Suvarna) could also be precisely differentiated when analysed and based on phylogenetic tree, with other 94 genotypes of turmeric. The novel SSR markers can be used for identification and authentication of two commercially important turmeric cultivars 'Lakadong' and 'Suvarna'.

Genetic Diversity and Association of EST-SSR and SCoT Markers with Rust Traits in Orchardgrass (Dactylis glomerata L.).

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Yan, Haidong; Zhang, Yu; Zeng, Bing; Yin, Guohua; Zhang, Xinquan; Ji, Yang; Huang, Linkai; Jiang, Xiaomei; Liu, Xinchun; Peng, Yan; Ma, Xiao; Yan, Yanhong

2016-01-08

Orchardgrass (Dactylis glomerata L.), is a well-known perennial forage species; however, rust diseases have caused a noticeable reduction in the quality and production of orchardgrass. In this study, genetic diversity was assessed and the marker-trait associations for rust were examined using 18 EST-SSR and 21 SCoT markers in 75 orchardgrass accessions. A high level of genetic diversity was detected in orchardgrass with an average genetic diversity index of 0.369. For the EST-SSR and SCoT markers, 164 and 289 total bands were obtained, of which 148 (90.24%) and 272 (94.12%) were polymorphic, respectively. Results from an AMOVA analysis showed that more genetic variance existed within populations (87.57%) than among populations (12.43%). Using a parameter marker index, the efficiencies of the EST-SSR and SCoT markers were compared to show that SCoTs have higher marker efficiency (8.07) than EST-SSRs (4.82). The results of a UPGMA cluster analysis and a STRUCTURE analysis were both correlated with the geographic distribution of the orchardgrass accessions. Linkage disequilibrium analysis revealed an average r² of 0.1627 across all band pairs, indicating a high extent of linkage disequilibrium in the material. An association analysis between the rust trait and 410 bands from the EST-SSR and SCoT markers using TASSEL software revealed 20 band panels were associated with the rust trait in both 2011 and 2012. The 20 bands obtained from association analysis could be used in breeding programs for lineage selection to prevent great losses of orchardgrass caused by rust, and provide valuable information for further association mapping using this collection of orchardgrass.

A fast and cost-effective approach to develop and map EST-SSR markers: oak as a case study

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Cherubini Marcello

2010-10-01

Full Text Available Abstract Background Expressed Sequence Tags (ESTs are a source of simple sequence repeats (SSRs that can be used to develop molecular markers for genetic studies. The availability of ESTs for Quercus robur and Quercus petraea provided a unique opportunity to develop microsatellite markers to accelerate research aimed at studying adaptation of these long-lived species to their environment. As a first step toward the construction of a SSR-based linkage map of oak for quantitative trait locus (QTL mapping, we describe the mining and survey of EST-SSRs as well as a fast and cost-effective approach (bin mapping to assign these markers to an approximate map position. We also compared the level of polymorphism between genomic and EST-derived SSRs and address the transferability of EST-SSRs in Castanea sativa (chestnut. Results A catalogue of 103,000 Sanger ESTs was assembled into 28,024 unigenes from which 18.6% presented one or more SSR motifs. More than 42% of these SSRs corresponded to trinucleotides. Primer pairs were designed for 748 putative unigenes. Overall 37.7% (283 were found to amplify a single polymorphic locus in a reference full-sib pedigree of Quercus robur. The usefulness of these loci for establishing a genetic map was assessed using a bin mapping approach. Bin maps were constructed for the male and female parental tree for which framework linkage maps based on AFLP markers were available. The bin set consisting of 14 highly informative offspring selected based on the number and position of crossover sites. The female and male maps comprised 44 and 37 bins, with an average bin length of 16.5 cM and 20.99 cM, respectively. A total of 256 EST-SSRs were assigned to bins and their map position was further validated by linkage mapping. EST-SSRs were found to be less polymorphic than genomic SSRs, but their transferability rate to chestnut, a phylogenetically related species to oak, was higher. Conclusion We have generated a bin map for oak

tropiTree: An NGS-Based EST-SSR Resource for 24 Tropical Tree Species

Science.gov (United States)

Russell, Joanne R.; Hedley, Peter E.; Cardle, Linda; Dancey, Siobhan; Morris, Jenny; Booth, Allan; Odee, David; Mwaura, Lucy; Omondi, William; Angaine, Peter; Machua, Joseph; Muchugi, Alice; Milne, Iain; Kindt, Roeland; Jamnadass, Ramni; Dawson, Ian K.

2014-01-01

The development of genetic tools for non-model organisms has been hampered by cost, but advances in next-generation sequencing (NGS) have created new opportunities. In ecological research, this raises the prospect for developing molecular markers to simultaneously study important genetic processes such as gene flow in multiple non-model plant species within complex natural and anthropogenic landscapes. Here, we report the use of bar-coded multiplexed paired-end Illumina NGS for the de novo development of expressed sequence tag-derived simple sequence repeat (EST-SSR) markers at low cost for a range of 24 tree species. Each chosen tree species is important in complex tropical agroforestry systems where little is currently known about many genetic processes. An average of more than 5,000 EST-SSRs was identified for each of the 24 sequenced species, whereas prior to analysis 20 of the species had fewer than 100 nucleotide sequence citations. To make results available to potential users in a suitable format, we have developed an open-access, interactive online database, tropiTree (http://bioinf.hutton.ac.uk/tropiTree), which has a range of visualisation and search facilities, and which is a model for the efficient presentation and application of NGS data. PMID:25025376

Characterization and comparison of EST-SSR and TRAP markers for genetic analysis of the Japanese persimmon Diospyros kaki.

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Luo, C; Zhang, F; Zhang, Q L; Guo, D Y; Luo, Z R

2013-01-09

We developed and characterized expressed sequence tags (ESTs)-simple sequence repeats (SSRs) and targeted region amplified polymorphism (TRAP) markers to examine genetic relationships in the persimmon genus Diospyros gene pool. In total, we characterized 14 EST-SSR primer pairs and 36 TRAP primer combinations, which were amplified across 20 germplasms of 4 species in the genus Diospyros. We used various genetic parameters, including effective multiplex ratio (EMR), diversity index (DI), and marker index (MI), to test the utility of these markers. TRAP markers gave higher EMR (24.85) but lower DI (0.33), compared to EST-SSRs (EMR = 3.65, DI = 0.34). TRAP gave a very high MI (8.08), which was about 8 times than the MI of EST-SSR (1.25). These markers were utilized for phylogenetic inference of 20 genotypes of Diospyros kaki Thunb. and allied species, with a result that all kaki genotypes clustered closely and 3 allied species formed an independent group. These markers could be further exploited for large-scale genetic relationship inference.

Development of a novel set of EST-SSR markers and cross-species amplification in Tamarix africana (Tamaricaceae).

Science.gov (United States)

Terzoli, Serena; Beritognolo, Isacco; Sabatti, Maurizio; Kuzminsky, Elena

2010-06-01

Tamarix plants are resistant to abiotic stresses and have become invasive in North America. Their taxonomy is troublesome, and few molecular makers are available to enable species identification or to track the spread of specific invasive genotypes. Transcriptome sequencing projects offer a potential source for the development of new markers. • Thirteen polymorphic simple sequence repeats (SSRs) markers derived from Expressed Sequence Tags (ESTs) from Tamarix hispida, T. androssowii, T. ramosissima, and T. albiflonum were identified and screened on 24 samples of T. africana to detect polymorphism. The number of alleles per locus ranged from two to eight, with an average of 4.3 alleles per locus, and the mean expected heterozygosity was 0.453. • Amplification products of these 13 loci were also generated for T. gallica. These new EST-SSR markers will be useful in genetic characterization of Tamarix, as additional tools for taxonomic clarification, and for studying invasive populations where they are a threat.

Construction of a genetic map using EST-SSR markers and QTL analysis of major agronomic characters in hexaploid sweet potato (Ipomoea batatas (L.) Lam).

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Kim, Jin-Hee; Chung, Il Kyung; Kim, Kyung-Min

2017-01-01

The Sweet potato, Ipomoea batatas (L.) Lam, is difficult to study in genetics and genomics because it is a hexaploid. The sweet potato study not have been performed domestically or internationally. In this study was performed to construct genetic map and quantitative trait loci (QTL) analysis. A total of 245 EST-SSR markers were developed, and the map was constructed by using 210 of those markers. The total map length was 1508.1 cM, and the mean distance between markers was 7.2 cM. Fifteen characteristics were investigated for QTLs analysis. According to those, the Four QTLs were identified, and The LOD score was 3.0. Further studies need to develop molecular markers in terms of EST-SSR markers for doing to be capable of efficient breeding. The genetic map created here using EST-SSR markers will facilitate planned breeding of sweet potato cultivars with various desirable traits.

High polymorphism in Est-SSR loci for cellulose synthase and β-amylase of sugarcane varieties (Saccharum spp.) used by the industrial sector for ethanol production.

Science.gov (United States)

Augusto, Raphael; Maranho, Rone Charles; Mangolin, Claudete Aparecida; Pires da Silva Machado, Maria de Fátima

2015-01-01

High and low polymorphisms in simple sequence repeats of expressed sequence tag (EST-SSR) for specific proteins and enzymes, such as β-amylase, cellulose synthase, xyloglucan endotransglucosylase, fructose 1,6-bisphosphate aldolase, and fructose 1,6-bisphosphatase, were used to illustrate the genetic divergence within and between varieties of sugarcane (Saccharum spp.) and to guide the technological paths to optimize ethanol production from lignocellulose biomass. The varieties RB72454, RB867515, RB92579, and SP813250 on the second stage of cutting, all grown in the state of Paraná (PR), and the varieties RB92579 and SP813250 cultured in the PR state and in Northeastern Brazil, state of Pernambuco (PE), were analyzed using five EST-SSR primers for EstC66, EstC67, EstC68, EstC69, and EstC91 loci. Genetic divergence was evident in the EstC67 and EstC69 loci for β-amylase and cellulose synthase, respectively, among the four sugarcane varieties. An extremely high level of genetic differentiation was also detected in the EstC67 locus from the RB82579 and SP813250 varieties cultured in the PR and PE states. High polymorphism in SSR of the cellulose synthase locus may explain the high variability of substrates used in pretreatment and enzymatic hydrolysis processes, which has been an obstacle to effective industrial adaptations.

Exploiting the transcriptome of Euphrates Poplar, Populus euphratica (Salicaceae to develop and characterize new EST-SSR markers and construct an EST-SSR database.

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Fang K Du

Full Text Available BACKGROUND: Microsatellite markers or Simple Sequence Repeats (SSRs are the most popular markers in population/conservation genetics. However, the development of novel microsatellite markers has been impeded by high costs, a lack of available sequence data and technical difficulties. New species-specific microsatellite markers were required to investigate the evolutionary history of the Euphratica tree, Populus euphratica, the only tree species found in the desert regions of Western China and adjacent Central Asian countries. METHODOLOGY/PRINCIPAL FINDINGS: A total of 94,090 non-redundant Expressed Sequence Tags (ESTs from P. euphratica comprising around 63 Mb of sequence data were searched for SSRs. 4,202 SSRs were found in 3,839 ESTs, with 311 ESTs containing multiple SSRs. The most common motif types were trinucleotides (37% and hexanucleotides (33% repeats. We developed primer pairs for all of the identified EST-SSRs (eSSRs and selected 673 of these pairs at random for further validation. 575 pairs (85% gave successful amplification, of which, 464 (80.7% were polymorphic in six to 24 individuals from natural populations across Northern China. We also tested the transferability of the polymorphic eSSRs to nine other Populus species. In addition, to facilitate the use of these new eSSR markers by other researchers, we mapped them onto Populus trichocarpa scaffolds in silico and compiled our data into a web-based database (http://202.205.131.253:8080/poplar/resources/static_page/index.html. CONCLUSIONS: The large set of validated eSSRs identified in this work will have many potential applications in studies on P. euphratica and other poplar species, in fields such as population genetics, comparative genomics, linkage mapping, QTL, and marker-assisted breeding. Their use will be facilitated by their incorporation into a user-friendly web-based database.

Development and validation of new SSR markers from expressed regions in the garlic genome

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Meryem Ipek

2015-02-01

Full Text Available Only a limited number of simple sequence repeat (SSR markers is available for the genome of garlic (Allium sativum L. despite the fact that SSR markers have become one of the most preferred DNA marker systems. To develop new SSR markers for the garlic genome, garlic expressed sequence tags (ESTs at the publicly available GarlicEST database were screened for SSR motifs and a total of 132 SSR motifs were identified. Primer pairs were designed for 50 SSR motifs and 24 of these primer pairs were selected as SSR markers based on their consistent amplification patterns and polymorphisms. In addition, two SSR markers were developed from the sequences of garlic cDNA-AFLP fragments. The use of 26 EST-SSR markers for the assessment of genetic relationship was tested using 31 garlic genotypes. Twenty six EST-SSR markers amplified 130 polymorphic DNA fragments and the number of polymorphic alleles per SSR marker ranged from 2 to 13 with an average of 5 alleles. Observed heterozygosity and polymorphism information content (PIC of the SSR markers were between 0.23 and 0.88, and 0.20 and 0.87, respectively. Twenty one out of the 31 garlic genotypes were analyzed in a previous study using AFLP markers and the garlic genotypes clustered together with AFLP markers were also grouped together with EST-SSR markers demonstrating high concordance between AFLP and EST-SSR marker systems and possible immediate application of EST-SSR markers for fingerprinting of garlic clones. EST-SSR markers could be used in genetic studies such as genetic mapping, association mapping, genetic diversity and comparison of the genomes of Allium species.

Development of EST-SSR markers in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee based on de novo transcriptomic assemblies.

Directory of Open Access Journals (Sweden)

Jingfang Chen

Full Text Available Flowering Chinese cabbage is one of the most important vegetable crops in southern China. Genetic improvement of various agronomic traits in this crop is underway to meet high market demand in the region, but the progress is hampered by limited number of molecular markers available in this crop. This study aimed to develop EST-SSR markers from transcriptome sequences generated by next-generation sequencing. RNA-seq of eight cabbage samples identified 48,975 unigenes. Of these unigenes, 23,267 were annotated in 56 gene ontology (GO categories, 6,033 were mapped to 131 KEGG pathways, and 7,825 were assigned to clusters of orthologous groups (COGs. From the unigenes, 8,165 EST-SSR loci were identified and 98.57% of them were 1-3 nucleotide repeats with 14.32%, 41.08% and 43.17% of mono-, di- and tri-nucleotide repeats, respectively. Fifty-eight types of motifs were identified with A/T, AG/CT, AT/AT, AC/GT, AAG/CTT and AGG/CCT the most abundant. The lengths of repeated nucleotide sequences in all SSR loci ranged from 12 to 60 bp, with most (88.51% under 20 bp. Among 170 primer pairs were randomly selected from a total of 4,912 SSR primers we designed, 48 yielded unambiguously polymorphic bands with high reproducibility. Cluster analysis using 48 SSRs classified 34 flowering Chinese cabbage cultivars into three groups. A large number of EST-SSR markers identified in this study will facilitate marker-assisted selection in the breeding programs of flowering Chinese cabbage.

Development of EST-SSR markers in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) based on de novo transcriptomic assemblies.

Science.gov (United States)

Chen, Jingfang; Li, Ronghua; Xia, Yanshi; Bai, Guihua; Guo, Peiguo; Wang, Zhiliang; Zhang, Hua; Siddique, Kadambot H M

2017-01-01

Flowering Chinese cabbage is one of the most important vegetable crops in southern China. Genetic improvement of various agronomic traits in this crop is underway to meet high market demand in the region, but the progress is hampered by limited number of molecular markers available in this crop. This study aimed to develop EST-SSR markers from transcriptome sequences generated by next-generation sequencing. RNA-seq of eight cabbage samples identified 48,975 unigenes. Of these unigenes, 23,267 were annotated in 56 gene ontology (GO) categories, 6,033 were mapped to 131 KEGG pathways, and 7,825 were assigned to clusters of orthologous groups (COGs). From the unigenes, 8,165 EST-SSR loci were identified and 98.57% of them were 1-3 nucleotide repeats with 14.32%, 41.08% and 43.17% of mono-, di- and tri-nucleotide repeats, respectively. Fifty-eight types of motifs were identified with A/T, AG/CT, AT/AT, AC/GT, AAG/CTT and AGG/CCT the most abundant. The lengths of repeated nucleotide sequences in all SSR loci ranged from 12 to 60 bp, with most (88.51%) under 20 bp. Among 170 primer pairs were randomly selected from a total of 4,912 SSR primers we designed, 48 yielded unambiguously polymorphic bands with high reproducibility. Cluster analysis using 48 SSRs classified 34 flowering Chinese cabbage cultivars into three groups. A large number of EST-SSR markers identified in this study will facilitate marker-assisted selection in the breeding programs of flowering Chinese cabbage.

SSR allelic variation in almond (Prunus dulcis Mill.).

Science.gov (United States)

Xie, Hua; Sui, Yi; Chang, Feng-Qi; Xu, Yong; Ma, Rong-Cai

2006-01-01

Sixteen SSR markers including eight EST-SSR and eight genomic SSRs were used for genetic diversity analysis of 23 Chinese and 15 international almond cultivars. EST- and genomic SSR markers previously reported in species of Prunus, mainly peach, proved to be useful for almond genetic analysis. DNA sequences of 117 alleles of six of the 16 SSR loci were analysed to reveal sequence variation among the 38 almond accessions. For the four SSR loci with AG/CT repeats, no insertions or deletions were observed in the flanking regions of the 98 alleles sequenced. Allelic size variation of these loci resulted exclusively from differences in the structures of repeat motifs, which involved interruptions or occurrences of new motif repeats in addition to varying number of AG/CT repeats. Some alleles had a high number of uninterrupted repeat motifs, indicating that SSR mutational patterns differ among alleles at a given SSR locus within the almond species. Allelic homoplasy was observed in the SSR loci because of base substitutions, interruptions or compound repeat motifs. Substitutions in the repeat regions were found at two SSR loci, suggesting that point mutations operate on SSRs and hinder the further SSR expansion by introducing repeat interruptions to stabilize SSR loci. Furthermore, it was shown that some potential point mutations in the flanking regions are linked with new SSR repeat motif variation in almond and peach.

Isolation and characterization of twenty-nine novel EST-SSR ...

Indian Academy of Sciences (India)

All results were adjusted for multiple simul- taneous ... ated from HWE after Bonferroni correction (adjusted P = 0.0017) ... ity test of the designed SSR markers. In the 30 examined. S. undulata samples, the PIC value of the 29 newly devel-.

Development of SSR Markers and Assessment of Genetic Diversity in Medicinal Chrysanthemum morifolium Cultivars.

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Feng, Shangguo; He, Renfeng; Lu, Jiangjie; Jiang, Mengying; Shen, Xiaoxia; Jiang, Yan; Wang, Zhi'an; Wang, Huizhong

2016-01-01

Chrysanthemum morifolium, is a well-known flowering plant worldwide, and has a high commercial, floricultural, and medicinal value. In this study, simple-sequence repeat (SSR) markers were generated from EST datasets and were applied to assess the genetic diversity among 32 cultivars. A total of 218 in silico SSR loci were identified from 7300 C. morifolium ESTs retrieved from GenBank. Of all SSR loci, 61.47% of them (134) were hexa-nucleotide repeats, followed by tri-nucleotide repeats (17.89%), di-nucleotide repeats (12.39%), tetra-nucleotide repeats (4.13%), and penta-nucleotide repeats (4.13%). In this study, 17 novel EST-SSR markers were verified. Along with 38 SSR markers reported previously, 55 C. morifolium SSR markers were selected for further genetic diversity analysis. PCR amplification of these EST-SSRs produced 1319 fragments, 1306 of which showed polymorphism. The average polymorphism information content of the SSR primer pairs was 0.972 (0.938-0.993), which showed high genetic diversity among C. morifolium cultivars. Based on SSR markers, 32 C. morifolium cultivars were separated into two main groups by partitioning of the clusters using the unweighted pair group method with arithmetic mean dendrogram, which was further supported by a principal coordinate analysis plot. Phylogenetic relationship among C. morifolium cultivars as revealed by SSR markers was highly consistent with the classification of medicinal C. morifolium populations according to their origin and ecological distribution. Our results demonstrated that SSR markers were highly reproducible and informative, and could be used to evaluate genetic diversity and relationships among medicinal C. morifolium cultivars.

Construction of new EST-SSRs for Fusarium resistant wheat breeding.

Science.gov (United States)

Yumurtaci, Aysen; Sipahi, Hulya; Al-Abdallat, Ayed; Jighly, Abdulqader; Baum, Michael

2017-06-01

Surveying Fusarium resistance in wheat with easy applicable molecular markers such as simple sequence repeats (SSRs) is a prerequest for molecular breeding. Expressed sequence tags (ESTs) are one of the main sources for development of new SSR candidates. Therefore, 18.292 publicly available wheat ESTs were mined and genotyping of newly developed 55 EST-SSR derived primer pairs produced clear fragments in ten wheat cultivars carrying different levels of Fusarium resistance. Among the proved markers, 23 polymorphic EST-SSRs were obtained and related alleles were mostly found on B and D genome. Based on the fragment profiling and similarity analysis, a 327bp amplicon, which was a product of contig 1207 (chromosome 5BL), was detected only in Fusarium head blight (FHB) resistant cultivars (CM82036 and Sumai) and the amino acid sequences showed a similarity to pathogen related proteins. Another FHB resistance related EST-SSR, Contig 556 (chromosome 1BL) produced a 151bp fragment in Sumai and was associated to wax2-like protein. A polymorphic 204bp fragment, derived from Contig 578 (chromosome 1DL), was generated from root rot (FRR) resistant cultivars (2-49; Altay2000 and Sunco). A total of 98 alleles were displayed with an average of 1.8 alleles per locus and the polymorphic information content (PIC) ranged from 0.11 to 0.78. Dendrogram tree with two main and five sub-groups were displayed the highest genetic relationship between FRR resistant cultivars (2-49 and Altay2000), FRR sensitive cultivars (Seri82 and Scout66) and FHB resistant cultivars (CM82036 and Sumai). Thus, exploitation of these candidate EST-SSRs may help to genotype other wheat sources for Fusarium resistance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development of eSSR-Markers in Setaria italica and Their Applicability in Studying Genetic Diversity, Cross-Transferability and Comparative Mapping in Millet and Non-Millet Species.

Science.gov (United States)

Kumari, Kajal; Muthamilarasan, Mehanathan; Misra, Gopal; Gupta, Sarika; Subramanian, Alagesan; Parida, Swarup Kumar; Chattopadhyay, Debasis; Prasad, Manoj

2013-01-01

Foxtail millet (Setariaitalica L.) is a tractable experimental model crop for studying functional genomics of millets and bioenergy grasses. But the limited availability of genomic resources, particularly expressed sequence-based genic markers is significantly impeding its genetic improvement. Considering this, we attempted to develop EST-derived-SSR (eSSR) markers and utilize them in germplasm characterization, cross-genera transferability and in silico comparative mapping. From 66,027 foxtail millet EST sequences 24,828 non-redundant ESTs were deduced, representing ~16 Mb, which revealed 534 (~2%) eSSRs in 495 SSR containing ESTs at a frequency of 1/30 kb. A total of 447 pp were successfully designed, of which 327 were mapped physically onto nine chromosomes. About 106 selected primer pairs representing the foxtail millet genome showed high-level of cross-genera amplification at an average of ~88% in eight millets and four non-millet species. Broad range of genetic diversity (0.02-0.65) obtained in constructed phylogenetic tree using 40 eSSR markers demonstrated its utility in germplasm characterizations and phylogenetics. Comparative mapping of physically mapped eSSR markers showed considerable proportion of sequence-based orthology and syntenic relationship between foxtail millet chromosomes and sorghum (~68%), maize (~61%) and rice (~42%) chromosomes. Synteny analysis of eSSRs of foxtail millet, rice, maize and sorghum suggested the nested chromosome fusion frequently observed in grass genomes. Thus, for the first time we had generated large-scale eSSR markers in foxtail millet and demonstrated their utility in germplasm characterization, transferability, phylogenetics and comparative mapping studies in millets and bioenergy grass species.

Development of 23 novel polymorphic EST-SSR markers for the endangered relict conifer Metasequoia glyptostroboides.

Science.gov (United States)

Jin, Yuqing; Bi, Quanxin; Guan, Wenbin; Mao, Jian-Feng

2015-09-01

Metasequoia glyptostroboides is an endangered relict conifer species endemic to China. In this study, expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed using transcriptome mining for future genetic and functional studies. We collected 97,565 unigene sequences generated by 454 pyrosequencing. A bioinformatics analysis identified 2087 unique and putative microsatellites, from which 96 novel microsatellite markers were developed. Fifty-three of the 96 primer sets successfully amplified clear fragments of the expected sizes; 23 of those loci were polymorphic. The number of alleles per locus ranged from two to eight, with an average of three, and the observed and expected heterozygosity values ranged from 0 to 1.0 and 0.117 to 0.813, respectively. These microsatellite loci will enrich the genetic resources to develop functional studies and conservation strategies for this endangered relict species.

Functional molecular markers (EST-SSR) in the full-sib reciprocal recurrent selection program of maize (Zea mays L.).

Science.gov (United States)

Galvão, K S C; Ramos, H C C; Santos, P H A D; Entringer, G C; Vettorazzi, J C F; Pereira, M G

2015-07-03

This study aimed to improve grain yield in the full-sib reciprocal recurrent selection program of maize from the North Fluminense State University. In the current phase of the program, the goal is to maintain, or even increase, the genetic variability within and among populations, in order to increase heterosis of the 13th cycle of reciprocal recurrent selection. Microsatellite expressed sequence tags (EST-SSRs) were used as a tool to assist the maximization step of genetic variability, targeting the functional genome. Eighty S1 progenies of the 13th recur-rent selection cycle, 40 from each population (CIMMYT and Piranão), were analyzed using 20 EST-SSR loci. Genetic diversity, observed heterozygosity, information content of polymorphism, and inbreeding co-efficient were estimated. Subsequently, analysis of genetic dissimilarity, molecular variance, and a graphical dispersion of genotypes were conducted. The number of alleles in the CIMMYT population ranged from 1 to 6, while in the Piranão population the range was from 2 to 8, with a mean of 3.65 and 4.35, respectively. As evidenced by the number of alleles, the Shannon index showed greater diversity for the Piranão population (1.04) in relation to the CIMMYT population (0.89). The genic SSR markers were effective in clustering genotypes into their respective populations before selection and an increase in the variation between populations after selection was observed. The results indicate that the study populations have expressive genetic diversity, which cor-responds to the functional genome, indicating that this strategy may contribute to genetic gain, especially in association with the grain yield of future hybrids.

Molecular characterization of a peanut variety and its derivatives based on SSR and COP analysis

Institute of Scientific and Technical Information of China (English)

Xiaoping REN; Boshou LIAO; Huifang JIANG; Zhongyuan YUAN; Yuning CHEN; Xiaojing ZHOU; Li HUANG; Jiaquan HUANG; Yong LEI; Liying YAN

2016-01-01

Despite the economic importance of the peanut,no studies have been carried out to determine the correlation between genetic distances based on molecular markers and on coefficient of parentage (COP) data.In this study,simple sequence repeat (SSR) and pedigree data were used to assess the genetic distance between the Fuhuasheng variety and its derivative cultivars.A total of 39 SSR polymorphism primers were used,and 151 bands were obtained,with an average of 2.04 bands in each primer.The genetic SSR-based distance (GD) values ranged from 0.02 to 0.81,while the COP-based GD ranged from 0.25 to 0.98.Certain Fuhuasheng loci displayed higher transmission rates.These loci or nearby chromosomal regions might be associated with desirable traits in Fuhuasheng variety,thus being frequently selected in breeding programs.Therefore,it can be suggested that COP analysis should be the preferred method for estimating genetic diversity invarieties with available complete pedigree information and parents.In this case,marker analysis would provide the best estimations.

Development of eSSR-Markers in Setaria italica and Their Applicability in Studying Genetic Diversity, Cross-Transferability and Comparative Mapping in Millet and Non-Millet Species.

Directory of Open Access Journals (Sweden)

Kajal Kumari

Full Text Available Foxtail millet (Setariaitalica L. is a tractable experimental model crop for studying functional genomics of millets and bioenergy grasses. But the limited availability of genomic resources, particularly expressed sequence-based genic markers is significantly impeding its genetic improvement. Considering this, we attempted to develop EST-derived-SSR (eSSR markers and utilize them in germplasm characterization, cross-genera transferability and in silico comparative mapping. From 66,027 foxtail millet EST sequences 24,828 non-redundant ESTs were deduced, representing ~16 Mb, which revealed 534 (~2% eSSRs in 495 SSR containing ESTs at a frequency of 1/30 kb. A total of 447 pp were successfully designed, of which 327 were mapped physically onto nine chromosomes. About 106 selected primer pairs representing the foxtail millet genome showed high-level of cross-genera amplification at an average of ~88% in eight millets and four non-millet species. Broad range of genetic diversity (0.02-0.65 obtained in constructed phylogenetic tree using 40 eSSR markers demonstrated its utility in germplasm characterizations and phylogenetics. Comparative mapping of physically mapped eSSR markers showed considerable proportion of sequence-based orthology and syntenic relationship between foxtail millet chromosomes and sorghum (~68%, maize (~61% and rice (~42% chromosomes. Synteny analysis of eSSRs of foxtail millet, rice, maize and sorghum suggested the nested chromosome fusion frequently observed in grass genomes. Thus, for the first time we had generated large-scale eSSR markers in foxtail millet and demonstrated their utility in germplasm characterization, transferability, phylogenetics and comparative mapping studies in millets and bioenergy grass species.

Extrapolative microRNA precursor based SSR mining from tea EST database in respect to agronomic traits.

Science.gov (United States)

Hazra, Anjan; Dasgupta, Nirjhar; Sengupta, Chandan; Das, Sauren

2017-07-06

Tea (Camellia sinensis, (L.) Kuntze) is considered as most popular drink across the world and it is widely consumed beverage for its several health-benefit characteristics. These positive traits primarily rely on its regulatory networks of different metabolic pathways. Development of microsatellite markers from the conserved genomic regions are being worthwhile for reviewing the genetic diversity of closely related species or self-pollinated species. Although several SSR markers have been reported, in tea, the trait-specific Simple Sequence Repeat (SSR) markers, leading to be useful in marker assisted breeding technique, are yet to be identified. Micro RNAs are short, non-coding RNA molecules, involved in post transcriptional mode of gene regulation and thus effects on related phenotype. Present study deals with identification of the microsatellite motifs within the reported and predicted miRNA precursors that are effectively followed by designing of primers from SSR flanking regions in order to PCR validation. In addition to the earlier reports, two new miRNAs are predicting here from tea expressed tag sequence database. Furthermore, 18 SSR motifs are found to be in 13 of all 33 predicted miRNAs. Trinucleotide motifs are most abundant among all followed by dinucleotides. Since, miRNA based SSR markers are evidenced to have significant role on genetic fingerprinting study, these outcomes would pave the way in developing novel markers for tagging tea specific agronomic traits as well as substantiating non-conventional breeding program.

Assessment of Functional EST-SSR Markers (Sugarcane in Cross-Species Transferability, Genetic Diversity among Poaceae Plants, and Bulk Segregation Analysis

Directory of Open Access Journals (Sweden)

Shamshad Ul Haq

2016-01-01

Full Text Available Expressed sequence tags (ESTs are important resource for gene discovery, gene expression and its regulation, molecular marker development, and comparative genomics. We procured 10000 ESTs and analyzed 267 EST-SSRs markers through computational approach. The average density was one SSR/10.45 kb or 6.4% frequency, wherein trinucleotide repeats (66.74% were the most abundant followed by di- (26.10%, tetra- (4.67%, penta- (1.5%, and hexanucleotide (1.2% repeats. Functional annotations were done and after-effect newly developed 63 EST-SSRs were used for cross transferability, genetic diversity, and bulk segregation analysis (BSA. Out of 63 EST-SSRs, 42 markers were identified owing to their expansion genetics across 20 different plants which amplified 519 alleles at 180 loci with an average of 2.88 alleles/locus and the polymorphic information content (PIC ranged from 0.51 to 0.93 with an average of 0.83. The cross transferability ranged from 25% for wheat to 97.22% for Schlerostachya, with an average of 55.86%, and genetic relationships were established based on diversification among them. Moreover, 10 EST-SSRs were recognized as important markers between bulks of pooled DNA of sugarcane cultivars through BSA. This study highlights the employability of the markers in transferability, genetic diversity in grass species, and distinguished sugarcane bulks.

Characterization of genetic diversity in chickpea using SSR markers, Start Codon Targeted Polymorphism (SCoT) and Conserved DNA-Derived Polymorphism (CDDP).

Science.gov (United States)

Hajibarat, Zahra; Saidi, Abbas; Hajibarat, Zohreh; Talebi, Reza

2015-07-01

To evaluate the genetic diversity among 48 genotypes of chickpea comprising cultivars, landraces and internationally developed improved lines genetic distances were evaluated using three different molecular marker techniques: Simple Sequence Repeat (SSR); Start Codon Targeted (SCoT) and Conserved DNA-derived Polymorphism (CDDP). Average polymorphism information content (PIC) for SSR, SCoT and CDDP markers was 0.47, 0.45 and 0.45, respectively, and this revealed that three different marker types were equal for the assessment of diversity amongst genotypes. Cluster analysis for SSR and SCoT divided the genotypes in to three distinct clusters and using CDDP markers data, genotypes grouped in to five clusters. There were positive significant correlation (r = 0.43, P SSR markers. These results suggest that efficiency of SSR, SCOT and CDDP markers was relatively the same in fingerprinting of chickpea genotypes. To our knowledge, this is the first detailed report of using targeted DNA region molecular marker (CDDP) for genetic diversity analysis in chickpea in comparison with SCoT and SSR markers. Overall, our results are able to prove the suitability of SCoT and CDDP markers for genetic diversity analysis in chickpea for their high rates of polymorphism and their potential for genome diversity and germplasm conservation.

Development of 23 novel polymorphic EST-SSR markers for the endangered relict conifer Metasequoia glyptostroboides1

Science.gov (United States)

Jin, Yuqing; Bi, Quanxin; Guan, Wenbin; Mao, Jian-Feng

2015-01-01

Premise of the study: Metasequoia glyptostroboides is an endangered relict conifer species endemic to China. In this study, expressed sequence tag–simple sequence repeat (EST-SSR) markers were developed using transcriptome mining for future genetic and functional studies. Methods and Results: We collected 97,565 unigene sequences generated by 454 pyrosequencing. A bioinformatics analysis identified 2087 unique and putative microsatellites, from which 96 novel microsatellite markers were developed. Fifty-three of the 96 primer sets successfully amplified clear fragments of the expected sizes; 23 of those loci were polymorphic. The number of alleles per locus ranged from two to eight, with an average of three, and the observed and expected heterozygosity values ranged from 0 to 1.0 and 0.117 to 0.813, respectively. Conclusions: These microsatellite loci will enrich the genetic resources to develop functional studies and conservation strategies for this endangered relict species. PMID:26421250

In silico comparative analysis of EST-SSRs in three cotton genomes ...

African Journals Online (AJOL)

The range of repeat number change in each HG was wider in Gr-Gh. The annotation of the SSR-ESTs showed that more Gene Ontology (GO) items targeted by SSR-ESTs of Ga and Gr than those of Gh. This study gave us new insights into the difference between the three cotton genomes, which will be more helpful to ...

Development and mapping of a public reference set of SSR markers in Lolium perenne L.

NARCIS (Netherlands)

Bach, J.L.; Muylle, H.; Arens, P.F.P.; Andersen, C.H.; Bach Holm, P.; Ghesquiere, M.; Julier, B.; Lubberstedt, T.; Nielsen, K.K.; Riek, de J.; Roldán-Ruiz, I.; Roulund, N.; Taylor, C.; Vosman, B.J.; Barre, P.

2005-01-01

We report on the characterization and mapping of 76 simple sequence repeat (SSR) markers for Lolium perenne. These markers are publicly available or obtained either from genomic libraries enriched for SSR motifs or L. perenne expressed sequence tag (EST) clones. Four L. perenne mapping populations

Genetic variation, population structure and linkage disequilibrium in Switchgrass with ISSR, SCoT and EST-SSR markers.

Science.gov (United States)

Zhang, Yu; Yan, Haidong; Jiang, Xiaomei; Wang, Xiaoli; Huang, Linkai; Xu, Bin; Zhang, Xinquan; Zhang, Lexin

2016-01-01

To evaluate genetic variation, population structure, and the extent of linkage disequilibrium (LD), 134 switchgrass ( Panicum virgatum L.) samples were analyzed with 51 markers, including 16 ISSRs, 20 SCoTs, and 15 EST-SSRs. In this study, a high level of genetic variation was observed in the switchgrass samples and they had an average Nei's gene diversity index (H) of 0.311. A total of 793 bands were obtained, of which 708 (89.28 %) were polymorphic. Using a parameter marker index (MI), the efficiency of the three types of markers (ISSR, SCoT, and EST-SSR) in the study were compared and we found that SCoT had a higher marker efficiency than the other two markers. The 134 switchgrass samples could be divided into two sub-populations based on STRUCTURE, UPGMA clustering, and principal coordinate analyses (PCA), and upland and lowland ecotypes could be separated by UPGMA clustering and PCA analyses. Linkage disequilibrium analysis revealed an average r 2 of 0.035 across all 51 markers, indicating a trend of higher LD in sub-population 2 than that in sub-population 1 ( P  < 0.01). The population structure revealed in this study will guide the design of future association studies using these switchgrass samples.

Kmer-SSR: a fast and exhaustive SSR search algorithm.

Science.gov (United States)

Pickett, Brandon D; Miller, Justin B; Ridge, Perry G

2017-12-15

One of the main challenges with bioinformatics software is that the size and complexity of datasets necessitate trading speed for accuracy, or completeness. To combat this problem of computational complexity, a plethora of heuristic algorithms have arisen that report a 'good enough' solution to biological questions. However, in instances such as Simple Sequence Repeats (SSRs), a 'good enough' solution may not accurately portray results in population genetics, phylogenetics and forensics, which require accurate SSRs to calculate intra- and inter-species interactions. We present Kmer-SSR, which finds all SSRs faster than most heuristic SSR identification algorithms in a parallelized, easy-to-use manner. The exhaustive Kmer-SSR option has 100% precision and 100% recall and accurately identifies every SSR of any specified length. To identify more biologically pertinent SSRs, we also developed several filters that allow users to easily view a subset of SSRs based on user input. Kmer-SSR, coupled with the filter options, accurately and intuitively identifies SSRs quickly and in a more user-friendly manner than any other SSR identification algorithm. The source code is freely available on GitHub at https://github.com/ridgelab/Kmer-SSR. perry.ridge@byu.edu. © The Author(s) 2017. Published by Oxford University Press.

Development of EST-derived markers in Dendrobium from EST of related taxa

OpenAIRE

Narisa Juejun; Chataporn Chunwongse; Julapark Chunwongse

2013-01-01

Public databases are useful for molecular marker development. The major aim of this study was to develop expressedsequence tag (EST)-derived markers in Dendrobium from available ESTs of Phalaenopsis and Dendrobium. A total of 6063sequences were screened for simple sequence repeats (SSRs) and introns. Primers flanking these regions were generated andtested on genomic DNAs of Phalaenopsis and Dendrobium. Twenty-three percent of amplifiable Phalaenopsis EST-derivedmarkers were cross-genera trans...

Mining and gene ontology based annotation of SSR markers from expressed sequence tags of Humulus lupulus

Science.gov (United States)

Singh, Swati; Gupta, Sanchita; Mani, Ashutosh; Chaturvedi, Anoop

2012-01-01

Humulus lupulus is commonly known as hops, a member of the family moraceae. Currently many projects are underway leading to the accumulation of voluminous genomic and expressed sequence tag sequences in public databases. The genetically characterized domains in these databases are limited due to non-availability of reliable molecular markers. The large data of EST sequences are available in hops. The simple sequence repeat markers extracted from EST data are used as molecular markers for genetic characterization, in the present study. 25,495 EST sequences were examined and assembled to get full-length sequences. Maximum frequency distribution was shown by mononucleotide SSR motifs i.e. 60.44% in contig and 62.16% in singleton where as minimum frequency are observed for hexanucleotide SSR in contig (0.09%) and pentanucleotide SSR in singletons (0.12%). Maximum trinucleotide motifs code for Glutamic acid (GAA) while AT/TA were the most frequent repeat of dinucleotide SSRs. Flanking primer pairs were designed in-silico for the SSR containing sequences. Functional categorization of SSRs containing sequences was done through gene ontology terms like biological process, cellular component and molecular function. PMID:22368382

Transferability of simple sequence repeat (SSR) markers developed in guava (Psidium guajava L.) to four Myrtaceae species.

Science.gov (United States)

Rai, Manoj K; Phulwaria, Mahendra; Shekhawat, N S

2013-08-01

Present study demonstrated the cross-genera transferability of 23 simple sequence repeat (SSR) primer pairs developed for guava (Psidium guajava L.) to four new targets, two species of eucalypts (Eucalyptus citriodora, Eucalyptus camaldulensis), bottlebrush (Callistemon lanceolatus) and clove (Syzygium aromaticum), belonging to the family Myrtaceae and subfamily Myrtoideae. Off the 23 SSR loci assayed, 18 (78.2%) gave cross-amplification in E. citriodora, 14 (60.8%) in E. camaldulensis and 17-17 (73.9%) in C. lanceolatus and S. aromaticum. Eight primer pairs were found to be transferable to all four species. The number of alleles detected at each locus ranged from one to nine, with an average of 4.8, 2.6, 4.5 and 4.6 alleles in E. citriodora, E. camaldulensis, C. lanceolatus and S. aromaticum, respectively. The high levels of cross-genera transferability of guava SSRs may be applicable for the analysis of intra- and inter specific genetic diversity of target species, especially in E. citriodora, C. lanceolatus and S. aromaticum, for which till date no information about EST-derived as well as genomic SSR is available.

Development of genomic SSR markers for fingerprinting lettuce (Lactuca sativa L.) cultivars and mapping genes.

Science.gov (United States)

Rauscher, Gilda; Simko, Ivan

2013-01-22

Lettuce (Lactuca sativa L.) is the major crop from the group of leafy vegetables. Several types of molecular markers were developed that are effectively used in lettuce breeding and genetic studies. However only a very limited number of microsattelite-based markers are publicly available. We have employed the method of enriched microsatellite libraries to develop 97 genomic SSR markers. Testing of newly developed markers on a set of 36 Lactuca accession (33 L. sativa, and one of each L. serriola L., L. saligna L., and L. virosa L.) revealed that both the genetic heterozygosity (UHe = 0.56) and the number of loci per SSR (Na = 5.50) are significantly higher for genomic SSR markers than for previously developed EST-based SSR markers (UHe = 0.32, Na = 3.56). Fifty-four genomic SSR markers were placed on the molecular linkage map of lettuce. Distribution of markers in the genome appeared to be random, with the exception of possible cluster on linkage group 6. Any combination of 32 genomic SSRs was able to distinguish genotypes of all 36 accessions. Fourteen of newly developed SSR markers originate from fragments with high sequence similarity to resistance gene candidates (RGCs) and RGC pseudogenes. Analysis of molecular variance (AMOVA) of L. sativa accessions showed that approximately 3% of genetic diversity was within accessions, 79% among accessions, and 18% among horticultural types. The newly developed genomic SSR markers were added to the pool of previously developed EST-SSRs markers. These two types of SSR-based markers provide useful tools for lettuce cultivar fingerprinting, development of integrated molecular linkage maps, and mapping of genes.

Development of genic SSR markers from transcriptome sequencing of pear buds.

Science.gov (United States)

Yue, Xiao-yan; Liu, Guo-qin; Zong, Yu; Teng, Yuan-wen; Cai, Dan-ying

2014-04-01

A total of 8375 genic simple sequence repeat (SSR) loci were discovered from a unigene set assembled from 116282 transcriptomic unigenes in this study. Dinucleotide repeat motifs were the most common with a frequency of 65.11%, followed by trinucleotide (32.81%). A total of 4100 primer pairs were designed from the SSR loci. Of these, 343 primer pairs (repeat length ≥15 bp) were synthesized with an M13 tail and tested for stable amplification and polymorphism in four Pyrus accessions. After the preliminary test, 104 polymorphic genic SSR markers were developed; dinucleotide and trinucleotide repeats represented 97.11% (101) of these. Twenty-eight polymorphic genic SSR markers were selected randomly to further validate genetic diversity among 28 Pyrus accessions. These markers displayed a high level of polymorphism. The number of alleles at these SSR loci ranged from 2 to 17, with a mean of 9.43 alleles per locus, and the polymorphism information content (PIC) values ranged from 0.26 to 0.91. The UPGMA (unweighted pair-group method with arithmetic average) cluster analysis grouped the 28 Pyrus accessions into two groups: Oriental pears and Occidental pears, which are congruent to the traditional taxonomy, demonstrating their effectiveness in analyzing Pyrus phylogenetic relationships, enriching rare Pyrus EST-SSR resources, and confirming the potential value of a pear transcriptome database for the development of new SSR markers.

Characterization and Development of EST-SSRs by Deep Transcriptome Sequencing in Chinese Cabbage (Brassica rapa L. ssp. pekinensis

Directory of Open Access Journals (Sweden)

Qian Ding

2015-01-01

Full Text Available Simple sequence repeats (SSRs are among the most important markers for population analysis and have been widely used in plant genetic mapping and molecular breeding. Expressed sequence tag-SSR (EST-SSR markers, located in the coding regions, are potentially more efficient for QTL mapping, gene targeting, and marker-assisted breeding. In this study, we investigated 51,694 nonredundant unigenes, assembled from clean reads from deep transcriptome sequencing with a Solexa/Illumina platform, for identification and development of EST-SSRs in Chinese cabbage. In total, 10,420 EST-SSRs with over 12 bp were identified and characterized, among which 2744 EST-SSRs are new and 2317 are known ones showing polymorphism with previously reported SSRs. A total of 7877 PCR primer pairs for 1561 EST-SSR loci were designed, and primer pairs for twenty-four EST-SSRs were selected for primer evaluation. In nineteen EST-SSR loci (79.2%, amplicons were successfully generated with high quality. Seventeen (89.5% showed polymorphism in twenty-four cultivars of Chinese cabbage. The polymorphic alleles of each polymorphic locus were sequenced, and the results showed that most polymorphisms were due to variations of SSR repeat motifs. The EST-SSRs identified and characterized in this study have important implications for developing new tools for genetics and molecular breeding in Chinese cabbage.

Development of unigene-derived SSR markers in cowpea (Vigna unguiculata) and their transferability to other Vigna species.

Science.gov (United States)

Gupta, S K; Gopalakrishna, T

2010-07-01

Unigene sequences available in public databases provide a cost-effective and valuable source for the development of molecular markers. In this study, the identification and development of unigene-based SSR markers in cowpea (Vigna unguiculata (L.) Walp.) is presented. A total of 1071 SSRs were identified in 15 740 cowpea unigene sequences downloaded from the National Center for Biotechnology Information. The most frequent SSR motifs present in the unigenes were trinucleotides (59.7%), followed by dinucleotides (34.8%), pentanucleotides (4%), and tetranucleotides (1.5%). The copy number varied from 6 to 33 for dinucleotide, 5 to 29 for trinucleotide, 5 to 7 for tetranucleotide, and 4 to 6 for pentanucleotide repeats. Primer pairs were successfully designed for 803 SSR motifs and 102 SSR markers were finally characterized and validated. Putative function was assigned to 64.7% of the unigene SSR markers based on significant homology to reported proteins. About 31.7% of the SSRs were present in coding sequences and 68.3% in untranslated regions of the genes. About 87% of the SSRs located in the coding sequences were trinucleotide repeats. Allelic variation at 32 SSR loci produced 98 alleles in 20 cowpea genotypes. The polymorphic information content for the SSR markers varied from 0.10 to 0.83 with an average of 0.53. These unigene SSR markers showed a high rate of transferability (88%) across other Vigna species, thereby expanding their utility. Alignment of unigene sequences with soybean genomic sequences revealed the presence of introns in amplified products of some of the SSR markers. This study presents the distribution of SSRs in the expressed portion of the cowpea genome and is the first report of the development of functional unigene-based SSR markers in cowpea. These SSR markers would play an important role in molecular mapping, comparative genomics, and marker-assisted selection strategies in cowpea and other Vigna species.

Development of EST-derived markers in Dendrobium from EST of related taxa

Directory of Open Access Journals (Sweden)

Narisa Juejun

2013-04-01

Full Text Available Public databases are useful for molecular marker development. The major aim of this study was to develop expressedsequence tag (EST-derived markers in Dendrobium from available ESTs of Phalaenopsis and Dendrobium. A total of 6063sequences were screened for simple sequence repeats (SSRs and introns. Primers flanking these regions were generated andtested on genomic DNAs of Phalaenopsis and Dendrobium. Twenty-three percent of amplifiable Phalaenopsis EST-derivedmarkers were cross-genera transferable to Dendrobium. Forty-one markers from both Phalaenopsis and Dendrobium thatamplified in Dendrobium were assessed on six commercial cultivars and six wild accessions. All of them were transferableamong Dendrobium species. High polymorphism and heterozygosity were observed within wild accessions. Sixteen polymorphic markers were evaluated for linkage analysis on an F1 segregating population. Seven markers were mapped into threelinkage groups, two of which showed syntenic relationship between dendrobium and rice. This relationship will facilitatefurther quantitative trait loci (QTL mapping and comparative genomic studies of Dendrobium. Our results indicate thatPhalaenopsis EST-derived markers are valuable tools for genetic research and breeding applications in Dendrobium.

76 FR 68243 - Social Security Rulings, SSR 91-1c and SSR 66-18c; Rescission of Social Security Rulings (SSR) 66...

Science.gov (United States)

2011-11-03

..., Social Security Online, at http://www.socialsecurity.gov . SUPPLEMENTARY INFORMATION: SSRs make available... SOCIAL SECURITY ADMINISTRATION [Docket No. SSA-2011-0068] Social Security Rulings, SSR 91-1c and SSR 66-18c; Rescission of Social Security Rulings (SSR) 66-18c and SSR 91-1c AGENCY: Social Security...

Development and Testing of New Gene-Homologous EST-SSRs for Eucalyptus gomphocephala (Myrtaceae

Directory of Open Access Journals (Sweden)

Donna Bradbury

2013-07-01

Full Text Available Premise of the study: New microsatellite (simple sequence repeat [SSR] primers were developed from Eucalyptus expressed sequence tags (ESTs and optimized for genetic studies of the southwestern Australian tree E. gomphocephala, which is severely impacted by tree health decline and habitat fragmentation. Methods and Results: A total of 133 gene-homologous EST-SSR primer pairs were designed for Eucalyptus, and 44 were screened in E. gomphocephala. Of these, 17 produced reliable amplification products and 11 were polymorphic. Between two and 13 alleles were observed per locus, and observed heterozygosities ranged from 0.172 to 0.867. All 17 EST-SSRs that amplified E. gomphocephala cross-amplified to at least one of E. marginata, E. camaldulensis, and E. victrix. Conclusions: This set of EST-SSR primer pairs will be valuable tools for future population genetic studies of E. gomphocephala and other eucalypts, particularly for studying gene-linked variation and informing seed-sourcing strategies for ecological restoration.

Population structure and genetic diversity characterization of a sunflower association mapping population using SSR and SNP markers.

Science.gov (United States)

Filippi, Carla V; Aguirre, Natalia; Rivas, Juan G; Zubrzycki, Jeremias; Puebla, Andrea; Cordes, Diego; Moreno, Maria V; Fusari, Corina M; Alvarez, Daniel; Heinz, Ruth A; Hopp, Horacio E; Paniego, Norma B; Lia, Veronica V

2015-02-13

Argentina has a long tradition of sunflower breeding, and its germplasm is a valuable genetic resource worldwide. However, knowledge of the genetic constitution and variability levels of the Argentinean germplasm is still scarce, rendering the global map of cultivated sunflower diversity incomplete. In this study, 42 microsatellite loci and 384 single nucleotide polymorphisms (SNPs) were used to characterize the first association mapping population used for quantitative trait loci mapping in sunflower, along with a selection of allied open-pollinated and composite populations from the germplasm bank of the National Institute of Agricultural Technology of Argentina. The ability of different kinds of markers to assess genetic diversity and population structure was also evaluated. The analysis of polymorphism in the set of sunflower accessions studied here showed that both the microsatellites and SNP markers were informative for germplasm characterization, although to different extents. In general, the estimates of genetic variability were moderate. The average genetic diversity, as quantified by the expected heterozygosity, was 0.52 for SSR loci and 0.29 for SNPs. Within SSR markers, those derived from non-coding regions were able to capture higher levels of diversity than EST-SSR. A significant correlation was found between SSR and SNP- based genetic distances among accessions. Bayesian and multivariate methods were used to infer population structure. Evidence for the existence of three different genetic groups was found consistently across data sets (i.e., SSR, SNP and SSR + SNP), with the maintainer/restorer status being the most prevalent characteristic associated with group delimitation. The present study constitutes the first report comparing the performance of SSR and SNP markers for population genetics analysis in cultivated sunflower. We show that the SSR and SNP panels examined here, either used separately or in conjunction, allowed consistent

Exploiting transcriptome data for the development and characterization of gene-based SSR markers related to cold tolerance in oil palm (Elaeis guineensis).

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Xiao, Yong; Zhou, Lixia; Xia, Wei; Mason, Annaliese S; Yang, Yaodong; Ma, Zilong; Peng, Ming

2014-12-19

The oil palm (Elaeis guineensis, 2n = 32) has the highest oil yield of any crop species, as well as comprising the richest dietary source of provitamin A. For the tropical species, the best mean growth temperature is about 27°C, with a minimal growth temperature of 15°C. Hence, the plantation area is limited into the geographical ranges of 10°N to 10°S. Enhancing cold tolerance capability will increase the total cultivation area and subsequently oil productivity of this tropical species. Developing molecular markers related to cold tolerance would be helpful for molecular breeding of cold tolerant Elaeis guineensis. In total, 5791 gene-based SSRs were identified in 51,452 expressed sequences from Elaeis guineensis transcriptome data: approximately one SSR was detected per 10 expressed sequences. Of these 5791 gene-based SSRs, 916 were derived from expressed sequences up- or down-regulated at least two-fold in response to cold stress. A total of 182 polymorphic markers were developed and characterized from 442 primer pairs flanking these cold-responsive SSR repeats. The polymorphic information content (PIC) of these polymorphic SSR markers across 24 lines of Elaeis guineensis varied from 0.08 to 0.65 (mean = 0.31 ± 0.12). Using in-silico mapping, 137 (75.3%) of the 182 polymorphic SSR markers were located onto the 16 Elaeis guineensis chromosomes. Total coverage of 473 Mbp was achieved, with an average physical distance of 3.4 Mbp between adjacent markers (range 96 bp - 20.8 Mbp). Meanwhile, Comparative analysis of transcriptome under cold stress revealed that one ICE1 putative ortholog, five CBF putative orthologs, 19 NAC transcription factors and four cold-induced orhologs were up-regulated at least two fold in response to cold stress. Interestingly, 5' untranslated region of both Unigene21287 (ICE1) and CL2628.Contig1 (NAC) both contained an SSR markers. In the present study, a series of SSR markers were developed based on sequences

Analysis of SSR information in EST resources of sugarcane

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Expressed sequence tags ( ESTs) offer the opportunity to exploit single, low -copy, conserved sequence motifs for the development of simple sequence repeats ( SSRs). The total of 262 113 ESTs of sugarcane (Saccharum officinarum) in the database of NCBI were downloaded and analyzed, which resulted in...

Cultivar identification and genetic relationship of pineapple (Ananas comosus) cultivars using SSR markers.

Science.gov (United States)

Lin, Y S; Kuan, C S; Weng, I S; Tsai, C C

2015-11-25

The genetic relationships among 27 pineapple [Ananas comosus (L.) Merr.] cultivars and lines were examined using 16 simple sequence repeat (SSR) markers. The number of alleles per locus of the SSR markers ranged from 2 to 6 (average 3.19), for a total of 51 alleles. Similarity coefficients were calculated on the basis of 51 amplified bands. A dendrogram was created according to the 16 SSR markers by the unweighted pair-group method. The banding patterns obtained from the SSR primers allowed most of the cultivars and lines to be distinguished, with the exception of vegetative clones. According to the dendrogram, the 27 pineapple cultivars and lines were clustered into three main clusters and four individual clusters. As expected, the dendrogram showed that derived cultivars and lines are closely related to their parental cultivars; the genetic relationships between pineapple cultivars agree with the genealogy of their breeding history. In addition, the analysis showed that there is no obvious correlation between SSR markers and morphological characters. In conclusion, SSR analysis is an efficient method for pineapple cultivar identification and can offer valuable informative characters to identify pineapple cultivars in Taiwan.

Improvement of SSR core design for ABWR-II

International Nuclear Information System (INIS)

Moriwaki, Masanao; Aoyama, Motoo; Okada, Hiroyuki; Kitamura, Hideya; Sakurada, Koichi; Tanabe, Akira

2003-01-01

In order to enhance the spectral shift effect in the ABWR-II reactor, a novel core design to bring out better performance of spectral shift rods (SSRs) is studied. The SSR is a new type of water rod, in which the water level develops naturally during operation and changes according to the coolant flow rate through the channel. By using the SSR, the average moderator density, which is directly related to core reactivity, can be controlled over a wide range by the core flow rate. In the new SSR core design, two types of SSR bundles, in which settings for the SSR water levels are different, are utilized and loaded according to flow distribution in the core. This two-region SSR core design allows wide variation in the average SSR water level, thus improving fuel economy. Enhancement of SSR function in the two-region SSR core increases the uranium saving factor by about 25%, from the 6% of the conventional uniform SSR core to about 8%. (author)

SSR and morphological trait based population structure analysis of 130 diverse flax (Linum usitatissimum L.) accessions.

Science.gov (United States)

Choudhary, Shashi Bhushan; Sharma, Hariom Kumar; Kumar, Arroju Anil; Maruthi, Rangappa Thimmaiah; Mitra, Jiban; Chowdhury, Isholeena; Singh, Binay Kumar; Karmakar, Pran Gobinda

2017-02-01

A total of 130 flax accessions of diverse morphotypes and worldwide origin were assessed for genetic diversity and population structure using 11 morphological traits and microsatellite markers (15 gSSRs and 7 EST-SSRs). Analysis performed after classifying these accessions on the basis of plant height, branching pattern, seed size, Indian/foreign origin into six categories called sub-populations viz. fibre type exotic, fibre type indigenous, intermediate type exotic, intermediate type indigenous, linseed type exotic and linseed type indigenous. The study assessed different diversity indices, AMOVA, population structure and included a principal coordinate analysis based on different marker systems. The highest diversity was exhibited by gSSR markers (SI=0.46; He=0.31; P=85.11). AMOVA based on all markers explained significant difference among fibre type, intermediate type and linseed type populations of flax. In terms of variation explained by different markers, EST-SSR markers (12%) better differentiated flax populations compared to morphological (9%) and gSSR (6%) markers at P=0.01. The maximum Nei's unbiased genetic distance (D=0.11) was observed between fibre type and linseed type exotic sub-populations based on EST-SSR markers. The combined structure analysis by using all markers grouped Indian fibre type accessions (63.4%) in a separate cluster along with the Indian intermediate type (48.7%), whereas Indian accessions (82.16%) of linseed type constituted an independent cluster. These findings were supported by the results of the principal coordinate analysis. Morphological markers employed in the study found complementary with microsatellite based markers in deciphering genetic diversity and population structure of the flax germplasm. Copyright © 2016 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

The use of sequence-based SSR mining for the development of a vast collection of microsatellites in Aquilegia Formosa

Science.gov (United States)

Brandon Schlautman; Vera Pfeiffer; Juan Zalapa; Johanne Brunet

2014-01-01

Numerous microsatellite markers were developed for Aquilegia formosafrom sequences deposited within the Expressed Sequence Tag (EST), Genomic Survey Sequence (GSS), and Nucleotide databases in NCBI. Microsatellites (SSRs) were identified and primers were designed for 9 SSR containing sequences in the Nucleotide database, 3803 sequences in the EST...

SA-SSR: a suffix array-based algorithm for exhaustive and efficient SSR discovery in large genetic sequences.

Science.gov (United States)

Pickett, B D; Karlinsey, S M; Penrod, C E; Cormier, M J; Ebbert, M T W; Shiozawa, D K; Whipple, C J; Ridge, P G

2016-09-01

Simple Sequence Repeats (SSRs) are used to address a variety of research questions in a variety of fields (e.g. population genetics, phylogenetics, forensics, etc.), due to their high mutability within and between species. Here, we present an innovative algorithm, SA-SSR, based on suffix and longest common prefix arrays for efficiently detecting SSRs in large sets of sequences. Existing SSR detection applications are hampered by one or more limitations (i.e. speed, accuracy, ease-of-use, etc.). Our algorithm addresses these challenges while being the most comprehensive and correct SSR detection software available. SA-SSR is 100% accurate and detected >1000 more SSRs than the second best algorithm, while offering greater control to the user than any existing software. SA-SSR is freely available at http://github.com/ridgelab/SA-SSR CONTACT: perry.ridge@byu.edu Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press.

Novel expressed sequence tag- simple sequence repeats (EST ...

African Journals Online (AJOL)

Using different bioinformatic criteria, the SUCEST database was used to mine for simple sequence repeat (SSR) markers. Among 42,189 clusters, 1,425 expressed sequence tag- simple sequence repeats (EST-SSRs) were identified in silico. Trinucleotide repeats were the most abundant SSRs detected. Of 212 primer pairs ...

DNA Profiles of MTG (Moderat Tahan Gano) Oil Palm Variety Based on SSR Marker

Science.gov (United States)

Putri, L. A. P.; Setiado, H.; Hardianti, R.

2017-03-01

The oil palm, an economically important tree in Indonesia, has been one of the world’s major sources of edible oil and a significant precursor of biodiesel fuel. The objectives of this study were to know DNA profile of commercial MTG (Moderat Tahan Gano) oil palm variety collections. A total of 10 trees MTG oil palm variety were used for analysis. In this experiment, the DNA profile diversity was assessed using mEgCIR0174 and SSR-1 loci of oil palm’s specific SSR markers. The results of the experiment indicated out of 3 alleles of pcr product of mEgCIR0174 (198, 203 and 208 bp) and SSR-1 (201, 217 and 232 bp). These preliminary results demonstrated SSR marker can be used to evaluate genetic relatedness among trees of MTG (Moderat Tahan Gano) oil palm variety derived from different crossing or difference to desease resistance trait or misslabeled.

EST-SSR

African Journals Online (AJOL)

user2

2013-02-27

Feb 27, 2013 ... Due to their high abundance, multi- allelic nature ... different root colors and origins, and 10 related species in Brassica were selected for ... analysis and transferability study, genomic DNA of two radish advanced inbred ...

An online conserved SSR discovery through cross-species comparison

Directory of Open Access Journals (Sweden)

Tun-Wen Pai

2009-02-01

Full Text Available Tun-Wen Pai1, Chien-Ming Chen1, Meng-Chang Hsiao1, Ronshan Cheng2, Wen-Shyong Tzou3, Chin-Hua Hu31Department of Computer Science and Engineering; 2Department of Aquaculture, 3Institute of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung, Taiwan, Republic of ChinaAbstract: Simple sequence repeats (SSRs play important roles in gene regulation and genome evolution. Although there exist several online resources for SSR mining, most of them only extract general SSR patterns without providing functional information. Here, an online search tool, CG-SSR (Comparative Genomics SSR discovery, has been developed for discovering potential functional SSRs from vertebrate genomes through cross-species comparison. In addition to revealing SSR candidates in conserved regions among various species, it also combines accurate coordinate and functional genomics information. CG-SSR is the first comprehensive and efficient online tool for conserved SSR discovery.Keywords: microsatellites, genome, comparative genomics, functional SSR, gene ontology, conserved region

DNA Fingerprinting Eastern Redbud Cultivars (Cercis canadensis) Using SSR Markers

Science.gov (United States)

In this study we present data for a subset of SSR loci, 76 out of the 130 high-quality loci, which were selected out of hundreds of SSR loci identified from a SSR-enriched library. SSR markers are abundant in eukaryotic genomes and are highly reproducible. Previously, we have used SSR markers to e...

FullSSR: Microsatellite Finder and Primer Designer

Directory of Open Access Journals (Sweden)

Sebastián Metz

2016-01-01

Full Text Available Microsatellites are genomic sequences comprised of tandem repeats of short nucleotide motifs widely used as molecular markers in population genetics. FullSSR is a new bioinformatic tool for microsatellite (SSR loci detection and primer design using genomic data from NGS assay. The software was tested with 2000 sequences of Oryza sativa shotgun sequencing project from the National Center of Biotechnology Information Trace Archive and with partial genome sequencing with ROCHE 454® from Caiman latirostris, Salvator merianae, Aegla platensis, and Zilchiopsis collastinensis. FullSSR performance was compared against other similar SSR search programs. The results of the use of this kind of approach depend on the parameters set by the user. In addition, results can be affected by the analyzed sequences because of differences among the genomes. FullSSR simplifies the detection of SSRs and primer design on a big data set. The command line interface of FullSSR was intended to be used as part of genomic analysis tools pipeline; however, it can be used as a stand-alone program because the results are easily interpreted for a nonexpert user.

Identification of SSR and RAPD markers associated with QTLs of ...

African Journals Online (AJOL)

Because of importance of winter survival in winter type of Brassica napus, this study was performed to identify the QTLs controlling winter survival and related traits using SSR and RAPD markers. For this, an F2:3 population of 200 families derived from crossing between cv. 'SLMO46' (winter type and cold resistant) and cv.

Characterization and compilation of polymorphic simple sequence repeat (SSR markers of peanut from public database

Directory of Open Access Journals (Sweden)

Zhao Yongli

2012-07-01

Full Text Available Abstract Background There are several reports describing thousands of SSR markers in the peanut (Arachis hypogaea L. genome. There is a need to integrate various research reports of peanut DNA polymorphism into a single platform. Further, because of lack of uniformity in the labeling of these markers across the publications, there is some confusion on the identities of many markers. We describe below an effort to develop a central comprehensive database of polymorphic SSR markers in peanut. Findings We compiled 1,343 SSR markers as detecting polymorphism (14.5% within a total of 9,274 markers. Amongst all polymorphic SSRs examined, we found that AG motif (36.5% was the most abundant followed by AAG (12.1%, AAT (10.9%, and AT (10.3%.The mean length of SSR repeats in dinucleotide SSRs was significantly longer than that in trinucleotide SSRs. Dinucleotide SSRs showed higher polymorphism frequency for genomic SSRs when compared to trinucleotide SSRs, while for EST-SSRs, the frequency of polymorphic SSRs was higher in trinucleotide SSRs than in dinucleotide SSRs. The correlation of the length of SSR and the frequency of polymorphism revealed that the frequency of polymorphism was decreased as motif repeat number increased. Conclusions The assembled polymorphic SSRs would enhance the density of the existing genetic maps of peanut, which could also be a useful source of DNA markers suitable for high-throughput QTL mapping and marker-assisted selection in peanut improvement and thus would be of value to breeders.

[SSR loci information analysis in transcriptome of Andrographis paniculata].

Science.gov (United States)

Li, Jun-Ren; Chen, Xiu-Zhen; Tang, Xiao-Ting; He, Rui; Zhan, Ruo-Ting

2018-06-01

To study the SSR loci information and develop molecular markers, a total of 43 683 Unigenes in transcriptome of Andrographis paniculata were used to explore SSR. The distribution frequency of SSR and the basic characteristics of repeat motifs were analyzed using MicroSAtellite software, SSR primers were designed by Primer 3.0 software and then validated by PCR. Moreover, the gene function analysis of SSR Unigene was obtained by Blast. The results showed that 14 135 SSR loci were found in the transcriptome of A. paniculata, which distributed in 9 973 Unigenes with a distribution frequency of 32.36%. Di-nucleotide and Tri-nucleotide repeat were the main types, accounted for 75.54% of all SSRs. The repeat motifs of AT/AT and CCG/CGG were the predominant repeat types of Di-nucleotide and Tri-nucleotide, respectively. A total of 4 740 pairs of SSR primers with the potential to produce polymorphism were designed for maker development. Ten pairs of primers in 20 pairs of randomly picked primers produced fragments with expected molecular size. The gene function of Unigenes containing SSR were mostly related to the basic metabolism function of A. paniculata. The SSR markers in transcriptome of A. paniculata show rich type, strong specificity and high potential of polymorphism, which will benefit the candidate gene mining and marker-assisted breeding. Copyright© by the Chinese Pharmaceutical Association.

Construction of an SSR and RAD-Marker Based Molecular Linkage Map of Vigna vexillata (L.) A. Rich.

Science.gov (United States)

Marubodee, Rusama; Ogiso-Tanaka, Eri; Isemura, Takehisa; Chankaew, Sompong; Kaga, Akito; Naito, Ken; Ehara, Hiroshi; Tomooka, Norihiko

2015-01-01

Vigna vexillata (L.) A. Rich. (tuber cowpea) is an underutilized crop for consuming its tuber and mature seeds. Wild form of V. vexillata is a pan-tropical perennial herbaceous plant which has been used by local people as a food. Wild V. vexillata has also been considered as useful gene(s) source for V. unguiculata (cowpea), since it was reported to have various resistance gene(s) for insects and diseases of cowpea. To exploit the potential of V. vexillata, an SSR-based linkage map of V. vexillata was developed. A total of 874 SSR markers successfully amplified single DNA fragment in V. vexillata among 1,336 SSR markers developed from Vigna angularis (azuki bean), V. unguiculata and Phaseolus vulgaris (common bean). An F2 population of 300 plants derived from a cross between salt resistant (V1) and susceptible (V5) accessions was used for mapping. A genetic linkage map was constructed using 82 polymorphic SSR markers loci, which could be assigned to 11 linkage groups spanning 511.5 cM in length with a mean distance of 7.2 cM between adjacent markers. To develop higher density molecular linkage map and to confirm SSR markers position in a linkage map, RAD markers were developed and a combined SSR and RAD markers linkage map of V. vexillata was constructed. A total of 559 (84 SSR and 475 RAD) markers loci could be assigned to 11 linkage groups spanning 973.9 cM in length with a mean distance of 1.8 cM between adjacent markers. Linkage and genetic position of all SSR markers in an SSR linkage map were confirmed. When an SSR genetic linkage map of V. vexillata was compared with those of V. radiata and V. unguiculata, it was suggested that the structure of V. vexillata chromosome was considerably differentiated. This map is the first SSR and RAD marker-based V. vexillata linkage map which can be used for the mapping of useful traits.

Development of Genome-Wide SSR Markers from Angelica gigas Nakai Using Next Generation Sequencing.

Science.gov (United States)

Gil, Jinsu; Um, Yurry; Kim, Serim; Kim, Ok Tae; Koo, Sung Cheol; Reddy, Chinreddy Subramanyam; Kim, Seong-Cheol; Hong, Chang Pyo; Park, Sin-Gi; Kim, Ho Bang; Lee, Dong Hoon; Jeong, Byung-Hoon; Chung, Jong-Wook; Lee, Yi

2017-09-21

Angelica gigas Nakai is an important medicinal herb, widely utilized in Asian countries especially in Korea, Japan, and China. Although it is a vital medicinal herb, the lack of sequencing data and efficient molecular markers has limited the application of a genetic approach for horticultural improvements. Simple sequence repeats (SSRs) are universally accepted molecular markers for population structure study. In this study, we found over 130,000 SSRs, ranging from di- to deca-nucleotide motifs, using the genome sequence of Manchu variety (MV) of A. gigas, derived from next generation sequencing (NGS). From the putative SSR regions identified, a total of 16,496 primer sets were successfully designed. Among them, we selected 848 SSR markers that showed polymorphism from in silico analysis and contained tri- to hexa-nucleotide motifs. We tested 36 SSR primer sets for polymorphism in 16 A. gigas accessions. The average polymorphism information content (PIC) was 0.69; the average observed heterozygosity ( H O ) values, and the expected heterozygosity ( H E ) values were 0.53 and 0.73, respectively. These newly developed SSR markers would be useful tools for molecular genetics, genotype identification, genetic mapping, molecular breeding, and studying species relationships of the Angelica genus.

(SSR) markers

African Journals Online (AJOL)

acer

2013-06-26

Jun 26, 2013 ... analysis was in general agreement with PCoA in discrimi- nating the cultivars. Conclusions. Estimation of morphological diversity may provide addi- tional information on the present finding. Nonetheless, the 29 SSR markers provided considerable genetic reso- lution and this genetic diversity analysis ...

(SSR) markers

African Journals Online (AJOL)

SAM

2014-07-30

Jul 30, 2014 ... India and the country is currently the leading producer, consumer and exporter of ... registration with the competent authority for plant variety protection. Conventionally ... detection of duplicates, parental verification in crosses, gene tagging in .... allelic patterns as revealed by the current set of SSR markers.

Segregation analysis of microsatellite (SSR) markers in sugarcane polyploids.

Science.gov (United States)

Lu, X; Zhou, H; Pan, Y-B; Chen, C Y; Zhu, J R; Chen, P H; Li, Y-R; Cai, Q; Chen, R K

2015-12-28

No information is available on segregation analysis of DNA markers involving both pollen and self-progeny. Therefore, we used capillary electrophoresis- and fluorescence-based DNA fingerprinting together with single pollen collection and polymerase chain reaction (PCR) to investigate simple sequence repeat (SSR) marker segregation among 964 single pollens and 288 self-progenies (S1) of sugarcane cultivar LCP 85-384. Twenty SSR DNA fragments (alleles) were amplified by five polymorphic SSR markers. Only one non-parental SSR allele was observed in 2392 PCRs. SSR allele inheritance was in accordance with Mendelian laws of segregation and independent assortment. Highly significant correlation coefficients were found between frequencies of observed and expected genotypes in pollen and S1 populations. Within the S1 population, the most frequent genotype of each SSR marker was the parental genotype of the same marker. The number of genotypes was higher in pollen than S1 population. PIC values of the five SSR markers were greater in pollen than S1 populations. Eleven of 20 SSR alleles (55%) were segregated in accordance with Mendelian segregation ratios expected from pollen and S1 populations of a 2n = 10x polyploid. Six of 20 SSR alleles were segregated in a 3:1 (presence:absence) ratio and were simplex markers. Four and one alleles were segregated in 77:4 and 143:1 ratios and considered duplex and triplex markers, respectively. Segregation ratios of remaining alleles were unexplainable. The results provide information about selection of crossing parents, estimation of seedling population optimal size, and promotion of efficient selection, which may be valuable for sugarcane breeders.

An RNA Sequencing Transcriptome Analysis of Grasspea (Lathyrus sativus L.) and Development of SSR and KASP Markers.

Science.gov (United States)

Hao, Xiaopeng; Yang, Tao; Liu, Rong; Hu, Jinguo; Yao, Yang; Burlyaeva, Marina; Wang, Yan; Ren, Guixing; Zhang, Hongyan; Wang, Dong; Chang, Jianwu; Zong, Xuxiao

2017-01-01

Grasspea ( Lathyrus sativus L., 2n = 14) has great agronomic potential because of its ability to survive under extreme conditions, such as drought and flood. However, this legume is less investigated because of its sparse genomic resources and very slow breeding process. In this study, 570 million quality-filtered and trimmed cDNA sequence reads with total length of over 82 billion bp were obtained using the Illumina NextSeq TM 500 platform. Approximately two million contigs and 142,053 transcripts were assembled from our RNA-Seq data, which resulted in 27,431 unigenes with an average length of 1,250 bp and maximum length of 48,515 bp. The unigenes were of high-quality. For example, the stay-green (SGR) gene of grasspea was aligned with the SGR gene of pea with high similarity. Among these unigenes, 3,204 EST-SSR primers were designed, 284 of which were randomly chosen for validation. Of these validated unigenes, 87 (30.6%) EST-SSR primers produced polymorphic amplicons among 43 grasspea accessions selected from different geographical locations. Meanwhile, 146,406 SNPs were screened and 50 SNP loci were randomly chosen for the kompetitive allele-specific PCR (KASP) validation. Over 80% (42) SNP loci were successfully transformed to KASP markers. Comparison of the dendrograms according to the SSR and KASP markers showed that the different marker systems are partially consistent with the dendrogram constructed in our study.

Comparison of SSR and SNP markers in estimation of genetic diversity and population structure of Indian rice varieties.

Science.gov (United States)

Singh, Nivedita; Choudhury, Debjani Roy; Singh, Amit Kumar; Kumar, Sundeep; Srinivasan, Kalyani; Tyagi, R K; Singh, N K; Singh, Rakesh

2013-01-01

Simple sequence repeat (SSR) and Single Nucleotide Polymorphic (SNP), the two most robust markers for identifying rice varieties were compared for assessment of genetic diversity and population structure. Total 375 varieties of rice from various regions of India archived at the Indian National GeneBank, NBPGR, New Delhi, were analyzed using thirty six genetic markers, each of hypervariable SSR (HvSSR) and SNP which were distributed across 12 rice chromosomes. A total of 80 alleles were amplified with the SSR markers with an average of 2.22 alleles per locus whereas, 72 alleles were amplified with SNP markers. Polymorphic information content (PIC) values for HvSSR ranged from 0.04 to 0.5 with an average of 0.25. In the case of SNP markers, PIC values ranged from 0.03 to 0.37 with an average of 0.23. Genetic relatedness among the varieties was studied; utilizing an unrooted tree all the genotypes were grouped into three major clusters with both SSR and SNP markers. Analysis of molecular variance (AMOVA) indicated that maximum diversity was partitioned between and within individual level but not between populations. Principal coordinate analysis (PCoA) with SSR markers showed that genotypes were uniformly distributed across the two axes with 13.33% of cumulative variation whereas, in case of SNP markers varieties were grouped into three broad groups across two axes with 45.20% of cumulative variation. Population structure were tested using K values from 1 to 20, but there was no clear population structure, therefore Ln(PD) derived Δk was plotted against the K to determine the number of populations. In case of SSR maximum Δk was at K=5 whereas, in case of SNP maximum Δk was found at K=15, suggesting that resolution of population was higher with SNP markers, but SSR were more efficient for diversity analysis.

Next-Generation Sequencing of the Chrysanthemum nankingense (Asteraceae) Transcriptome Permits Large-Scale Unigene Assembly and SSR Marker Discovery

Science.gov (United States)

Wang, Haibin; Jiang, Jiafu; Chen, Sumei; Qi, Xiangyu; Peng, Hui; Li, Pirui; Song, Aiping; Guan, Zhiyong; Fang, Weimin; Liao, Yuan; Chen, Fadi

2013-01-01

Background Simple sequence repeats (SSRs) are ubiquitous in eukaryotic genomes. Chrysanthemum is one of the largest genera in the Asteraceae family. Only few Chrysanthemum expressed sequence tag (EST) sequences have been acquired to date, so the number of available EST-SSR markers is very low. Methodology/Principal Findings Illumina paired-end sequencing technology produced over 53 million sequencing reads from C. nankingense mRNA. The subsequent de novo assembly yielded 70,895 unigenes, of which 45,789 (64.59%) unigenes showed similarity to the sequences in NCBI database. Out of 45,789 sequences, 107 have hits to the Chrysanthemum Nr protein database; 679 and 277 sequences have hits to the database of Helianthus and Lactuca species, respectively. MISA software identified a large number of putative EST-SSRs, allowing 1,788 primer pairs to be designed from the de novo transcriptome sequence and a further 363 from archival EST sequence. Among 100 primer pairs randomly chosen, 81 markers have amplicons and 20 are polymorphic for genotypes analysis in Chrysanthemum. The results showed that most (but not all) of the assays were transferable across species and that they exposed a significant amount of allelic diversity. Conclusions/Significance SSR markers acquired by transcriptome sequencing are potentially useful for marker-assisted breeding and genetic analysis in the genus Chrysanthemum and its related genera. PMID:23626799

Generation and application of SSR markers in avocado

International Nuclear Information System (INIS)

Sharon, D.; Lavi, U.; Cregan, P.B.; Hillel, J.

1998-01-01

Simple Sequence Repeat (SSR) DNA markers were generated and applied to avocado. An SSR marker is based on a pair of primers which are synthesized on the basis of DNA sequences flanking a micro satellite. These markers are PCR based, quite polymorphic and abundant in several species. These are the markers, of choice in the human genome. The number of SSR markers in the avocado genome was calculated to be about 45,000, with the A/T micro satellite being the most frequent (1 in 40 kb). SSR markers are quite expensive to generate due to the required multi-step procedure; Screening a genomic library, about 66% of the positive clones turned out after sequencing to be SSR containing clones. In only about 55% of these, was it possible to synthesize primers and, of this group, only about 50% of the markers were useful for typing a specific family. Typing of five avocado cultivars using 59 SSR markers results in one to eight alleles per locus, mean heterozygosity ranging between 0.51 and 0.66 and gene diversity ranging between 0.42 and 0.66. The SSR markers were used to estimate the genetic relationships between various Persea species. The number of alleles in these species ranged between five and twelve with heterozygosity levels between 0.11-0.78 and gene diversity between 0.69-0.89. A preliminary genetic map, based on these SSR markers together with some DNA fingerprints (DFP) and randomly amplified polymorphic DNA (RAPD) markers, was drawn. The map consists of 12 linkage group having two to five markers each. Linkage analysis with several quantitative trait loci (QTLs) was performed by genetic typing and phenotypic assessment of the progeny of a controlled cross. The results of the interval mapping suggest that the gene(s) coding for the existence of fibers in the flesh, are probably linked to linkage group 3. (author)

Generation and application of SSR markers in avocado

Energy Technology Data Exchange (ETDEWEB)

Sharon, D; Lavi, U [Institute of Horticulture, ARO Volcani Center, Bet-Dagan (Israel); Cregan, P B [United States Department of Agriculture, Agricultural Research Service, Beltsville, Maryland (United States); Hillel, J [Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot (Israel)

1998-10-01

Simple Sequence Repeat (SSR) DNA markers were generated and applied to avocado. An SSR marker is based on a pair of primers which are synthesized on the basis of DNA sequences flanking a micro satellite. These markers are PCR based, quite polymorphic and abundant in several species. These are the markers, of choice in the human genome. The number of SSR markers in the avocado genome was calculated to be about 45,000, with the A/T micro satellite being the most frequent (1 in 40 kb). SSR markers are quite expensive to generate due to the required multi-step procedure; Screening a genomic library, about 66% of the positive clones turned out after sequencing to be SSR containing clones. In only about 55% of these, was it possible to synthesize primers and, of this group, only about 50% of the markers were useful for typing a specific family. Typing of five avocado cultivars using 59 SSR markers results in one to eight alleles per locus, mean heterozygosity ranging between 0.51 and 0.66 and gene diversity ranging between 0.42 and 0.66. The SSR markers were used to estimate the genetic relationships between various Persea species. The number of alleles in these species ranged between five and twelve with heterozygosity levels between 0.11-0.78 and gene diversity between 0.69-0.89. A preliminary genetic map, based on these SSR markers together with some DNA fingerprints (DFP) and randomly amplified polymorphic DNA (RAPD) markers, was drawn. The map consists of 12 linkage group having two to five markers each. Linkage analysis with several quantitative trait loci (QTLs) was performed by genetic typing and phenotypic assessment of the progeny of a controlled cross. The results of the interval mapping suggest that the gene(s) coding for the existence of fibers in the flesh, are probably linked to linkage group 3. (author) 20 refs, 3 figs, 8 tabs

Transcriptome-derived evidence supports recent polyploidization and a major phylogeographic division in Trithuria submersa (Hydatellaceae, Nymphaeales).

Science.gov (United States)

Marques, Isabel; Montgomery, Sean A; Barker, Michael S; Macfarlane, Terry D; Conran, John G; Catalán, Pilar; Rieseberg, Loren H; Rudall, Paula J; Graham, Sean W

2016-04-01

Relatively little is known about species-level genetic diversity in flowering plants outside the eudicots and monocots, and it is often unclear how to interpret genetic patterns in lineages with whole-genome duplications. We addressed these issues in a polyploid representative of Hydatellaceae, part of the water-lily order Nymphaeales. We examined a transcriptome of Trithuria submersa for evidence of recent whole-genome duplication, and applied transcriptome-derived microsatellite (expressed-sequence tag simple-sequence repeat (EST-SSR)) primers to survey genetic variation in populations across its range in mainland Australia. A transcriptome-based Ks plot revealed at least one recent polyploidization event, consistent with fixed heterozygous genotypes representing underlying sets of homeologous loci. A strong genetic division coincides with a trans-Nullarbor biogeographic boundary. Patterns of 'allelic' variation (no more than two variants per EST-SSR genotype) and recently published chromosomal evidence are consistent with the predicted polyploidization event and substantial homozygosity underlying fixed heterozygote SSR genotypes, which in turn reflect a selfing mating system. The Nullarbor Plain is a barrier to gene flow between two deep lineages of T. submersa that may represent cryptic species. The markers developed here should also be useful for further disentangling species relationships, and provide a first step towards future genomic studies in Trithuria. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

SSR markers: a tool for species identification in Psidium (Myrtaceae).

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Tuler, A C; Carrijo, T T; Nóia, L R; Ferreira, A; Peixoto, A L; da Silva Ferreira, M F

2015-11-01

Molecular DNA markers are used for detection of polymorphisms in individuals. As they are independent of developmental stage of the plant and environmental influences, they can be useful tools in taxonomy. The alleles of simple sequence repeat (SSR) markers (or microsatellites) are traditionally used to identify taxonomic units. This application demands the laborious and costly delimitation of exclusive alleles in order to avoid homoplasy. Here, we propose a method for identification of species based on the amplification profile of groups of SSR markers obtained by a transferability study. The approach considers that the SSR are conserved among related species. In this context, using Psidium as a model, 141 SSR markers developed for Psidium guajava were transferred to 13 indigenous species of Psidium from the Atlantic Rainforest. Transferability of the markers was high and 28 SSR were conserved in all species. Four SSR groups were defined and they can help in the identification of all 13 Psidium species studied. A group of 31 SSR was genotyped, with one to six alleles each. The H0 varied from 0.0 to 0.46, and PIC from 0.0 to 0.74. Cluster analysis revealed shared alleles among species. The high percentage of SSR transferability found in Psidium evidences the narrow phylogenetic relationship existing among these species since transferability occurs by the preservation of the microsatellites and anchoring regions. The proposed method was useful for distinguishing the species of Psidium, being useful in taxonomic studies.

Comparison of SSR and SNP markers in estimation of genetic diversity and population structure of Indian rice varieties.

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Nivedita Singh

Full Text Available Simple sequence repeat (SSR and Single Nucleotide Polymorphic (SNP, the two most robust markers for identifying rice varieties were compared for assessment of genetic diversity and population structure. Total 375 varieties of rice from various regions of India archived at the Indian National GeneBank, NBPGR, New Delhi, were analyzed using thirty six genetic markers, each of hypervariable SSR (HvSSR and SNP which were distributed across 12 rice chromosomes. A total of 80 alleles were amplified with the SSR markers with an average of 2.22 alleles per locus whereas, 72 alleles were amplified with SNP markers. Polymorphic information content (PIC values for HvSSR ranged from 0.04 to 0.5 with an average of 0.25. In the case of SNP markers, PIC values ranged from 0.03 to 0.37 with an average of 0.23. Genetic relatedness among the varieties was studied; utilizing an unrooted tree all the genotypes were grouped into three major clusters with both SSR and SNP markers. Analysis of molecular variance (AMOVA indicated that maximum diversity was partitioned between and within individual level but not between populations. Principal coordinate analysis (PCoA with SSR markers showed that genotypes were uniformly distributed across the two axes with 13.33% of cumulative variation whereas, in case of SNP markers varieties were grouped into three broad groups across two axes with 45.20% of cumulative variation. Population structure were tested using K values from 1 to 20, but there was no clear population structure, therefore Ln(PD derived Δk was plotted against the K to determine the number of populations. In case of SSR maximum Δk was at K=5 whereas, in case of SNP maximum Δk was found at K=15, suggesting that resolution of population was higher with SNP markers, but SSR were more efficient for diversity analysis.

Development of SSR markers and construction of a linkage map in jute

Indian Academy of Sciences (India)

We recently initiated a programme to develop simple sequence repeat markers and reported a set of 2469 SSR that were developed using four SSR-enriched libraries (Mir et al. 2009). In this communication, we report an additional set of 607 novel SSR in 393 SSR containing sequences. However, primers could be ...

New device based on the super spatial resolution (SSR) method

International Nuclear Information System (INIS)

Soluri, A.; Atzeni, G.; Ucci, A.; Bellone, T.; Cusanno, F.; Rodilossi, G.; Massari, R.

2013-01-01

Recently it have been described that innovative methods, namely Super Spatial Resolution (SSR), can be used to improve the scintigraphic imaging. The aim of SSR techniques is the enhancement of the resolution of an imaging system, using information from several images. In this paper we describe a new experimental apparatus that could be used for molecular imaging and small animal imaging. In fact we present a new device, completely automated, that uses the SSR method and provides images with better spatial resolution in comparison to the original resolution. Preliminary small animal imaging studies confirm the feasibility of a very high resolution system in scintigraphic imaging and the possibility to have gamma cameras using the SSR method, to perform the applications on functional imaging. -- Highlights: • Super spatial resolution brings a high resolution image from scintigraphic images. • Resolution improvement depends on the signal to noise ratio of the original images. • The SSR shows significant improvement on spatial resolution in scintigraphic images. • The SSR method is potentially utilizable for all scintigraphic devices

Large-scale development of SSR markers in tobacco and construction of a linkage map in flue-cured tobacco.

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Tong, Zhijun; Xiao, Bingguang; Jiao, Fangchan; Fang, Dunhuang; Zeng, Jianmin; Wu, Xingfu; Chen, Xuejun; Yang, Jiankang; Li, Yongping

2016-06-01

Tobacco (Nicotiana tabacum L.), particularly flue-cured tobacco, is one of the most economically important nonfood crops and is also an important model system in plant biotechnology. Despite its importance, only limited molecular marker resources are available for genome analysis, genetic mapping, and breeding. Simple sequence repeats (SSR) are one of the most widely-used molecular markers, having significant advantages including that they are generally co-dominant, easy to use, abundant in eukaryotic organisms, and produce highly reproducible results. In this study, based on the genome sequence data of flue-cured tobacco (K326), we developed a total of 13,645 mostly novel SSR markers, which were working in a set of eighteen tobacco varieties of four different types. A mapping population of 213 backcross (BC1) individuals, which were derived from an intra-type cross between two flue-cured tobacco varieties, Y3 and K326, was selected for mapping. Based on the newly developed SSR markers as well as published SSR markers, we constructed a genetic map consisting of 626 SSR loci distributed across 24 linkage groups and covering a total length of 1120.45 cM with an average distance of 1.79 cM between adjacent markers, which is the highest density map of flue-cured tobacco till date.

Association of AFLP and SSR markers with agronomic and fibre ...

Indian Academy of Sciences (India)

We have attempted to tag yield and fibre quality traits with AFLP and SSR markers using F2 and F3 populations of a cross between two Gossypium hirsutum varieties, PS56-4 and RS2013. Out of 50 AFLP primer combinations and 177 SSR primer pairs tested, 32 AFLP and four SSR primers were chosen for genotyping F2 ...

Reimagining SSR in Contexts of Security Pluralism

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Megan Price

2017-07-01

Full Text Available Within the repertoire of international stabilization interventions, security sector reform (SSR and other conventional efforts to strengthen security and governance institutions remain central. There is increasing recognition that the policies and practices operating under the rubric of SSR are blind to the empirical reality of 'security pluralism' in most stabilization contexts. In these contexts, both security providers directly authorized by the state (police, army and a multitude of other coercive actors engage in producing and reproducing order, and enjoy varying degrees of public authority and legitimacy. Recognizing this, research was undertaken in three cities (Beirut, Nairobi, and Tunis to discern the conditions enabling various security providers to forge constructive relations with local populations and governance actors. Drawing on insights generated by these case studies, this article problematizes conventional state-centric approaches and argues for a bold reimagining of SSR. It makes the case for an SSR approach that prioritizes promoting the accountability and responsiveness of all security providers, integrating efforts to strengthen the social determinants of security, and enabling a phased transition from relational to rules-based systems of security provision and governance.

Transcriptome Sequencing and Development of Genic SSR Markers of an Endangered Chinese Endemic Genus Dipteronia Oliver (Aceraceae).

Science.gov (United States)

Zhou, Tao; Li, Zhong-Hu; Bai, Guo-Qing; Feng, Li; Chen, Chen; Wei, Yue; Chang, Yong-Xia; Zhao, Gui-Fang

2016-02-23

Dipteronia Oliver (Aceraceae) is an endangered Chinese endemic genus consisting of two living species, Dipteronia sinensis and Dipteronia dyeriana. However, studies on the population genetics and evolutionary analyses of Dipteronia have been hindered by limited genomic resources and genetic markers. Here, the generation, de novo assembly and annotation of transcriptome datasets, and a large set of microsatellite or simple sequence repeat (SSR) markers derived from Dipteronia have been described. After Illumina pair-end sequencing, approximately 93.2 million reads were generated and assembled to yield a total of 99,358 unigenes. A majority of these unigenes (53%, 52,789) had at least one blast hit against the public protein databases. Further, 12,377 SSR loci were detected and 4179 primer pairs were designed for experimental validation. Of these 4179 primer pairs, 435 primer pairs were randomly selected to test polymorphism. Our results show that products from 132 primer pairs were polymorphic, in which 97 polymorphic SSR markers were further selected to analyze the genetic diversity of 10 natural populations of Dipteronia. The identification of SSR markers during our research will provide the much valuable data for population genetic analyses and evolutionary studies in Dipteronia.

Genome-Wide Characterization of Simple Sequence Repeat (SSR) Loci in Chinese Jujube and Jujube SSR Primer Transferability

Science.gov (United States)

Xiao, Jing; Zhao, Jin; Liu, Mengjun; Liu, Ping; Dai, Li; Zhao, Zhihui

2015-01-01

Chinese jujube (Ziziphus jujuba), an economically important species in the Rhamnaceae family, is a popular fruit tree in Asia. Here, we surveyed and characterized simple sequence repeats (SSRs) in the jujube genome. A total of 436,676 SSR loci were identified, with an average distance of 0.93 Kb between the loci. A large proportion of the SSRs included mononucleotide, dinucleotide and trinucleotide repeat motifs, which accounted for 64.87%, 24.40%, and 8.74% of all repeats, respectively. Among the mononucleotide repeats, A/T was the most common, whereas AT/TA was the most common dinucleotide repeat. A total of 30,565 primer pairs were successfully designed and screened using a series of criteria. Moreover, 725 of 1,000 randomly selected primer pairs were effective among 6 cultivars, and 511 of these primer pairs were polymorphic. Sequencing the amplicons of two SSRs across three jujube cultivars revealed variations in the repeats. The transferability of jujube SSR primers proved that 35/64 SSRs could be transferred across family boundary. Using jujube SSR primers, clustering analysis results from 15 species were highly consistent with the Angiosperm Phylogeny Group (APGIII) System. The genome-wide characterization of SSRs in Chinese jujube is very valuable for whole-genome characterization and marker-assisted selection in jujube breeding. In addition, the transferability of jujube SSR primers could provide a solid foundation for their further utilization. PMID:26000739

Transcriptomic resources for the medicinal legume Mucuna pruriens: de novo transcriptome assembly, annotation, identification and validation of EST-SSR markers.

Science.gov (United States)

Sathyanarayana, N; Pittala, Ranjith Kumar; Tripathi, Pankaj Kumar; Chopra, Ratan; Singh, Heikham Russiachand; Belamkar, Vikas; Bhardwaj, Pardeep Kumar; Doyle, Jeff J; Egan, Ashley N

2017-05-25

The medicinal legume Mucuna pruriens (L.) DC. has attracted attention worldwide as a source of the anti-Parkinson's drug L-Dopa. It is also a popular green manure cover crop that offers many agronomic benefits including high protein content, nitrogen fixation and soil nutrients. The plant currently lacks genomic resources and there is limited knowledge on gene expression, metabolic pathways, and genetics of secondary metabolite production. Here, we present transcriptomic resources for M. pruriens, including a de novo transcriptome assembly and annotation, as well as differential transcript expression analyses between root, leaf, and pod tissues. We also develop microsatellite markers and analyze genetic diversity and population structure within a set of Indian germplasm accessions. One-hundred ninety-one million two hundred thirty-three thousand two hundred forty-two bp cleaned reads were assembled into 67,561 transcripts with mean length of 626 bp and N50 of 987 bp. Assembled sequences were annotated using BLASTX against public databases with over 80% of transcripts annotated. We identified 7,493 simple sequence repeat (SSR) motifs, including 787 polymorphic repeats between the parents of a mapping population. 134 SSRs from expressed sequenced tags (ESTs) were screened against 23 M. pruriens accessions from India, with 52 EST-SSRs retained after quality control. Population structure analysis using a Bayesian framework implemented in fastSTRUCTURE showed nearly similar groupings as with distance-based (neighbor-joining) and principal component analyses, with most of the accessions clustering per geographical origins. Pair-wise comparison of transcript expression in leaves, roots and pods identified 4,387 differentially expressed transcripts with the highest number occurring between roots and leaves. Differentially expressed transcripts were enriched with transcription factors and transcripts annotated as belonging to secondary metabolite pathways. The M

Development of EST-SSR markers for Elaeocarpus photiniifolia (Elaeocarpaceae), an endemic taxon of the Bonin Islands.

Science.gov (United States)

Sugai, Kyoko; Setsuko, Suzuki; Uchiyama, Kentaro; Murakami, Noriaki; Kato, Hidetoshi; Yoshimaru, Hiroshi

2012-02-01

Expressed sequence tag (EST)-derived microsatellite markers were developed for Elaeocarpus photiniifolia, an endemic taxon of the Bonin Islands. Initially, a complementary DNA (cDNA) library was constructed by de novo pyrosequencing of total RNA extracted from a seedling. A total of 267 primer pairs were designed from the library. Of the 48 tested loci, 25 loci were polymorphic among 41 individuals representing the entire geographical range of the species, with the number of alleles per locus and expected heterozygosity ranging from two to 14 and 0.09 to 0.86, respectively. Most loci were transferable to a related species, E. sylvestris. The developed markers will be useful for evaluating the genetic structure of E. photiniifolia.

Linkage Map of a Gene Controlling Zero Tannins (zt-1 in Faba Bean (Vicia faba L. with SSR and ISSR Markers

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Wanwei Hou

2018-05-01

Full Text Available Faba bean (Vicia faba L., a partially allogamous species, is rich in protein. Condensed tannins limit the use of faba beans as food and feed. Two recessive genes, zt-1 and zt-2, control the zero tannin content in faba bean and promote a white flower phenotype. To determine the inheritance and develop a linkage map for the zt-1 gene in the faba bean germplasm M3290, F2 and F3 progenies were derived from the purple flower and high tannin content genotypes Qinghai12 and zt-1 line M3290, respectively. Genetic analysis verified a single recessive gene for zero tannin content and flower colour. In total, 596 SSR markers and 100 ISSR markers were used to test the polymorphisms between the parents and bulks for the contrasting flower colour via Bulked Segregant Analysis (BSA. Subsequently, six SSR markers and seven ISSR markers were used to genotype the entire 413 F2 population. Linkage analysis showed that the zt-1 gene was closely linked to the SSR markers SSR84 and M78, with genetic distances of 2.9 and 5.8 cM, respectively. The two flanked SSR markers were used to test 34 faba bean genotypes with different flower colours. The closely linked SSR marker SSR84 predicted the zt-1 genotypes with absolute accuracy. The results from the marker-assisted selection (MAS from this study could provide a solid foundation for further faba bean breeding programmes.

SAT, a flexible and optimized Web application for SSR marker development

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Rami Jean-François

2007-11-01

Full Text Available Abstract Background Simple Sequence Repeats (SSRs, or microsatellites, are among the most powerful genetic markers known. A common method for the development of SSR markers is the construction of genomic DNA libraries enriched for SSR sequences, followed by DNA sequencing. However, designing optimal SSR markers from bulk sequence data is a laborious and time-consuming process. Results SAT (SSR Analysis Tool is a user-friendly Web application developed to minimize tedious manual operations and reduce errors. This tool facilitates the integration, analysis and display of sequence data from SSR-enriched libraries. SAT is designed to successively perform base calling and quality evaluation of chromatograms, eliminate cloning vector, adaptors and low quality sequences, detect chimera or partially digested sequences, search for SSR motifs, cluster and assemble the redundant sequences, and design SSR primer pairs. An additional virtual PCR step establishes primer specificity. Users may modify the different parameters of each step of the SAT analysis. Although certain steps are compulsory, such as SSR motifs search and sequence assembly, users do not have to run the entire pipeline, and they can choose selectively which steps to perform. A database allows users to store and query results, and to redo individual steps of the workflow. Conclusion The SAT Web application is available at http://sat.cirad.fr/sat, and a standalone command-line version is also freely downloadable. Users must send an email to the SAT administrator tropgene@cirad.fr to request a login and password.

Development of a set of SSR markers for genetic polymorphism detection and interspecific hybrid jute breeding

Directory of Open Access Journals (Sweden)

Dipnarayan Saha

2017-10-01

Full Text Available Corchorus capsularis (white jute and C. olitorius (dark jute are the two principal cultivated species of jute that produce natural bast fiber of commercial importance. We have identified 4509 simple sequence repeat (SSR loci from 34,163 unigene sequences of C. capsularis to develop a non-redundant set of 2079 flanking primer pairs. Among the SSRs, trinucleotide repeats were most frequent (60% followed by dinucleotide repeats (37.6%. Annotation of the SSR-containing unigenes revealed their putative functions in various biological and molecular processes, including responses to biotic and abiotic signals. Eighteen expressed gene-derived SSR (eSSR markers were successfully mapped to the existing single-nucleotide polymorphism (SNP linkage map of jute, providing additional anchor points. Amplification of 72% of the 74 randomly selected primer pairs was successful in a panel of 24 jute accessions, comprising five and twelve accessions of C. capsularis and C. olitorius, respectively, and seven wild jute species. Forty-three primer pairs produced an average of 2.7 alleles and 58.1% polymorphism in a panel of 24 jute accessions. The mean PIC value was 0.34 but some markers showed PIC values higher than 0.5, suggesting that these markers can efficiently measure genetic diversity and serve for mapping of quantitative trait loci (QTLs in jute. A primer polymorphism survey with parents of a wide-hybridized population between a cultivated jute and its wild relative revealed their efficacy for interspecific hybrid identification. For ready accessibility of jute eSSR primers, we compiled all information in a user-friendly web database, JuteMarkerdb (http://jutemarkerdb.icar.gov.in/ for the first time in jute. This eSSR resource in jute is expected to be of use in characterization of germplasm, interspecific hybrid and variety identification, and marker-assisted breeding of superior-quality jute.

Large-scale development of PIP and SSR markers and their complementary applied in Nicotiana.

Science.gov (United States)

Huang, L; Cao, H; Yang, L; Yu, Yu; Wang, Yu

2013-08-01

PIP (Potential Intron Polymorphism) and SSR (Simple Sequence Repeats) were used in many species, but large-scale development and combined use of these two markers have not been reported in tobacco. In this study, a total of 12,388 PIP and 76,848 SSR markers were designed and uploaded to a web-accessible database (http://yancao.sdau.edu.cn/tgb/). E-PCR analysis showed that PIP and SSR rarely overlapped and were strongly complementary in the tobacco genome. The density was 3.07 PIP and 1.72 SSR markers per 10 kb of the known sequences. A total of 153 and 166 alleles were detectedby 22 PIP and 22 SSR markers in 64 Nicotiana accessions. SSR produced higher PIC (polymorphism information content) values and identified more alleles than PIP, whereas PIP could identify larger numbers of rare alleles. Mantel testing demonstrated a high correlation coefficient (r = 0.949, P SSR. The UPGMA dendrogram created from the combined PIP and SSR markers was clearer and more reliable than the individual PIP or SSR dendrograms. It suggested that PIP and SSR can make up the deficiency of molecular markers not only in tobacco but other plant.

Experiment data report for semiscale Mod-2A primary feed and bleed experiment series (Tests S-SR-1 and S-SR-2)

International Nuclear Information System (INIS)

Fogdall, S.P.

1982-10-01

This report presents test data recorded for Tests S-SR-1 and S-SR-2 of the Semiscale Mod-2A Primary Feed and Bleed Tests. These tests are part of a series of Semiscale tests that investigate the thermal-hydraulic phenomena resulting from a hypothesized loss-of-coolant accident (LOCA) or abnormal operating transient. These tests provide experimental data for assessing the analytical capability of computer codes used in LOCA and operational transient analysis. The primary objectives of Tests S-SR-1 and -2 were to provide data on primary system recovery through the use of primary feed and bleed cooling, with no heat transfer to the secondaries. Data was obtained using high- and low-head pump curves for the safety injection (SI) pumps. This report presents the uninterpreted data from Tests S-SR-1 and -2 for analysis. The data, presented as graphs in engineering units, have been analyzed only to the extent necessary to ensure that they are reasonable and consistent

SSR-CE/FD assessment of Guizhou approved sugarcane cultivars and regional materials

Science.gov (United States)

Twelve sugarcane genotypes (three cultivars and nine clones involved in regional tests) from Guizhou Province, China were analyzed using SSR-capillary electrophoresis/fluorescence detection (SSR-CE/FD) technology to construct the SSR fingerprints and assess the genetic diversity. A total of 131 DNA ...

SSR: Its Effects on Students' Reading Habits after They Complete the Program.

Science.gov (United States)

Wiesendanger, Katherine D.; Bader, Lois

1989-01-01

Studies the effect of sustained silent reading (SSR) on recreational reading habits after termination of instruction. Finds that SSR students read more than those not in the program, and that SSR has no impact on above average readers, great impact on average readers, and little impact on below average readers. (RS)

Development and characterization of genomic SSR markers for Anneslea fragrans (Pentaphylacaceae).

Science.gov (United States)

Sun, Lijing; Meng, Kaikai; Liao, Boyong; Li, Chunmei; Zhang, Yue; Liao, Wenbo; Chen, Sufang

2017-10-01

The genus Anneslea (Pentaphylacaceae) contains four species and six varieties, most of which are locally endemic. Here, simple sequence repeat (SSR) markers were developed for the conservation of these species. The genome of A. fragrans was sequenced and de novo assembled into 445,162 contigs, of which 30,409 SSR loci were detected. Primers for 100 SSR loci were validated with PCR amplification in three populations of A. fragrans . Seventy-nine loci successfully amplified, and 30 were polymorphic. The mean number of alleles, observed heterozygosity, and expected heterozygosity were 7.01 ± 1.60, 0.817 ± 0.241, and 0.796 ± 0.145, respectively. Most primers could be amplified in Ternstroemia gymnanthera , T. kwangtungensis , and Cleyera pachyphylla . Our study demonstrated that shotgun genome sequencing is an efficient way to develop genomic SSR markers for nonmodel species. These genomic SSR loci will be valuable in population genetic studies in Anneslea and its relatives.

On the status of Ukrainian SSR before the beginning of perestroika

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А. А. Омарова

2014-12-01

Full Text Available The article studies legal status of Ukrainian SSR before the beginning of Perestroika. Constitutional acts, laws and other regulatory acts are analyzed which fixed the status of Ukrainian SSR within USSR. On the basis of study of regulatory sources and monographs we came to conclusion that a contradiction existed between legally fixed and actual status of Ukrainian SSR within USSR before the beginning of Perestroika.

Identification, validation and cross-species transferability of novel Lavandula EST-SSRs.

Science.gov (United States)

Adal, Ayelign M; Demissie, Zerihun A; Mahmoud, Soheil S

2015-04-01

We identified and characterized EST-SSRs with strong discrimination power against Lavandula angustifolia and Lavandula x intermedia . The markers also showed considerable cross-species transferability rate into six related Lavandula species. Lavenders (Lavandula) are important economical crops grown around the globe for essential oil production. In an attempt to develop genetic markers for these plants, we analyzed over 13,000 unigenes developed from L. angustifolia and L. x intermedia EST databases, and identified 3,459 simple sequence repeats (SSR), which were dominated by trinucleotides (41.2 %) and dinucleotides (31.45 %). Approximately, 19 % of the unigenes contained at least one SSR marker, over 60 % of which were localized in the UTRs. Only 252 EST-SSRs were 18 bp or longer from which 31 loci were validated, and 24 amplified discrete fragments with 85 % polymorphism in L. x intermedia and L. angustifolia. The average number of alleles in L. x intermedia and L. angustifolia were 3.42 and 3.71 per marker with average PIC values of 0.47 and 0.52, respectively. These values suggest a moderate to strong level of informativeness for the markers, with some loci producing unique fingerprints. The cross-species transferability rate of the markers ranges 50-100 % across eight species. The utility of these markers was assessed in eight Lavandula species and 15 L. angustifolia and L. x intermedia cultivars, and the dendrogram deduced from their similarity indexes successfully delineated the species into their respective sections and the cultivars into their respective species. These markers have potential for application in fingerprinting, diversity studies and marker-assisted breeding of Lavandula.

DNA profiling of pineapple cultivars in Japan discriminated by SSR markers

Science.gov (United States)

Shoda, Moriyuki; Urasaki, Naoya; Sakiyama, Sumisu; Terakami, Shingo; Hosaka, Fumiko; Shigeta, Narumi; Nishitani, Chikako; Yamamoto, Toshiya

2012-01-01

We developed 18 polymorphic simple sequence repeat (SSR) markers in pineapple (Ananas comosus) by using genomic libraries enriched for GA and CA motifs. The markers were used to genotype 31 pineapple accessions, including seven cultivars and 11 breeding lines from Okinawa Prefecture, 12 foreign accessions and one from a related species. These SSR loci were highly polymorphic: the 31 accessions contained three to seven alleles per locus, with an average of 4.1. The values of expected heterozygosity ranged from 0.09 to 0.76, with an average of 0.52. All 31 accessions could be successfully differentiated by the 18 SSR markers, with the exception of ‘N67-10’ and ‘Hawaiian Smooth Cayenne’. A single combination of three markers TsuAC004, TsuAC010 and TsuAC041, was enough to distinguish all accessions with one exception. A phenogram based on the SSR genotypes did not show any distinct groups, but it suggested that pineapples bred in Japan are genetically diversed. We reconfirmed the parentage of 14 pineapple accessions by comparing the SSR alleles at 17 SSR loci in each accession and its reported parents. The obtained information will contribute substantially to protecting plant breeders’ rights. PMID:23341750

De novo comparative transcriptome analysis of genes involved in fruit morphology of pumpkin cultivars with extreme size difference and development of EST-SSR markers.

Science.gov (United States)

Xanthopoulou, Aliki; Ganopoulos, Ioannis; Psomopoulos, Fotis; Manioudaki, Maria; Moysiadis, Theodoros; Kapazoglou, Aliki; Osathanunkul, Maslin; Michailidou, Sofia; Kalivas, Apostolos; Tsaftaris, Athanasios; Nianiou-Obeidat, Irini; Madesis, Panagiotis

2017-07-30

The genetic basis of fruit size and shape was investigated for the first time in Cucurbita species and genetic loci associated with fruit morphology have been identified. Although extensive genomic resources are available at present for tomato (Solanum lycopersicum), cucumber (Cucumis sativus), melon (Cucumis melo) and watermelon (Citrullus lanatus), genomic databases for Cucurbita species are limited. Recently, our group reported the generation of pumpkin (Cucurbita pepo) transcriptome databases from two contrasting cultivars with extreme fruit sizes. In the current study we used these databases to perform comparative transcriptome analysis in order to identify genes with potential roles in fruit morphology and fruit size. Differential Gene Expression (DGE) analysis between cv. 'Munchkin' (small-fruit) and cv. 'Big Moose' (large-fruit) revealed a variety of candidate genes associated with fruit morphology with significant differences in gene expression between the two cultivars. In addition, we have set the framework for generating EST-SSR markers, which discriminate different C. pepo cultivars and show transferability to related Cucurbitaceae species. The results of the present study will contribute to both further understanding the molecular mechanisms regulating fruit morphology and furthermore identifying the factors that determine fruit size. Moreover, they may lead to the development of molecular marker tools for selecting genotypes with desired morphological traits. Copyright © 2017. Published by Elsevier B.V.

simple sequence repeat (SSR)

African Journals Online (AJOL)

In the present study, 78 mapped simple sequence repeat (SSR) markers representing 11 linkage groups of adzuki bean were evaluated for transferability to mungbean and related Vigna spp. 41 markers amplified characteristic bands in at least one Vigna species. The transferability percentage across the genotypes ranged ...

Construction of an integrated genetic linkage map for the A genome of Brassica napus using SSR markers derived from sequenced BACs in B. rapa

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King Graham J

2010-10-01

Full Text Available Abstract Background The Multinational Brassica rapa Genome Sequencing Project (BrGSP has developed valuable genomic resources, including BAC libraries, BAC-end sequences, genetic and physical maps, and seed BAC sequences for Brassica rapa. An integrated linkage map between the amphidiploid B. napus and diploid B. rapa will facilitate the rapid transfer of these valuable resources from B. rapa to B. napus (Oilseed rape, Canola. Results In this study, we identified over 23,000 simple sequence repeats (SSRs from 536 sequenced BACs. 890 SSR markers (designated as BrGMS were developed and used for the construction of an integrated linkage map for the A genome in B. rapa and B. napus. Two hundred and nineteen BrGMS markers were integrated to an existing B. napus linkage map (BnaNZDH. Among these mapped BrGMS markers, 168 were only distributed on the A genome linkage groups (LGs, 18 distrubuted both on the A and C genome LGs, and 33 only distributed on the C genome LGs. Most of the A genome LGs in B. napus were collinear with the homoeologous LGs in B. rapa, although minor inversions or rearrangements occurred on A2 and A9. The mapping of these BAC-specific SSR markers enabled assignment of 161 sequenced B. rapa BACs, as well as the associated BAC contigs to the A genome LGs of B. napus. Conclusion The genetic mapping of SSR markers derived from sequenced BACs in B. rapa enabled direct links to be established between the B. napus linkage map and a B. rapa physical map, and thus the assignment of B. rapa BACs and the associated BAC contigs to the B. napus linkage map. This integrated genetic linkage map will facilitate exploitation of the B. rapa annotated genomic resources for gene tagging and map-based cloning in B. napus, and for comparative analysis of the A genome within Brassica species.

Assessment of Multiple GNSS Real-Time SSR Products from Different Analysis Centers

Directory of Open Access Journals (Sweden)

Zhiyu Wang

2018-03-01

Full Text Available The real-time State Space Representation (SSR product of the GNSS (Global Navigation Satellite System orbit and clock is one of the most essential corrections for real-time precise point positioning (PPP. In this work, the performance of current SSR products from eight analysis centers were assessed by comparing it with the final product and the accuracy of real-time PPP. Numerical results showed that (1 the accuracies of the GPS SSR product were better than 8 cm for the satellite orbit and 0.3 ns for the satellite clock; (2 the accuracies of the GLONASS (GLObalnaya NAvigatsionnaya Sputnikovaya Sistema SSR product were better than 10 cm for orbit RMS (Root Mean Square and 0.6 ns for clock STD (Standard Deviation; and (3 the accuracies of the BDS (BeiDou Navigation Satellite System and Galileo SSR products from CLK93 were about 14.54 and 4.42 cm for the orbit RMS and 0.32 and 0.18 ns for the clock STD, respectively. The simulated kinematic PPP results obtained using the SSR products from CLK93 and CLK51 performed better than those using other SSR products; and the accuracy of PPP based on all products was better than 6 and 10 cm in the horizontal and vertical directions, respectively. The real-time kinematic PPP experiment carried out in Beijing, Tianjin, and Shijiazhuang, China indicated that the SSR product CLK93 from Centre National d’Etudes Spatiales (CNES had a better performance than CAS01. Moreover, the PPP with GPS + BDS dual systems had a higher accuracy than those with only a GPS single system.

Use of EST-SSR Markers for Evaluating Genetic Diversity and Fingerprinting Celery (Apium graveolens L. Cultivars

Directory of Open Access Journals (Sweden)

Nan Fu

2014-02-01

Full Text Available Celery (Apium graveolens L. is one of the most economically important vegetables worldwide, but genetic and genomic resources supporting celery molecular breeding are quite limited, thus few studies on celery have been conducted so far. In this study we made use of simple sequence repeat (SSR markers generated from previous celery transcriptome sequencing and attempted to detect the genetic diversity and relationships of commonly used celery accessions and explore the efficiency of the primers used for cultivars identification. Analysis of molecular variance (AMOVA of Apium graveolens L. var. dulce showed that approximately 43% of genetic diversity was within accessions, 45% among accessions, and 22% among horticultural types. The neighbor-joining tree generated by unweighted pair group method with arithmetic mean (UPGMA, and population structure analysis, as well as principal components analysis (PCA, separated the cultivars into clusters corresponding to the geographical areas where they originated. Genetic distance analysis suggested that genetic variation within Apium graveolens was quite limited. Genotypic diversity showed any combinations of 55 genic SSRs were able to distinguish the genotypes of all 30 accessions.

SSR Analysis of Genetic Diversity Among 192 Diploid Potato Cultivars

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Xiaoyan Song

2016-05-01

Full Text Available In potato breeding, it is difficult to improve the traits of interest at the tetraploid level due to the tetrasomic inheritance. A promising alternative is diploid breeding. Thus it is necessary to assess the genetic diversity of diploid potato germplasm for efficient exploration and deployment of desirable traits. In this study, we used SSR markers to evaluate the genetic diversity of diploid potato cultivars. To screen polymorphic SSR markers, 55 pairs of SSR primers were employed to amplify 39 cultivars with relatively distant genetic relationships. Among them, 12 SSR markers with high polymorphism located at 12 chromosomes were chosen to evaluate the genetic diversity of 192 diploid potato cultivars. The primers produced 6 to 18 bands with an average of 8.2 bands per primer. In total, 98 bands were amplified from 192 cultivars, and 97 of them were polymorphic. Cluster analysis using UPGMA showed the genetic relationships of all accessions tested: 186 of the 192 accessions could be distinguished by only 12 pairs of SSR primers, and the 192 diploid cultivars were divided into 11 groups, and 83.3% constituted the first group. Clustering results showed relatively low genetic diversity among 192 diploid cultivars, with closer relationship at the molecular level. The results can provide molecular basis for diploid potato breeding.

PineElm_SSRdb: a microsatellite marker database identified from genomic, chloroplast, mitochondrial and EST sequences of pineapple (Ananas comosus (L.) Merrill).

Science.gov (United States)

Chaudhary, Sakshi; Mishra, Bharat Kumar; Vivek, Thiruvettai; Magadum, Santoshkumar; Yasin, Jeshima Khan

2016-01-01

Simple Sequence Repeats or microsatellites are resourceful molecular genetic markers. There are only few reports of SSR identification and development in pineapple. Complete genome sequence of pineapple available in the public domain can be used to develop numerous novel SSRs. Therefore, an attempt was made to identify SSRs from genomic, chloroplast, mitochondrial and EST sequences of pineapple which will help in deciphering genetic makeup of its germplasm resources. A total of 359511 SSRs were identified in pineapple (356385 from genome sequence, 45 from chloroplast sequence, 249 in mitochondrial sequence and 2832 from EST sequences). The list of EST-SSR markers and their details are available in the database. PineElm_SSRdb is an open source database available for non-commercial academic purpose at http://app.bioelm.com/ with a mapping tool which can develop circular maps of selected marker set. This database will be of immense use to breeders, researchers and graduates working on Ananas spp. and to others working on cross-species transferability of markers, investigating diversity, mapping and DNA fingerprinting.

In vivo imaging of neuroinflammation in the rodent brain with [{sup 11}C]SSR180575, a novel indoleacetamide radioligand of the translocator protein (18 kDa)

Energy Technology Data Exchange (ETDEWEB)

Chauveau, Fabien [CEA, DSV, IBM, Service Hospitalier Frederic Joliot, Orsay (France); Universite Paris Sud, INSERM U1023, Orsay (France); Universite Lyon 1, Creatis, CNRS UMR 5220, INSERM U630, INSA Lyon, Lyon (France); Boutin, Herve [CEA, DSV, IBM, Service Hospitalier Frederic Joliot, Orsay (France); Universite Paris Sud, INSERM U1023, Orsay (France); University of Manchester, Faculty of Life Sciences, Manchester (United Kingdom); Camp, Nadja van; Tavitian, Bertrand [CEA, DSV, IBM, Service Hospitalier Frederic Joliot, Orsay (France); Universite Paris Sud, INSERM U1023, Orsay (France); Thominiaux, Cyrille; Dolle, Frederic [CEA, DSV, IBM, Service Hospitalier Frederic Joliot, Orsay (France); Hantraye, Philippe [CEA, DSV, IBM, MIRCEN, Fontenay-aux-Roses (France); Rivron, Luc [Sanofi-Aventis, GMPK-Global Isotope Chemistry and Metabolite Synthesis Department (ICMS), Paris (France); Marguet, Frank; Castel, Marie-Noelle; Rooney, Thomas; Benavides, Jesus [Sanofi-Aventis, CNS Department, Paris (France)

2011-03-15

Neuroinflammation is involved in neurological disorders through the activation of microglial cells. Imaging of neuroinflammation with radioligands for the translocator protein (18 kDa) (TSPO) could prove to be an attractive biomarker for disease diagnosis and therapeutic evaluation. The indoleacetamide-derived 7-chloro-N,N,5-trimethyl-4-oxo-3-phenyl-3,5-dihydro-4H-pyridazino[4,5-b]indole-1-acetamide, SSR180575, is a selective high-affinity TSPO ligand in human and rodents with neuroprotective effects. Here we report the radiolabelling of SSR180575 with {sup 11}C and in vitro and in vivo imaging in an acute model of neuroinflammation in rats. The image contrast and the binding of [{sup 11}C]SSR180575 are higher than that obtained with the isoquinoline-based TSPO radioligand, [{sup 11}C]PK11195. Competition studies demonstrate that [{sup 11}C]SSR180575 has high specific binding for the TSPO. [{sup 11}C]SSR180575 is the first PET radioligand for the TSPO based on an indoleacetamide scaffold designed for imaging neuroinflammation in animal models and in the clinic. (orig.)

Arduino Based RFID Line Switching Using SSR

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Michael E.

2017-10-01

Full Text Available The importance of line switching cannot be overemphasized as they are used to connect and disconnect substations to and from a distribution grid. At the cradle of technology line switching was achieved via the use of manual switches or fuses which could endanger life as a result of electrocution when expose during maintenance. This ill prompted the development of automated line switching using relays and contactors. With time this tends to fail as a result of wearing of the contact which is as a result of arcing and low voltage. To avert all these ills this paper presents Arduino based Radio Frequency Identification RFID line switching using Solid State Relay SSR. This is to ensure the safety of operators or technologist and to also avert the problem associated with relays and contactors using SSR. This was achieved using RFID RC-522 reader ardriuno Uno SSR and other discrete components. The system was tested and worked perfectly reducing the risk of electrocution and eliminating damage wearing of the contacts common with contactors and relays.

Transcriptome sequencing of lentil based on second-generation technology permits large-scale unigene assembly and SSR marker discovery

Directory of Open Access Journals (Sweden)

Materne Michael

2011-05-01

Full Text Available Abstract Background Lentil (Lens culinaris Medik. is a cool-season grain legume which provides a rich source of protein for human consumption. In terms of genomic resources, lentil is relatively underdeveloped, in comparison to other Fabaceae species, with limited available data. There is hence a significant need to enhance such resources in order to identify novel genes and alleles for molecular breeding to increase crop productivity and quality. Results Tissue-specific cDNA samples from six distinct lentil genotypes were sequenced using Roche 454 GS-FLX Titanium technology, generating c. 1.38 × 106 expressed sequence tags (ESTs. De novo assembly generated a total of 15,354 contigs and 68,715 singletons. The complete unigene set was sequence-analysed against genome drafts of the model legume species Medicago truncatula and Arabidopsis thaliana to identify 12,639, and 7,476 unique matches, respectively. When compared to the genome of Glycine max, a total of 20,419 unique hits were observed corresponding to c. 31% of the known gene space. A total of 25,592 lentil unigenes were subsequently annoated from GenBank. Simple sequence repeat (SSR-containing ESTs were identified from consensus sequences and a total of 2,393 primer pairs were designed. A subset of 192 EST-SSR markers was screened for validation across a panel 12 cultivated lentil genotypes and one wild relative species. A total of 166 primer pairs obtained successful amplification, of which 47.5% detected genetic polymorphism. Conclusions A substantial collection of ESTs has been developed from sequence analysis of lentil genotypes using second-generation technology, permitting unigene definition across a broad range of functional categories. As well as providing resources for functional genomics studies, the unigene set has permitted significant enhancement of the number of publicly-available molecular genetic markers as tools for improvement of this species.

(SSR) markers for analysis of genetic diversity in African rice ...

African Journals Online (AJOL)

Bonny Oloka

2015-05-06

May 6, 2015 ... and conservation. To address this knowledge gap, 10 highly polymorphic rice simple sequence repeat. (SSR) markers were used to characterize 99 rice genotypes to determine their diversity and place them in their different population groups. The SSR markers were multiplexed in 3 panels to increase their.

Salzburger State Reactance Scale (SSR Scale): Validation of a Scale Measuring State Reactance.

Science.gov (United States)

Sittenthaler, Sandra; Traut-Mattausch, Eva; Steindl, Christina; Jonas, Eva

This paper describes the construction and empirical evaluation of an instrument for measuring state reactance, the Salzburger State Reactance (SSR) Scale. The results of a confirmatory factor analysis supported a hypothesized three-factor structure: experience of reactance, aggressive behavioral intentions, and negative attitudes. Correlations with divergent and convergent measures support the validity of this structure. The SSR Subscales were strongly related to the other state reactance measures. Moreover, the SSR Subscales showed modest positive correlations with trait measures of reactance. The SSR Subscales correlated only slightly or not at all with neighboring constructs (e.g., autonomy, experience of control). The only exception was fairness scales, which showed moderate correlations with the SSR Subscales. Furthermore, a retest analysis confirmed the temporal stability of the scale. Suggestions for further validation of this questionnaire are discussed.

An efficient identification strategy of clonal tea cultivars using long-core motif SSR markers.

Science.gov (United States)

Wang, Rang Jian; Gao, Xiang Feng; Kong, Xiang Rui; Yang, Jun

2016-01-01

Microsatellites, or simple sequence repeats (SSRs), especially those with long-core motifs (tri-, tetra-, penta-, and hexa-nucleotide) represent an excellent tool for DNA fingerprinting. SSRs with long-core motifs are preferred since neighbor alleles are more easily separated and identified from each other, which render the interpretation of electropherograms and the true alleles more reliable. In the present work, with the purpose of characterizing a set of core SSR markers with long-core motifs for well fingerprinting clonal cultivars of tea (Camellia sinensis), we analyzed 66 elite clonal tea cultivars in China with 33 initially-chosen long-core motif SSR markers covering all the 15 linkage groups of tea plant genome. A set of 6 SSR markers were conclusively selected as core SSR markers after further selection. The polymorphic information content (PIC) of the core SSR markers was >0.5, with ≤5 alleles in each marker containing 10 or fewer genotypes. Phylogenetic analysis revealed that the core SSR markers were not strongly correlated with the trait 'cultivar processing-property'. The combined probability of identity (PID) between two random cultivars for the whole set of 6 SSR markers was estimated to be 2.22 × 10(-5), which was quite low, confirmed the usefulness of the proposed SSR markers for fingerprinting analyses in Camellia sinensis. Moreover, for the sake of quickly discriminating the clonal tea cultivars, a cultivar identification diagram (CID) was subsequently established using these core markers, which fully reflected the identification process and provided the immediate information about which SSR markers were needed to identify a cultivar chosen among the tested ones. The results suggested that long-core motif SSR markers used in the investigation contributed to the accurate and efficient identification of the clonal tea cultivars and enabled the protection of intellectual property.

SSRPT (SSR Pointer Trackeer) for Cassini Mission Operations - A Ground Data Analysis Tool

Science.gov (United States)

Kan, E.

1998-01-01

Tracking the resources of the two redundant Solid State Recorders (SSR) is a necessary routine for Cassini spacecraft mission operations. Instead of relying on a full-fledged spacecraft hardware/software simulator to track and predict the SSR recording and playback pointer positions, a stand-alone SSR Pointer Tracker tool was developed as part of JPL's Multimission Spacecraft Analysis system.

Analysis of cold resistance and identification of SSR markers linked to cold resistance genes in Brassica rapa L.

Science.gov (United States)

Huang, Zhen; Zhang, Xuexian; Jiang, Shouhua; Qin, Mengfan; Zhao, Na; Lang, Lina; Liu, Yaping; Tian, Zhengshu; Liu, Xia; Wang, Yang; Zhang, Binbin; Xu, Aixia

2017-06-01

Currently, cold temperatures are one of the main factors threatening rapeseed production worldwide; thus, it is imperative to identify cold-resistant germplasm and to cultivate cold-resistant rapeseed varieties. In this study, the cold resistance of four Brassica rapa varieties was analyzed. The cold resistance of Longyou6 and Longyou7 was better than that of Tianyou2 and Tianyou4. Thus, an F 2 population derived from Longyou6 and Tianyou4 was used to study the correlation of cold resistance and physiological indexes. Our results showed that the degree of frost damage was related to the relative conductivity and MDA content (r1 = 0.558 and r2 = 0.447, respectively). In order to identify the markers related to cold resistance, 504 pairs of SSR (simple sequence repeats) primers were used to screen the two parents and F 2 population. Four and five SSR markers had highly significant positive correlation to relative conductivity and MDA, respectively. In addition, three of these SSR markers had a highly significant positive correlation to both of these two indexes. These three SSR markers were subsequently confirmed to be used to distinguish between cold-resistant and non-cold-resistant varieties. The results of this study will lay a solid foundation for the mapping of cold-resistant genes and molecular markers assisted selection for the cold-resistance.

Expressed sequence tag-derived microsatellite markers of perennial ryegrass (Lolium perenne L.)

DEFF Research Database (Denmark)

Studer, Bruno; Asp, Torben; Frei, Ursula

2008-01-01

An expressed sequence tag (EST) library of the key grassland species perennial ryegrass (Lolium perenne L.) has been exploited as a resource for microsatellite marker development. Out of 955 simple sequence repeat (SSR) containing ESTs, 744 were used for primer design. Primer amplification was te...

SSR-based association mapping of salt tolerance in cotton (Gossypium hirsutum L.).

Science.gov (United States)

Zhao, Y L; Wang, H M; Shao, B X; Chen, W; Guo, Z J; Gong, H Y; Sang, X H; Wang, J J; Ye, W W

2016-05-25

The identification of simple sequence repeat (SSR) markers associated with salt tolerance in cotton contributes to molecular assisted selection (MAS), which can improve the efficiency of traditional breeding. In this study, 134 samples of upland cotton cultivars were selected. The seedling emergence rates were tested under 0.3% NaCl stress. A total of 74 SSR markers were used to scan the genomes of these samples. To identify SSR markers associated with salt tolerance, an association analysis was performed between salt tolerance and SSR markers using TASSEL 2.1, based on the analysis of genetic structure using Structure 2.3.4. The results showed that the seedling emergence rates of 134 cultivars were significantly different, and 27 salt-sensitive and 10 salt-tolerant cultivars were identified. A total of 148 loci were found in 74 SSR markers involving 246 allelic variations, which ranged from 2 to 7 with an average of 3.32 per SSR marker. The gene diversity ranged from 0.0295 to 0.4959, with the average being 0.2897. The polymorphic information content ranged from0.0290 to 0.3729, with the average being 0.2381. This natural population was classified into two subgroups by Structure 2.3.4, containing 89 and 45 samples, respectively. Finally, eight SSR sites associated with salt tolerance ware found through an association analysis, with the rate of explanation ranging from 2.91 to 7.82% and an average of 4.32%. These results provide reference data for the use MAS for salt tolerance in cotton.

Genetic diversity of wild and cultivated genotypes of pigeonpea through RAPD and SSR markers.

Science.gov (United States)

Walunjkar, Babasaheb C; Parihar, Akarsh; Singh, Nirbhay Kumar; Parmar, L D

2015-03-01

Eight wild and four cultivated pigeonpea genotypes were subjected to RAPD and microsatellite analysis, with 40 primers each. Out of these, eight RAPD and five SSR primers were found polymorphic. RAPD primers showed 100% polymorphism and produced a total of 517 DNA fragments, whereas SSR primers produced 67 fragments and they too showed 100% polymorphism. The RAPD markers revealed highest similarity co-efficient of 0.93 (GT-100 and ICPL-87), whereas the highest similarity co-efficient obtained with SSR markers was 1.00 (GTH-1 and GT-100). Average PIC value obtained with RAPD and SSR were 0.90 and 0.18, respectively. The arithmetic mean heterozygosity and marker index were 0.90 and 22.47 respectively with RAPD marker, whereas the corresponding values for SSR markers were 0.18 and 33.66. Moreover; the four wild genotypes (Cajanus scarabaeoides, Rhyncosia rufescence, Cajanus cajanifolius and Rhyncosia canna) and the four cultivars (GTH-1, GT-100, ICPL-87 and GT-1) grouped distinctly in the same subgroups of the dendrograms obtained with both RAPD and SSR analysis. Therefore, the findings of SSR supplement and validate the results obtained with RAPD analysis.

An accurate and efficient method for large-scale SSR genotyping and applications.

Science.gov (United States)

Li, Lun; Fang, Zhiwei; Zhou, Junfei; Chen, Hong; Hu, Zhangfeng; Gao, Lifen; Chen, Lihong; Ren, Sheng; Ma, Hongyu; Lu, Long; Zhang, Weixiong; Peng, Hai

2017-06-02

Accurate and efficient genotyping of simple sequence repeats (SSRs) constitutes the basis of SSRs as an effective genetic marker with various applications. However, the existing methods for SSR genotyping suffer from low sensitivity, low accuracy, low efficiency and high cost. In order to fully exploit the potential of SSRs as genetic marker, we developed a novel method for SSR genotyping, named as AmpSeq-SSR, which combines multiplexing polymerase chain reaction (PCR), targeted deep sequencing and comprehensive analysis. AmpSeq-SSR is able to genotype potentially more than a million SSRs at once using the current sequencing techniques. In the current study, we simultaneously genotyped 3105 SSRs in eight rice varieties, which were further validated experimentally. The results showed that the accuracies of AmpSeq-SSR were nearly 100 and 94% with a single base resolution for homozygous and heterozygous samples, respectively. To demonstrate the power of AmpSeq-SSR, we adopted it in two applications. The first was to construct discriminative fingerprints of the rice varieties using 3105 SSRs, which offer much greater discriminative power than the 48 SSRs commonly used for rice. The second was to map Xa21, a gene that confers persistent resistance to rice bacterial blight. We demonstrated that genome-scale fingerprints of an organism can be efficiently constructed and candidate genes, such as Xa21 in rice, can be accurately and efficiently mapped using an innovative strategy consisting of multiplexing PCR, targeted sequencing and computational analysis. While the work we present focused on rice, AmpSeq-SSR can be readily extended to animals and micro-organisms. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

In vivo imaging of neuro-inflammation in the rodent brain with [11C]SSR180575, a novel indoleacetamide radioligand of the translocator protein (18 kDa)

International Nuclear Information System (INIS)

Chauveau, F.; Boutin, H.; Van Camp, N.; Thominiaux, C.; Dolle, F.; Tavitian, B.; Chauveau, F.; Boutin, H.; Van Camp, N.; Tavitian, B.; Hantraye, P.; Rivron, L.; Marguet, F.; Castel, M.N.; Rooney, T.; Benavides, J.; Chauveau, F.; Boutin, H.

2011-01-01

Purpose Neuro-inflammation is involved in neurological disorders through the activation of micro-glial cells. Imaging of neuro-inflammation with radioligands for the translocator protein (18 kDa) (TSPO) could prove to be an attractive bio-marker for disease diagnosis and therapeutic evaluation. The indoleacetamide-derived 7-chloro-N, N, 5- trimethyl-4-oxo-3-phenyl-3, 5-dihydro-4H-pyridazino[4, 5-b] indole-1-acetamide, SSR180575, is a selective high-affinity TSPO ligand in human and rodents with neuro-protective effects. Methods Here we report the radiolabelling of SSR180575 with 11 C and in vitro and in vivo imaging in an acute model of neuro-inflammation in rats. Results The image contrast and the binding of [ 11 C] SSR180575 are higher than that obtained with the isoquinoline- based TSPO radioligand, [ 11 C]PK11195. Competition studies demonstrate that [ 11 C]SSR180575 has high specific binding for the TSPO. Conclusion [ 11 C]SSR180575 is the first PET radioligand for the TSPO based on an indoleacetamide scaffold designed for imaging neuro-inflammation in animal models and in the clinic. (authors)

The research of SSR which can be restrained by photovoltaic grid connected

Science.gov (United States)

Li, Kuan; Liu, Meng; Zheng, Wei; Li, Yudun; Wang, Xin

2018-02-01

Utilization of photovoltaic power generation has attracted considerable attention, and it is growing rapidly due to its environmental benefits. The series capacitive compensation is needed to be introduced into the lines which could improve the transmission capacity. However, the series capacitive compensation may lead to sub-synchronous resonance(SSR). This paper proposes a method to restrain the SSR based on photovoltaic grid connected which is caused by series capacitive compensation. Sub-synchronous oscillation damping controller (SSDC) is designed based on complex torque coefficient approach, and the SSDC is added to the PV power station’s main controller to damp SSR. IEEE Second benchmark model is used as simulation model based on PSCAD/EMTDC. The results show that the designed SSDC could restrain SSR and improve stability in PV grid connected effectively.

Identification and genetic mapping of highly polymorphic microsatellite loci from an EST database of the septoria tritici blotch pathogen Mycosphaerella graminicola

NARCIS (Netherlands)

Goodwin, S.B.; Lee, van der T.A.J.; Cavaletto, J.R.; Lintel Hekkert, te B.; Crane, C.F.; Kema, G.H.J.

2007-01-01

A database of 30,137 EST sequences from Mycosphaerella graminicola, the septoria tritici blotch fungus of wheat, was scanned with a custom software pipeline for di- and trinucleotide units repeated tandemly six or more times. The bioinformatics analysis identified 109 putative SSR loci, and for 99

Mapping of QTLs for frost tolerance and heading time using SSR ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-19

Oct 19, 2008 ... using SSR markers in bread wheat. Omid Sofalian1*, Seyyed A. ... Key words: Bread wheat, frost tolerance, heading time, QTL mapping, single marker analysis, SSR. INTRODUCTION. Abiotic stresses are crucial ... cultivars are divided into two types (winter and spring growth habit) depending on their need ...

Identification and Validation of EST-Derived Molecular Markers, TRAP and VNTRs, for Banana Research

NARCIS (Netherlands)

Garcia, S.A.L.; Talebi, R.; Ferreira, C.F.; Vroh, B.I.; Paiva, L.V.; Kema, G.H.J.; Souza, M.T.

2011-01-01

The advent of high-throughput sequencing technology has generated abundant information on DNA sequences for the genomes of many plant species. Expressed Sequence Tags (ESTs), which are unique DNA sequences derived from a cDNA library and therefore representing genes transcribed in specific tissues

Development and characterization of genomic SSR markers in Cynodon transvaalensis Burtt-Davy.

Science.gov (United States)

Tan, Chengcheng; Wu, Yanqi; Taliaferro, Charles M; Bell, Greg E; Martin, Dennis L; Smith, Mike W

2014-08-01

Simple sequence repeat (SSR) markers are a major molecular tool for genetic and genomic research that have been extensively developed and used in major crops. However, few are available in African bermudagrass (Cynodon transvaalensis Burtt-Davy), an economically important warm-season turfgrass species. African bermudagrass is mainly used for hybridizations with common bermudagrass [C. dactylon var. dactylon (L.) Pers.] in the development of superior interspecific hybrid turfgrass cultivars. Accordingly, the major objective of this study was to develop and characterize a large set of SSR markers. Genomic DNA of C. transvaalensis '4200TN 24-2' from an Oklahoma State University (OSU) turf nursery was extracted for construction of four SSR genomic libraries enriched with [CA](n), [GA](n), [AAG](n), and [AAT](n) as core repeat motifs. A total of 3,064 clones were sequenced at the OSU core facility. The sequences were categorized into singletons and contiguous sequences to exclude redundancy. From the two sequence categories, 1,795 SSR loci were identified. After excluding duplicate SSRs by comparison with previously developed SSR markers using a nucleotide basic local alignment tool, 1,426 unique primer pairs (PPs) were designed. Out of the 1,426 designed PPs, 981 (68.8 %) amplified alleles of the expected size in the donor DNA. Polymorphisms of the SSR PPs tested in eight C. transvaalensis plants were 93 % polymorphic with 544 markers effective in all genotypes. Inheritance of the SSRs was examined in six F(1) progeny of African parents 'T577' × 'Uganda', indicating 917 markers amplified heritable alleles. The SSR markers developed in the study are the first large set of co-dominant markers in African bermudagrass and should be highly valuable for molecular and traditional breeding research.

Data of 10 SSR markers for genomes of homo sapiens and monkeys.

Science.gov (United States)

Reddy, K K V V V S; Raju, S Viswanadha; Someswara Rao, Chinta

2017-06-01

In this data, we present 10 Simple Sequence Repeat(SSR) markers TAGA, TCAT, GAAT, AGAT, AGAA, GATA, TATC, CTTT, TCTG and TCTA which are extracted from the genomes of homo sapiens and monkeys using string matching mechanism [1]. All loci showed 4 Base Pair(bp) in allele size, indicating that there are some polymorphisms between individuals correlating to the number of SSR repeats that maybe useful for the detection of similarity among the genotypes. Collectively, these data show that the SSR extraction is a valuable method to illustrate genetic variation of genomes.

Identification and characterization of salt responsive miRNA-SSR markers in rice (Oryza sativa).

Science.gov (United States)

Mondal, Tapan Kumar; Ganie, Showkat Ahmad

2014-02-10

Salinity is an important abiotic stress that affects agricultural production and productivity. It is a complex trait that is regulated by different molecular mechanisms. miRNAs are non-coding RNAs which are highly conserved and regulate gene expression. Simple sequence repeats (SSRs) are robust molecular markers for studying genetic diversity. Although several SSR markers are available now, challenge remains to identify the trait-specific SSRs which can be used for marker assisted breeding. In order to understand the genetic diversity of salt responsive-miRNA genes in rice, SSR markers were mined from 130 members of salt-responsive miRNA genes of rice and validated among the contrasting panels of tolerant as well as susceptible rice genotypes, each with 12 genotypes. Although 12 miR-SSRs were found to be polymorphic, only miR172b-SSR was able to differentiate the tolerant and susceptible genotypes in 2 different groups. It had also been found that miRNA genes were more diverse in susceptible genotypes than the tolerant one (as indicated by polymorphic index content) which might interfere to form the stem-loop structure of premature miRNA and their subsequent synthesis in susceptible genotypes. Thus, we concluded that length variations of the repeats in salt responsive miRNA genes may be responsible for a possible sensitivity to salinity adaptation. This is the first report of characterization of trait specific miRNA derived SSRs in plants. Copyright © 2013 Elsevier B.V. All rights reserved.

Cross-species amplification of 105 Lolium perenne SSR loci in 23 species within the Poaceae

DEFF Research Database (Denmark)

Jensen, Louise Bach; Holm, Preben Bach; Lübberstedt, Thomas

2007-01-01

Amplification of 105 Lolium perenne SSR markers was studied in 23 grass species representing seven tribes from three subfamilies of Poaceae. Twelve of the SSR markers are published for the first time. Between 2% and 96% of the SSR markers could be amplified within a given species. A subset of eight...... SSR markers was evaluated for polymorphism across nine of the 23 grass species. Four to seven of the markers were polymorphic within each species, with an average detection of 2.4 alleles per species....

Development of advanced BWR fuel bundle with spectral shift rod (3) -transient analysis of ABWR core with SSR

International Nuclear Information System (INIS)

Ikegawa, T.; Chaki, M.; Ohga, Y.; Abe, M.

2010-01-01

The spectral shift rod (SSR) is a new type of water rod, utilized instead of the conventional water rod, in which a water level develops during core operation. The water level can be changed according to the fuel channel flow rate. In this study, ABWR plant performance with SSR fuel bundles under transient conditions has been evaluated using the TRACG code. The TRACG code, which can treat three-dimensional hydrodynamic calculations in a reactor pressure vessel, is well suited for evaluating the reactor transient performance with the SSR fuel bundles because it can calculate the water levels in the SSR at each channel grouping and therefore evaluate the core reactivity according to the water level changes in the SSR. 'Generator load rejection with total turbine bypass failure' and 'Recirculation flow control failure with increasing flow' were selected as cases which may increase the reactivity with the increasing water level in the SSR. It was found that the absolute value of the void reactivity coefficient in the SSR core was larger than that in the conventional water rod core because the core averaged void fraction in the SSR core, which has the vapor region above the water level in the SSR, was larger than that in the conventional water rod core. Therefore, AMCPR for the SSR core was a little larger than that for the conventional water rod core; however, the difference was smaller than 0.02 because the inlet of the SSR ascending path was designed to be small enough to prevent the rapid water level increase in the SSR. (authors)

[Study on quality evaluation of sequence and SSR information in transcriptome of Astragalus membranacus].

Science.gov (United States)

Chang, Yue; Yang, Song; Liu, Zhen-Peng; Ren, Wei-Chao; Liu, Jie; Ma, Wei

2016-04-01

In this study, 454/Roche GS FLX sequencing technology was used to obtain the data of the Astragalus membranaceus. Four hundred and fifty-four Sequencing System Software was applied to carry out the transcription of the group from scratch. Using MISA tools, 9 893 unigenes were selected for the sequence of the genome of A. membranaceus, and the information of SSR locus was analyzed. According to the result, the average length of reads was 413 bp, about 86% of the reads was involved in the splicing, the length of the N50 was 1 205 bp, the number of unigenes was measured by the whole transcript. 1 729 SSR loci in the A. membranaceus transcriptome were searched, the occurrence frequency of SSR was 9.24%, the frequency of SSR in the whole transcriptome was 13.42%, the average length of SSR was 7.97 kb. One hundred and twenty-seven kinds of core repeat sequences were found, the dominant type was TG/AC type of dinucleotide, it appeared to account for 4.25% of the total SSR locus. The results of the sequence of the transcription of the A. membranaceus transcriptome revealed the overall expression, and a large number of unigenessequence was obtained, and the SSR locus in the genome of the A. membranaceus is high, and the type is diverse, and the polymorphism of the gene is high. Copyright© by the Chinese Pharmaceutical Association.

A new set of validated SSR primers for application in mulberry ...

Indian Academy of Sciences (India)

user

2018-01-11

Jan 11, 2018 ... We chose 37 genomic sequences that had high number of di, tri and tetra SSR motifs from ... primers failed to produce any amplification products and ... Sericulture is a cottage industry that employs 8.03 million people across ... The resolving power of the SSR markers ranged from 0.11 (MulSatG100717) to.

Identification of molecular performance from oil palm clones based on SSR markers

Science.gov (United States)

Putri, Lollie Agustina P.; Basyuni, M.; Bayu, Eva S.; Arvita, D.; Arifiyanto, D.; Syahputra, I.

2018-03-01

In Indonesia, the oil palms are an important economic crop, producing food and raw materials for the food, confectionary, cosmetics and oleo-chemical industrial demands of oil palm products. Clonal oil palm offers the potential for greater productivity because it is possible to establish uniform tree stands comprising identical copies (clones) of a limited number of highly productive oil palms. Unfortunately, tissue culture sometimes accentuates the expression of detects in oil palm, particularly when embryogenesis is induced in particullar callus for prolonged periods. This research is conducted by taking individual tree sample of clone germplasm two years old. The purpose of this research is to molecular performance analysis of some oil palm clones based on SSR markers. A total of 30 trees oil palm clones were used for analysis. In this experiment, the DNA profile diversity was assessed using five loci of oil palm’s specific SSR markers. The results of the experiment indicated out of 3 SSR markers (FR-0779, FR-3663 and FR-0782) showed monomorphic of PCR product and 2 SSR markers (FR-0783 and FR- 3745) showed polymorphic of PCR product. There are 10 total number of PCR product. These preliminary results demonstrated SSR marker can be used to evaluate genetic relatedness among trees of oil palm clones.

Characterization of genic microsatellite markers derived from expressed sequence tags in Pacific abalone ( Haliotis discus hannai)

Science.gov (United States)

Li, Qi; Shu, Jing; Zhao, Cui; Liu, Shikai; Kong, Lingfeng; Zheng, Xiaodong

2010-01-01

Simple sequence repeat (SSR) markers were developed from the expressed sequence tags (ESTs) of Pacific abalone ( Haliotis discus hannai). Repeat motifs were found in 4.95% of the ESTs at a frequency of one repeat every 10.04 kb of EST sequences, after redundancy elimination. Seventeen polymorphic EST-SSRs were developed. The number of alleles per locus varied from 2-17, with an average of 6.8 alleles per locus. The expected and observed heterozygosities ranged from 0.159 to 0.928 and from 0.132 to 0.922, respectively. Twelve of the 17 loci (70.6%) were successfully amplified in H. diversicolor. Seventeen loci segregated in three families, with three showing the presence of null alleles (17.6%). The adequate level of variability and low frequency of null alleles observed in H. discus hannai, together with the high rate of transportability across Haliotis species, make this set of EST-SSR markers an important tool for comparative mapping, marker-assisted selection, and evolutionary studies, not only in the Pacific abalone, but also in related species.

Synthesis and carbon-11-labeling of p-MeO-SSR180575, a novel indoleacetamide-based candidate for PET imaging of the peripheral benzodiazepine receptor (TSPO 18 kDa)

International Nuclear Information System (INIS)

Damont, A.; Le Helleix, St.; Kuhnast, B.; Boisgard, R.; Tavitian, B.; Dolle, F.; Marguet, F.; Puech, F.

2011-01-01

Complete text of publication follows: Objectives: The 3-iso-quinolinecarboxamide [ 11 C]PK11195, despite its low brain uptake and high level of nonspecific binding, is still the most widely used PET-radioligand for the in vivo imaging of the peripheral benzodiazepine receptor (PBR or TSPO 18 kDa). Several new PBR radioligands are currently developed to replace [ 11 C]PK11195, e.g the pyrazolo[1, 5-a]pyrimidine-acetamides [ 11 C]DPA-713 and [ 18 F]DPA-714, the imidazo[1, 2-a]pyridine-acetamides [ 11 C]CLINME and [ 18 F]PBR111 and the N-benzyl-N-(2-phenoxy-aryl)- acetamides [ 11 C]PBR28 and [ 18 F]FEDAA1106. Another attractive newly identified chemical class of structures are the indole-acetamides and notably compounds derived from the lead compound SSR180575. Herein are reported the synthesis and the labelling with the positron-emitter carbon-11 (half-life: 20.38 min) of a novel derivative of SSR180575, bearing a para methoxy function on its phenyl ring. Methods: p-MeO-SSR180575 (1) was synthesized from commercially available 4-chloro-2-nitrotoluene in 10 steps. O-demethylation, performed with a boron tribromide solution in dichloromethane at low temperature, afforded the free phenol derivative 2. Carbon-11 labeling of p-MeO-SSR180575 (1) was performed using a TRACERLab FX-C Pro synthesizer (GEMS) and comprised (1) trapping of [ 11 C]MeOTf at -10 C in acetone (0.3 mL) containing the nor-derivative 2 (O-demethylated, 0.6-0.9 mg) and aq. 3N NaOH (8 μL); (2) heating at 110 C for 2 min; (3) concentration to dryness and taking up the residue in 1.0 mL of the HPLC mobile phase; (4) purification using semi-preparative reversed-phase HPLC (Waters Symmetry C-18 - eluent: CH 3 CN / H 2 O / TFA: 50 / 50 / 0.1 (v:v:v) - flow rate: 5 mL/min - detection at 254 nm) and (5) SepPak R Plus C-18-based formulation for i.v. injection. Results: p-MeO-SSR180575 (1) was obtained in 10% overall yield. The tricky and low-yielding step in our approach was the pyridazine ring formation

Genic and Intergenic SSR Database Generation, SNPs Determination and Pathway Annotations, in Date Palm (Phoenix dactylifera L.).

Science.gov (United States)

Mokhtar, Morad M; Adawy, Sami S; El-Assal, Salah El-Din S; Hussein, Ebtissam H A

2016-01-01

The present investigation was carried out aiming to use the bioinformatics tools in order to identify and characterize, simple sequence repeats within the third Version of the date palm genome and develop a new SSR primers database. In addition single nucleotide polymorphisms (SNPs) that are located within the SSR flanking regions were recognized. Moreover, the pathways for the sequences assigned by SSR primers, the biological functions and gene interaction were determined. A total of 172,075 SSR motifs was identified on date palm genome sequence with a frequency of 450.97 SSRs per Mb. Out of these, 130,014 SSRs (75.6%) were located within the intergenic regions with a frequency of 499 SSRs per Mb. While, only 42,061 SSRs (24.4%) were located within the genic regions with a frequency of 347.5 SSRs per Mb. A total of 111,403 of SSR primer pairs were designed, that represents 291.9 SSR primers per Mb. Out of the 111,403, only 31,380 SSR primers were in the genic regions, while 80,023 primers were in the intergenic regions. A number of 250,507 SNPs were recognized in 84,172 SSR flanking regions, which represents 75.55% of the total SSR flanking regions. Out of 12,274 genes only 463 genes comprising 896 SSR primers were mapped onto 111 pathways using KEGG data base. The most abundant enzymes were identified in the pathway related to the biosynthesis of antibiotics. We tested 1031 SSR primers using both publicly available date palm genome sequences as templates in the in silico PCR reactions. Concerning in vitro validation, 31 SSR primers among those used in the in silico PCR were synthesized and tested for their ability to detect polymorphism among six Egyptian date palm cultivars. All tested primers have successfully amplified products, but only 18 primers detected polymorphic amplicons among the studied date palm cultivars.

Development and identification of SSR markers associated with starch properties and β-carotene content in the storage root of sweet potato (Ipomoea batatas L.

Directory of Open Access Journals (Sweden)

Kai eZhang

2016-03-01

Full Text Available Sweet potato (Ipomoea batatas L. is a nutritious food crop and, based on the high starch content of its storage root, a potential bioethanol feedstock. Enhancing the nutritional value and starch quantity of storage roots are important goals of sweet potato breeding programs aimed at developing improved varieties for direct consumption, processing, and industrial uses. However, developing improved lines of sweet potato is challenging due to the genetic complexity of this plant and the lack of genome information. Short sequence repeat (SSR markers are powerful molecular tools for tracking important loci in crops and for molecular-based breeding strategies; however, few SSR markers and marker-trait associations have hitherto been identified in sweet potato. In this study, we identified 1,824 SSRs by using a de novo assembly of publicly available ESTs and mRNAs in sweet potato, and designed 1,476 primer pairs based on SSR-containing sequences. We mapped 214 pairs of primers in a natural population comprised of 239 germplasms, and identified 1,278 alleles with an average of 5.972 alleles per locus and a major allele frequency of 0.7702. Population structure analysis revealed two subpopulations in this panel of germplasms, and phenotypic characterization demonstrated that this panel is suitable for association mapping of starch-related traits. We identified 32, 16, and 17 SSR markers associated with starch content, β-carotene content, and starch composition in the storage root, respectively, using association analysis and further evaluation of a subset of sweet potato genotypes with various characteristics. The SSR markers identified here can be used to select varieties with desired traits and to investigate the genetic mechanism underlying starch and carotenoid formation in the starchy roots of sweet potato.

Development and Identification of SSR Markers Associated with Starch Properties and β-Carotene Content in the Storage Root of Sweet Potato (Ipomoea batatas L.).

Science.gov (United States)

Zhang, Kai; Wu, Zhengdan; Tang, Daobin; Lv, Changwen; Luo, Kai; Zhao, Yong; Liu, Xun; Huang, Yuanxin; Wang, Jichun

2016-01-01

Sweet potato (Ipomoea batatas L.) is a nutritious food crop and, based on the high starch content of its storage root, a potential bioethanol feedstock. Enhancing the nutritional value and starch quantity of storage roots are important goals of sweet potato breeding programs aimed at developing improved varieties for direct consumption, processing, and industrial uses. However, developing improved lines of sweet potato is challenging due to the genetic complexity of this plant and the lack of genome information. Short sequence repeat (SSR) markers are powerful molecular tools for tracking important loci in crops and for molecular-based breeding strategies; however, few SSR markers and marker-trait associations have hitherto been identified in sweet potato. In this study, we identified 1824 SSRs by using a de novo assembly of publicly available ESTs and mRNAs in sweet potato, and designed 1476 primer pairs based on SSR-containing sequences. We mapped 214 pairs of primers in a natural population comprised of 239 germplasms, and identified 1278 alleles with an average of 5.972 alleles per locus and a major allele frequency of 0.7702. Population structure analysis revealed two subpopulations in this panel of germplasms, and phenotypic characterization demonstrated that this panel is suitable for association mapping of starch-related traits. We identified 32, 16, and 17 SSR markers associated with starch content, β-carotene content, and starch composition in the storage root, respectively, using association analysis and further evaluation of a subset of sweet potato genotypes with various characteristics. The SSR markers identified here can be used to select varieties with desired traits and to investigate the genetic mechanism underlying starch and carotenoid formation in the starchy roots of sweet potato.

Genetic variation of maize (Zea mays L.) mutants based on ssr analysis

Energy Technology Data Exchange (ETDEWEB)

Hongni, Qin; Yilin, Cai; Chunrong, Yang; Guoqiang, Wang [Maize Research Institute of Southwest University, Chongqing (China)

2008-12-15

52 SSR primers that gave stable profiles amplified in sample of the Maize inbred line '082' and its 48 mutants were selected from 97 primers, and produced 170 polymorphic amplified fragments. The average number of allele per SSR locus was 3.27 with a range from 2 to 6. The polymorphism information content for the SSR loci varied from 0.039 to 0.715 with an average of 0.327. Genetic similarities among the 49 materials ranged from 0.377 to 1.000 with an average of 0.823. The 49 materials were divided into 6 groups by UPGMA. The results indicated that distinct variation existed among mutants. (authors)

Genetic variation of maize (Zea mays L.) mutants based on ssr analysis

International Nuclear Information System (INIS)

Qin Hongni; Cai Yilin; Yang Chunrong; Wang Guoqiang

2008-01-01

52 SSR primers that gave stable profiles amplified in sample of the Maize inbred line '082' and its 48 mutants were selected from 97 primers, and produced 170 polymorphic amplified fragments. The average number of allele per SSR locus was 3.27 with a range from 2 to 6. The polymorphism information content for the SSR loci varied from 0.039 to 0.715 with an average of 0.327. Genetic similarities among the 49 materials ranged from 0.377 to 1.000 with an average of 0.823. The 49 materials were divided into 6 groups by UPGMA. The results indicated that distinct variation existed among mutants. (authors)

Diversity analysis in Cannabis sativa based on large-scale development of expressed sequence tag-derived simple sequence repeat markers.

Science.gov (United States)

Gao, Chunsheng; Xin, Pengfei; Cheng, Chaohua; Tang, Qing; Chen, Ping; Wang, Changbiao; Zang, Gonggu; Zhao, Lining

2014-01-01

Cannabis sativa L. is an important economic plant for the production of food, fiber, oils, and intoxicants. However, lack of sufficient simple sequence repeat (SSR) markers has limited the development of cannabis genetic research. Here, large-scale development of expressed sequence tag simple sequence repeat (EST-SSR) markers was performed to obtain more informative genetic markers, and to assess genetic diversity in cannabis (Cannabis sativa L.). Based on the cannabis transcriptome, 4,577 SSRs were identified from 3,624 ESTs. From there, a total of 3,442 complementary primer pairs were designed as SSR markers. Among these markers, trinucleotide repeat motifs (50.99%) were the most abundant, followed by hexanucleotide (25.13%), dinucleotide (16.34%), tetranucloetide (3.8%), and pentanucleotide (3.74%) repeat motifs, respectively. The AAG/CTT trinucleotide repeat (17.96%) was the most abundant motif detected in the SSRs. One hundred and seventeen EST-SSR markers were randomly selected to evaluate primer quality in 24 cannabis varieties. Among these 117 markers, 108 (92.31%) were successfully amplified and 87 (74.36%) were polymorphic. Forty-five polymorphic primer pairs were selected to evaluate genetic diversity and relatedness among the 115 cannabis genotypes. The results showed that 115 varieties could be divided into 4 groups primarily based on geography: Northern China, Europe, Central China, and Southern China. Moreover, the coefficient of similarity when comparing cannabis from Northern China with the European group cannabis was higher than that when comparing with cannabis from the other two groups, owing to a similar climate. This study outlines the first large-scale development of SSR markers for cannabis. These data may serve as a foundation for the development of genetic linkage, quantitative trait loci mapping, and marker-assisted breeding of cannabis.

Synthesis and carbon-11-labeling of p-MeO-SSR180575, a novel indoleacetamide-based candidate for PET imaging of the peripheral benzodiazepine receptor (TSPO 18 kDa)

International Nuclear Information System (INIS)

Damont, A.L.; Le Helleix, St.; Kuhnast, B.; Boisgard, R.; Tavitian, B.; Dolle, F.; Marguet, F.; Puech, F.

2011-01-01

Complete text of publication follows: Objectives: The 3-iso-quinolinecarboxamide [ 11 C]PK11195, despite its low brain uptake and high level of nonspecific binding, is still the most widely used PET-radioligand for the in vivo imaging of the peripheral benzodiazepine receptor (PBR or TSPO 18 kDa). Several new PBR radioligands are currently developed to replace [ 11 C]PK11195 [1], e.g the pyrazolo[1, 5-a]pyrimidine-acetamides [ 11 C]DPA-713 and [ 18 F]DPA-714, the imidazo[1, 2-a]pyridine-acetamides [ 11 C]CLINME and [ 18 F]PBR111 and the N-benzyl-N-(2-phenoxy-aryl)- acetamides [ 11 C]PBR28 and [ 18 F]FEDAA1106. Another attractive newly identified chemical class of structures are the indole-acetamides and notably compounds derived from the lead compound SSR180575 [2]. Herein are reported the synthesis and the labelling with the positron-emitter carbon-11 (half-life: 20.38 min) of a novel derivative of SSR180575, bearing a para methoxy function on its phenyl ring. Methods: p-MeO-SSR180575 (1) was synthesized from commercially available 4-chloro-2-nitrotoluene in 10 steps. O-demethylation, performed with a boron tribromide solution in dichloromethane at low temperature, afforded the free phenol derivative 2. Carbon-11 labeling of p-MeO-SSR180575 (1) was performed using a TRACERLab FX-C Pro synthesizer (GEMS) and comprised (1) trapping of [ 11 C]MeOTf at -10 C in acetone (0.3 mL) containing the nor-derivative 2 (O-demethylated, 0.6-0.9 mg) and aq. 3N NaOH (8 μL); (2) heating at 110 C for 2 min; (3) concentration to dryness and taking up the residue in 1.0 mL of the HPLC mobile phase; (4) purification using semi-preparative reversed-phase HPLC (Waters Symmetry R C-18 - eluent: CH 3 CN / H 2 O / TFA: 50 / 50 / 0.1 (v:v:v) - flow rate: 5 mL/min - detection at 254 nm) and (5) SepPak Plus R C-18-based formulation for i.v. injection approach was the pyridazine ring formation reaction that proceeded partially: the maximum conversion of the intermediate diester-indole reacting

Genetic Diversity in Various Accessions of Pineapple [Ananas comosus (L.) Merr.] Using ISSR and SSR Markers.

Science.gov (United States)

Wang, Jian-Sheng; He, Jun-Hu; Chen, Hua-Rui; Chen, Ye-Yuan; Qiao, Fei

2017-12-01

Inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers were used to assess the genetic diversity of 36 pineapple accessions that were introduced from 10 countries/regions. Thirteen ISSR primers amplified 96 bands, of which 91 (93.65%) were polymorphic, whereas 20 SSR primers amplified 73 bands, of which 70 (96.50%) were polymorphic. Nei's gene diversity (h = 0.28), Shannon's information index (I = 0.43), and polymorphism information content (PIC = 0.29) generated using the SSR primers were higher than that with ISSR primers (h =  0.23, I = 0.37, PIC = 0.24), thereby suggesting that the SSR system is more efficient than the ISSR system in assessing genetic diversity in various pineapple accessions. Mean genetic similarities were 0.74, 0.61, and 0.69, as determined using ISSR, SSR, and combined ISSR/SSR, respectively. These results suggest that the genetic diversity among pineapple accessions is very high. We clustered the 36 pineapple accessions into three or five groups on the basis of the phylogenetic trees constructed based on the results of ISSR, SSR, and combined ISSR/SSR analyses using the unweighted pair-group with arithmetic averaging (UPGMA) method. The results of principal components analysis (PCA) also supported the UPGMA clustering. These results will be useful not only for the scientific conservation and management of pineapple germplasm but also for the improvement of the current pineapple breeding strategies.

WGSSAT: A High-Throughput Computational Pipeline for Mining and Annotation of SSR Markers From Whole Genomes.

Science.gov (United States)

Pandey, Manmohan; Kumar, Ravindra; Srivastava, Prachi; Agarwal, Suyash; Srivastava, Shreya; Nagpure, Naresh S; Jena, Joy K; Kushwaha, Basdeo

2018-03-16

Mining and characterization of Simple Sequence Repeat (SSR) markers from whole genomes provide valuable information about biological significance of SSR distribution and also facilitate development of markers for genetic analysis. Whole genome sequencing (WGS)-SSR Annotation Tool (WGSSAT) is a graphical user interface pipeline developed using Java Netbeans and Perl scripts which facilitates in simplifying the process of SSR mining and characterization. WGSSAT takes input in FASTA format and automates the prediction of genes, noncoding RNA (ncRNA), core genes, repeats and SSRs from whole genomes followed by mapping of the predicted SSRs onto a genome (classified according to genes, ncRNA, repeats, exonic, intronic, and core gene region) along with primer identification and mining of cross-species markers. The program also generates a detailed statistical report along with visualization of mapped SSRs, genes, core genes, and RNAs. The features of WGSSAT were demonstrated using Takifugu rubripes data. This yielded a total of 139 057 SSR, out of which 113 703 SSR primer pairs were uniquely amplified in silico onto a T. rubripes (fugu) genome. Out of 113 703 mined SSRs, 81 463 were from coding region (including 4286 exonic and 77 177 intronic), 7 from RNA, 267 from core genes of fugu, whereas 105 641 SSR and 601 SSR primer pairs were uniquely mapped onto the medaka genome. WGSSAT is tested under Ubuntu Linux. The source code, documentation, user manual, example dataset and scripts are available online at https://sourceforge.net/projects/wgssat-nbfgr.

Simple sequence repeat marker loci discovery using SSR primer.

Science.gov (United States)

Robinson, Andrew J; Love, Christopher G; Batley, Jacqueline; Barker, Gary; Edwards, David

2004-06-12

Simple sequence repeats (SSRs) have become important molecular markers for a broad range of applications, such as genome mapping and characterization, phenotype mapping, marker assisted selection of crop plants and a range of molecular ecology and diversity studies. With the increase in the availability of DNA sequence information, an automated process to identify and design PCR primers for amplification of SSR loci would be a useful tool in plant breeding programs. We report an application that integrates SPUTNIK, an SSR repeat finder, with Primer3, a PCR primer design program, into one pipeline tool, SSR Primer. On submission of multiple FASTA formatted sequences, the script screens each sequence for SSRs using SPUTNIK. The results are parsed to Primer3 for locus-specific primer design. The script makes use of a Web-based interface, enabling remote use. This program has been written in PERL and is freely available for non-commercial users by request from the authors. The Web-based version may be accessed at http://hornbill.cspp.latrobe.edu.au/

Development and characterization of polymorphic genomic-SSR markers in Asian long-horned beetle (Anoplophora glabripennis).

Science.gov (United States)

Liu, Zhaoyang; Tao, Jing; Luo, Youqing

2017-12-01

The Asian long-horned beetle (ALB), Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae: Lamiinae), is a wood-borer and polyphagous xylophage that is native to Asia. It infests and seriously harms healthy trees, and therefore is a cause for considerable environmental concern. The analysis of population genetic structure of ALB and sibling species Anoplophora nobilis (Ganglbauer) will not only help to clarify the relationship between environmental variables and mechanisms of speciation, but also will enhance our understanding of evolutionary processes. However, the known genetic markers, particularly microsatellites, are limited for this species. SSRLocator software was used to analyze the distribution and frequencies of genomic simple sequence repeat (SSR), to infer the basic characteristics of repeat motifs, and to design primers. We developed SSR loci of 2-6 repeated units, including 10,650 perfect SSRs, and found 140 types of repeat motifs. A total of 2621 SSR markers were discovered in ALB whole-genome shotgun sequences. 48 pairs of SSR primers were randomly chosen from 2621 SSR markers, and half of these 48 pairs were polymorphic containing 4 di-, 7 tri-, 2 tetra-, and 11-hexamer SSRs. Four populations test the effectiveness of the primers. These results suggest that our method for whole-genome SSR screening is feasible and efficient, and the SSR markers developed in this study are suitable for further population genetics studies of ALB. Moreover, they may also be useful for the development of SSRs for other Coleoptera.

High-throughput development of genome-wide locus-specific informative SSR markers in wheat

Science.gov (United States)

Although simple sequence repeat (SSR) markers are not new, they are still useful and often used markers in molecular mapping and marker-assisted breeding, particularly in developing countries. However, locus-specific SSR markers could be more useful and informative in wheat breeding and genetic stud...

Development and genetic mapping of SSR markers in foxtail millet [Setaria italica (L.) P. Beauv.].

Science.gov (United States)

Jia, Xiaoping; Zhang, Zhongbao; Liu, Yinghui; Zhang, Chengwei; Shi, Yunsu; Song, Yanchun; Wang, Tianyu; Li, Yu

2009-02-01

SSR markers are desirable markers in analysis of genetic diversity, quantitative trait loci mapping and gene locating. In this study, SSR markers were developed from two genomic libraries enriched for (GA)n and (CA)n of foxtail millet [Setaria italica (L.) P. Beauv.], a crop of historical importance in China. A total of 100 SSR markers among the 193 primer pairs detected polymorphism between two mapping parents of an F(2) population, i.e. "B100" of cultivated S. italica and "A10" of wild S. viridis. Excluding 14 markers with unclear amplifications, and five markers unlinked with any linkage group, a foxtail millet SSR linkage map was constructed by integrating 81 new developed SSR markers with 20 RFLP anchored markers. The 81 SSRs covered nine chromosomes of foxtail millet. The length of the map was 1,654 cM, with an average interval distance between markers of 16.4 cM. The 81 SSR markers were not evenly distributed throughout the nine chromosomes, with Ch.8 harbouring the least (3 markers) and Ch.9 harbouring the most (18 markers). To verify the usefulness of the SSR markers developed, 37 SSR markers were randomly chosen to analyze genetic diversity of 40 foxtail millet accessions. Totally 228 alleles were detected, with an average 6.16 alleles per locus. Polymorphism information content (PIC) value for each locus ranged from 0.413 to 0.847, with an average of 0.697. A positive correlation between PIC and number of alleles and between PIC and number of repeat unit were found [0.802 and 0.429, respectively (P < 0.01)]. UPGMA analysis revealed that the 40 foxtail millet cultivars could be grouped into five clusters in which the landraces' grouping was largely consistent with ecotypes while the breeding varieties from different provinces in China tended to be grouped together.

Development and validation of genic-SSR markers in sesame by RNA-seq.

Science.gov (United States)

Zhang, Haiyang; Wei, Libin; Miao, Hongmei; Zhang, Tide; Wang, Cuiying

2012-07-16

Sesame (Sesamum indicum L.) is one of the most important oil crops; however, a lack of useful molecular markers hinders current genetic research. We performed transcriptome sequencing of samples from different sesame growth and developmental stages, and mining of genic-SSR markers to identify valuable markers for sesame molecular genetics research. In this study, 75 bp and 100 bp paired-end RNA-seq was used to sequence 24 cDNA libraries, and 42,566 uni-transcripts were assembled from more than 260 million filtered reads. The total length of uni-transcript sequences was 47.99 Mb, and 7,324 SSRs (SSRs ≥15 bp) and 4,440 SSRs (SSRs ≥18 bp) were identified. On average, there was one genic-SSR per 6.55 kb (SSRs ≥15 bp) or 10.81 kb (SSRs ≥18 bp). Among perfect SSRs (≥18 bp), di-nucleotide motifs (48.01%) were the most abundant, followed by tri- (20.96%), hexa- (25.37%), penta- (2.97%), tetra- (2.12%), and mono-nucleotides (0.57%). The top four motif repeats were (AG/CT)n [1,268 (34.51%)], (CA/TG)n [281 (7.65%)], (AT/AT)n [215 (5.85%)], and (GAA/TTC)n [131 (3.57%)]. A total of 2,164 SSR primer pairs were identified in the 4,440 SSR-containing sequences (≥18 bp), and 300 SSR primer pairs were randomly chosen for validation. These SSR markers were amplified and validated in 25 sesame accessions (24 cultivated accessions, one wild species). 276 (92.0%) primer pairs yielded PCR amplification products in 24 cultivars. Thirty two primer pairs (11.59%) exhibited polymorphisms. Moreover, 203 primer pairs (67.67%) yielded PCR amplicons in the wild accession and 167 (60.51%) were polymorphic between species. A UPGMA dendrogram based on genetic similarity coefficients showed that the correlation between genotype and geographical source was low and that the genetic basis of sesame in China is narrow, as previously reported. The 32 polymorphic primer pairs were validated using an F2 mapping population; 18 primer pairs exhibited polymorphisms between the parents, and 14

A simple ssr analysis for genetic diversity estimation of maize landraces

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Ignjatovic-Micic Dragana

2015-01-01

Full Text Available collection of 2217 landraces from western Balkan (former Yugoslavia is maintained at Maize Research Institute Zemun Polje gene bank. Nine flint and nine dent accessions from six agro-ecological groups (races, chosen on the basis of diverse pedigrees, were analyzed for genetic relatedness using phenotypic and simple sequence repeat (SSR markers. One of the aims was to establish a reliable set of SSR markers for a rapid diversity analysis using polyacrilamide gels and ethidium bromide staining. In the principal component analysis (PCA the first three principal components accounted for 80.86% of total variation and separated most of the flint from dent landraces. Ten SSR primers revealed a total of 56 and 63 alleles in flint and dent landraces, respectively, with low stuttering and good allele resolution on the gels. High average PIC value (0.822 also supports informativeness and utility of the markers used in this study. Higher genetic variation was observed among flint genotypes, as genetic distances between flint landraces covered a larger range of values (0.11- 0.38 than between dent (0.22 - 0.33 genotypes. Both phenotypic and SSR analyses distinguished flint and dent landraces, but neither of them could abstract agro-ecological groups. The SSR method used gave clear, easy to read band patterns that could be used for reliable allele frequency determination. Genetic diversity revealed for both markers indicated that the landraces were highly adapted to specific environmental conditions and purposes and could be valuable sources of genetic variability. [Projekat Ministarstva nauke Republike Srbije, br. TR31028: Exploitation of maize diversity to improve grain quality and drought tolerance

Use of SSR markers for DNA fingerprinting and diversity analysis of Pakistani sugarcane (Saccharum spp. hybrids) cultivars

Science.gov (United States)

In recent years SSR markers have been used widely for genetic analysis. The objective of this study was to use an SSR-based marker system to develop the molecular fingerprints and analyze the genetic relationship of sugarcane cultivars grown in Pakistan. Twenty-one highly polymorphic SSR markers wer...

Transcriptomic analysis, genic SSR development, and genetic diversity of proso millet (Panicum miliaceum; Poaceae).

Science.gov (United States)

Hou, Siyu; Sun, Zhaoxia; Li, Yaoshen; Wang, Yijie; Ling, Hubin; Xing, Guofang; Han, Yuanhuai; Li, Hongying

2017-07-01

Proso millet ( Panicum miliaceum ; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future.

Development and Characterization of Simple Sequence Repeat (SSR) Markers Based on RNA-Sequencing of Medicago sativa and In silico Mapping onto the M. truncatula Genome

Science.gov (United States)

Wang, Zan; Yu, Guohui; Shi, Binbin; Wang, Xuemin; Qiang, Haiping; Gao, Hongwen

2014-01-01

Sufficient codominant genetic markers are needed for various genetic investigations in alfalfa since the species is an outcrossing autotetraploid. With the newly developed next generation sequencing technology, a large amount of transcribed sequences of alfalfa have been generated and are available for identifying SSR markers by data mining. A total of 54,278 alfalfa non-redundant unigenes were assembled through the Illumina HiSeqTM 2000 sequencing technology. Based on 3,903 unigene sequences, 4,493 SSRs were identified. Tri-nucleotide repeats (56.71%) were the most abundant motif class while AG/CT (21.7%), AGG/CCT (19.8%), AAC/GTT (10.3%), ATC/ATG (8.8%), and ACC/GGT (6.3%) were the subsequent top five nucleotide repeat motifs. Eight hundred and thirty- seven EST-SSR primer pairs were successfully designed. Of these, 527 (63%) primer pairs yielded clear and scored PCR products and 372 (70.6%) exhibited polymorphisms. High transferability was observed for ssp falcata at 99.2% (523) and 71.7% (378) in M. truncatula. In addition, 313 of 527 SSR marker sequences were in silico mapped onto the eight M. truncatula chromosomes. Thirty-six polymorphic SSR primer pairs were used in the genetic relatedness analysis of 30 Chinese alfalfa cultivated accessions generating a total of 199 scored alleles. The mean observed heterozygosity and polymorphic information content were 0.767 and 0.635, respectively. The codominant markers not only enriched the current resources of molecular markers in alfalfa, but also would facilitate targeted investigations in marker-trait association, QTL mapping, and genetic diversity analysis in alfalfa. PMID:24642969

Identification and characterization of gene-based SSR markers in date palm (Phoenix dactylifera L.

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Zhao Yongli

2012-12-01

Full Text Available Abstract Background Date palm (Phoenix dactylifera L. is an important tree in the Middle East and North Africa due to the nutritional value of its fruit. Molecular Breeding would accelerate genetic improvement of fruit tree through marker assisted selection. However, the lack of molecular markers in date palm restricts the application of molecular breeding. Results In this study, we analyzed 28,889 EST sequences from the date palm genome database to identify simple-sequence repeats (SSRs and to develop gene-based markers, i.e. expressed sequence tag-SSRs (EST-SSRs. We identified 4,609 ESTs as containing SSRs, among which, trinucleotide motifs (69.7% were the most common, followed by tetranucleotide (10.4% and dinucleotide motifs (9.6%. The motif AG (85.7% was most abundant in dinucleotides, while motifs AGG (26.8%, AAG (19.3%, and AGC (16.1% were most common among trinucleotides. A total of 4,967 primer pairs were designed for EST-SSR markers from the computational data. In a follow up laboratory study, we tested a sample of 20 random selected primer pairs for amplification and polymorphism detection using genomic DNA from date palm cultivars. Nearly one-third of these primer pairs detected DNA polymorphism to differentiate the twelve date palm cultivars used. Functional categorization of EST sequences containing SSRs revealed that 3,108 (67.4% of such ESTs had homology with known proteins. Conclusion Date palm EST sequences exhibits a good resource for developing gene-based markers. These genic markers identified in our study may provide a valuable genetic and genomic tool for further genetic research and varietal development in date palm, such as diversity study, QTL mapping, and molecular breeding.

Genetic diversity and DNA fingerprinting in jute (Corchorus spp. based on SSR markers

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Liwu Zhang

2015-10-01

Full Text Available Genetic diversity analysis and DNA finger printing are very useful in breeding programs, seed conservation and management. Jute (Corchorus spp. is the second most important natural fiber crop after cotton. DNA fingerprinting studies in jute using SSR markers are limited. In this study, 58 jute accessions, including two control varieties (Huangma 179 and Kuanyechangguo from the official variety registry in China were evaluated with 28 pairs of SSR primers. A total of 184 polymorphic loci were identified. Each primer detected 3 to 15 polymorphic loci, with an average of 6.6. The 58 jute accessions were DNA-fingerprinted with 67 SSR markers from the 28 primer pairs. These markers differentiated the 58 jute accessions from one another, with CoSSR305-120 and CoSSR174-195 differentiating Huangma 179 and Kuanyechangguo, respectively. NTSYS-pc2.10 software was used to analyze the genetic diversity in the 58 jute accessions. Their genetic similarity coefficients ranged from 0.520 to 0.910 with an average of 0.749, indicating relatively great genetic diversity among them. The 58 jute accessions were divided into four groups with the coefficient 0.710 used as a value for classification, consistent with their species and pedigrees. All these results may be useful both for protection of intellectual property rights of jute accessions and for jute improvement.

Genetic diversity and DNA fingerprinting in jute(Corchorus spp.) based on SSR markers

Institute of Scientific and Technical Information of China (English)

Liwu; Zhang; Rongrong; Cai; Minhang; Yuan; Aifen; Tao; Jiantang; Xu; Lihui; Lin; Pingping; Fang; Jianmin; Qi

2015-01-01

Genetic diversity analysis and DNA finger printing are very useful in breeding programs,seed conservation and management. Jute(Corchorus spp.) is the second most important natural fiber crop after cotton. DNA fingerprinting studies in jute using SSR markers are limited. In this study, 58 jute accessions, including two control varieties(Huangma 179 and Kuanyechangguo) from the official variety registry in China were evaluated with 28 pairs of SSR primers. A total of 184 polymorphic loci were identified. Each primer detected 3 to 15 polymorphic loci, with an average of 6.6. The 58 jute accessions were DNA-fingerprinted with 67 SSR markers from the 28 primer pairs. These markers differentiated the 58 jute accessions from one another, with Co SSR305-120 and Co SSR174-195 differentiating Huangma 179 and Kuanyechangguo, respectively. NTSYS-pc2.10 software was used to analyze the genetic diversity in the 58 jute accessions. Their genetic similarity coefficients ranged from 0.520 to 0.910 with an average of 0.749, indicating relatively great genetic diversity among them. The 58 jute accessions were divided into four groups with the coefficient 0.710 used as a value for classification, consistent with their species and pedigrees. All these results may be useful both for protection of intellectual property rights of jute accessions and for jute improvement.

Novel and highly informative Capsicum SSR markers and their cross-species transferability.

Science.gov (United States)

Buso, G S C; Reis, A M M; Amaral, Z P S; Ferreira, M E

2016-09-23

This study was undertaken primarily to develop new simple sequence repeat (SSR) markers for Capsicum. As part of this project aimed at broadening the use of molecular tools in Capsicum breeding, two genomic libraries enriched for AG/TC repeat sequences were constructed for Capsicum annuum. A total of 475 DNA clones were sequenced from both libraries and 144 SSR markers were tested on cultivated and wild species of Capsicum. Forty-five SSR markers were randomly selected to genotype a panel of 48 accessions of the Capsicum germplasm bank. The number of alleles per locus ranged from 2 to 11, with an average of 6 alleles. The polymorphism information content was on average 0.60, ranging from 0.20 to 0.83. The cross-species transferability to seven cultivated and wild Capsicum species was tested with a set of 91 SSR markers. We found that a high proportion of the loci produced amplicons in all species tested. C. frutescens had the highest number of transferable markers, whereas the wild species had the lowest. Our results indicate that the new markers can be readily used in genetic analyses of Capsicum.

Assessment of inter- and intra-cultivar variations in olive using SSR markers

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Ahmet Ipek

2012-10-01

Full Text Available Olive (Olea europaea L. production in the world has been made by using many cultivars, and the genetic uniformity of commercial cultivars is important for standard olive oil and table olive production. The genetic variation among and within commonly cultivated olive cultivars in Turkey was analyzed using SSR markers. A total of 135 leaf samples were collected from 11 commonly cultivated olive cultivars from 11 provinces in four geographical regions of Turkey. Seven SSR primer pairs generated 46 SSR markers, and the number of SSR markers per primer pair ranged from 4 (UDO-14 to 9 (GAPU-89 with an average of 6.57. This high level of SSR polymorphism suggests that olive production in Turkey has been made using genetically diverse olive cultivars and this high level of genetic variation is probably due to the location of Turkey in the center of the origin of olive. The UPGMA dendrogram, developed to visualize the estimated genetic relationships among the 135 samples, demonstrated that the clustering of olive cultivars was not based on geographical regions of cultivation. Presence of genetic variation was detected within a nationwide grown Turkish olive cultivar, called 'Gemlik'. Olive growers successfully discriminated olive cultivars with distinct morphological and pomological characters. However, there was some confusion about the identification of cultivars with similar phenotypic traits. To prevent misidentification of olive cultivars and to minimize intra-cultivar variation, certified propagation materials which were characterized using DNA based molecular markers should be used during the establishment of new olive orchards.

GMATA: An Integrated Software Package for Genome-Scale SSR Mining, Marker Development and Viewing.

Science.gov (United States)

Wang, Xuewen; Wang, Le

2016-01-01

Simple sequence repeats (SSRs), also referred to as microsatellites, are highly variable tandem DNAs that are widely used as genetic markers. The increasing availability of whole-genome and transcript sequences provides information resources for SSR marker development. However, efficient software is required to efficiently identify and display SSR information along with other gene features at a genome scale. We developed novel software package Genome-wide Microsatellite Analyzing Tool Package (GMATA) integrating SSR mining, statistical analysis and plotting, marker design, polymorphism screening and marker transferability, and enabled simultaneously display SSR markers with other genome features. GMATA applies novel strategies for SSR analysis and primer design in large genomes, which allows GMATA to perform faster calculation and provides more accurate results than existing tools. Our package is also capable of processing DNA sequences of any size on a standard computer. GMATA is user friendly, only requires mouse clicks or types inputs on the command line, and is executable in multiple computing platforms. We demonstrated the application of GMATA in plants genomes and reveal a novel distribution pattern of SSRs in 15 grass genomes. The most abundant motifs are dimer GA/TC, the A/T monomer and the GCG/CGC trimer, rather than the rich G/C content in DNA sequence. We also revealed that SSR count is a linear to the chromosome length in fully assembled grass genomes. GMATA represents a powerful application tool that facilitates genomic sequence analyses. GAMTA is freely available at http://sourceforge.net/projects/gmata/?source=navbar.

Genetic Diversity and Identification of Chinese-Grown Pecan Using ISSR and SSR Markers

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Zhong-Ren Guo

2011-12-01

Full Text Available Pecan is an important horticultural nut crop originally from North America and now widely cultivated in China for its high ecological, ornamental and economic value. Currently, there are over one hundred cultivars grown in China, including introduced American cultivars and Chinese seedling breeding cultivars. Molecular markers were used to assess the genetic diversity of these cultivars and to identify the pedigrees of fine pecan plants with good characteristics and no cultivar-related data. A total of 77 samples grown in China were studied, including 14 introduced cultivars, 12 domestic seedling breeding cultivars, and 49 fine pecan plants with no cultivar data, together with Carya cathayensis and Juglans nigra. A total of 77 ISSR and 19 SSR primers were prescreened; 10 ISSR and eight SSR primers were selected, yielding a total of 94 amplified bands (100% polymorphic in the range of 140–1,950 bp for the ISSR and 70 amplified bands (100% polymorphic in the range of 50–350 bp for SSR markers. Genetic diversity analyses indicated Chinese-grown pecan cultivars and fine plants had significant diversity at the DNA level. The dengrograms constructed with ISSR, SSR or combined data were very similar, but showed very weak grouping association with morphological characters. However, the progeny were always grouped with the parents. The great diversity found among the Chinese cultivars and the interesting germplasm of the fine pecan plants analyzed in this study are very useful for increasing the diversity of the pecan gene pool. All 77 accessions in this study could be separated based on the ISSR and SSR fingerprints produced by one or more primers. The results of our study also showed that ISSR and SSR techniques were both suitable for genetic diversity analyses and the identification of pecan resources.

Genetic diversity and identification of Chinese-grown pecan using ISSR and SSR markers.

Science.gov (United States)

Jia, Xiao-Dong; Wang, Tao; Zhai, Min; Li, Yong-Rong; Guo, Zhong-Ren

2011-12-06

Pecan is an important horticultural nut crop originally from North America and now widely cultivated in China for its high ecological, ornamental and economic value. Currently, there are over one hundred cultivars grown in China, including introduced American cultivars and Chinese seedling breeding cultivars. Molecular markers were used to assess the genetic diversity of these cultivars and to identify the pedigrees of fine pecan plants with good characteristics and no cultivar-related data. A total of 77 samples grown in China were studied, including 14 introduced cultivars, 12 domestic seedling breeding cultivars, and 49 fine pecan plants with no cultivar data, together with Carya cathayensis and Juglans nigra. A total of 77 ISSR and 19 SSR primers were prescreened; 10 ISSR and eight SSR primers were selected, yielding a total of 94 amplified bands (100% polymorphic) in the range of 140-1,950 bp for the ISSR and 70 amplified bands (100% polymorphic) in the range of 50-350 bp for SSR markers. Genetic diversity analyses indicated Chinese-grown pecan cultivars and fine plants had significant diversity at the DNA level. The dengrograms constructed with ISSR, SSR or combined data were very similar, but showed very weak grouping association with morphological characters. However, the progeny were always grouped with the parents. The great diversity found among the Chinese cultivars and the interesting germplasm of the fine pecan plants analyzed in this study are very useful for increasing the diversity of the pecan gene pool. All 77 accessions in this study could be separated based on the ISSR and SSR fingerprints produced by one or more primers. The results of our study also showed that ISSR and SSR techniques were both suitable for genetic diversity analyses and the identification of pecan resources.

Development and validation of new SSR markers from expressed regions in the garlic genome

Science.gov (United States)

Limited number of simple sequence repeat (SSR) markers is available for the genome of garlic (Allium sativum L.) although SSR markers have become one of the most preferred marker systems because they are typically co-dominant, reproducible, cross species transferable and highly polymorphic. In this ...

Analysis of the genetic diversity of super sweet corn inbred lines using SSR and SSAP markers.

Science.gov (United States)

Ko, W R; Sa, K J; Roy, N S; Choi, H-J; Lee, J K

2016-01-22

In this study, we compared the efficiency of simple sequence repeat (SSR) and sequence specific amplified polymorphism (SSAP) markers for analyzing genetic diversity, genetic relationships, and population structure of 87 super sweet corn inbred lines from different origins. SSR markers showed higher average gene diversity and Shannon's information index than SSAP markers. To assess genetic relationships and characterize inbred lines using SSR and SSAP markers, genetic similarity (GS) matrices were constructed. The dendrogram using SSR marker data showed a complex pattern with nine clusters and a GS of 53.0%. For SSAP markers, three clusters were observed with a GS of 50.8%. Results of combined marker data showed six clusters with 53.5% GS. To analyze the genetic population structure of SSR and SSAP marker data, the 87 inbred lines were divided into groups I, II, and admixed based on the membership probability threshold of 0.8. Using combined marker data, the population structure was K = 3 and was divided into groups I, II, III, and admixed. This study represents a comparative analysis of SSR and SSAP marker data for the study of genetic diversity and genetic relationships in super sweet corn inbred lines. Our results would be useful for maize-breeding programs in Korea.

Development and Molecular Characterization of Novel Polymorphic Genomic DNA SSR Markers in Lentinula edodes.

Science.gov (United States)

Moon, Suyun; Lee, Hwa-Yong; Shim, Donghwan; Kim, Myungkil; Ka, Kang-Hyeon; Ryoo, Rhim; Ko, Han-Gyu; Koo, Chang-Duck; Chung, Jong-Wook; Ryu, Hojin

2017-06-01

Sixteen genomic DNA simple sequence repeat (SSR) markers of Lentinula edodes were developed from 205 SSR motifs present in 46.1-Mb long L. edodes genome sequences. The number of alleles ranged from 3-14 and the major allele frequency was distributed from 0.17-0.96. The values of observed and expected heterozygosity ranged from 0.00-0.76 and 0.07-0.90, respectively. The polymorphic information content value ranged from 0.07-0.89. A dendrogram, based on 16 SSR markers clustered by the paired hierarchical clustering' method, showed that 33 shiitake cultivars could be divided into three major groups and successfully identified. These SSR markers will contribute to the efficient breeding of this species by providing diversity in shiitake varieties. Furthermore, the genomic information covered by the markers can provide a valuable resource for genetic linkage map construction, molecular mapping, and marker-assisted selection in the shiitake mushroom.

SSR markers reveal genetic variation between improved cassava ...

African Journals Online (AJOL)

SERVER

2007-12-03

Dec 3, 2007 ... Numerical Taxonomy and Multivariate Analysis System software .... DNA extraction and polymerase chain reaction with SSR .... Primers that have PIC value falling between 0.50 to 0.70 ..... Woodman, Lee M, Porter K (2000).

APPLICATION OF RYE SSR MARKERS FOR DETECTION OF GENETIC DIVERSITY IN TRITICALE

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Želmíra Balážová

2016-06-01

Full Text Available Present study aims to testify usefulness of particular rye SSR markers for the detection of genetic diversity degree in the set of 20 triticale cultivars coming from different European countries. For this purpose, a set of six rye SSR markers were used. The set of six polymorphic markers provided 22 alleles with an average frequency of 3.67 alleles per locus. The number of alleles ranged between 2 (SCM43 and 5 (SCM28, SCM86. Resulting from the number and frequency of alleles diversity index (DI, polymorphic information content (PIC and probability of identity (PI were calculated. An average value of PIC for 6 SSR markers was 0.505, the highest value was calculated for rye SSR marker SCM86 (0.706. Based on UPGMA algorithm, a dendrogram was constructed. In dendrogram cultivars were divided into two main clusters. The first cluster contained two cultivars, Russian cultivar Greneder and Slovak cultivar Largus, and second included 18 cultivars. Genetically the closest were two Greek cultivars (Niobi and Thisbi and were close to other Greek cultivar Vrodi. It was possible to separate triticale cultivars of spring and winter form in dendrogram. Results showed the utility of rye microsatellite markers for estimation of genetic diversity of European triticale genotypes leading to genotype identification.

Impedance characteristics of DFIGs considering the impacts of DFIG numbers and its application on SSR analysis

Science.gov (United States)

You, J. J.; Ning, W. Y.; Jiang, H.; Dong, Y. X.; Liu, H.; Li, Y.

2017-05-01

Sub-synchronous resonance (SSR) occurred in the power system with both Doubly Fed Induction Generators (DFIGs) and series-compensated lines. There have been several papers focusing on the analysis of such SSR phenomenon. To the authors’ knowledge, the impacts of DFIG numbers are seldom considered in existing papers. In this paper, the impedance characteristics of DFIGs under different numbers are analyzed. Then the relationship between DFIG numbers and SSR characteristics is discussed. The contributions to be included in the paper are as following: 1) the impedance of N DFIGs is roughly equal to 1/N of the impedance of one DFIG. 2) The SSR risk of system is related with both the numbers of DFIGs and the parameters of the series-compensated lines.

Comparative assessment of genetic diversity in Sesamum indicum L. using RAPD and SSR markers.

Science.gov (United States)

Dar, Aejaz Ahmad; Mudigunda, Sushma; Mittal, Pramod Kumar; Arumugam, Neelakantan

2017-05-01

Sesame (Sesamum indicum L.) is an ancient oilseed crop known for its nutty seeds and high-quality edible oil. It is an unexplored crop with a great economic potential. The present study deals with assessment of genetic diversity in the crop. Twenty two RAPD and 18 SSR primers were used for analysis of the 47 different sesame accessions grown in different agroclimatic zones of India. A total of 256 bands were obtained with RAPD primers, of which 191 were polymorphic. SSR primers gave 64 DNA bands, of which all of were polymorphic. The Jaccard's similarity coefficient of RAPD, SSR, and pooled RAPD and SSR data ranged from 0.510 to 0.885, 0.167 to 0.867, and 0.505 to 0.853, respectively. Maximum polymorphic information content was reported with SSRs (0.194) compared to RAPDs (0.186). Higher marker index was observed with RAPDs (1.426) than with SSRs (0.621). Similarly, maximum resolving power was found with RAPD (4.012) primers than with SSRs (0.884). The RAPD primer RPI-B11 and SSR primer S16 were the most informative in terms of describing genetic variability among the varieties under study. At a molecular level, the seed coat colour was distinguishable by the presence and absence of a group of marker amplicon/s. White and brown seeded varieties clustered close to each other, while black seeded varieties remained distanced from the cluster. In the present study, we found higher variability in Sesamum indicum L. using RAPD and SSR markers and these could assist in DNA finger printing, conservation of germplasm, and crop improvement.

Assessment of genetic diversity in Brassica juncea Brassicaceae genotypes using phenotypic differences and SSR markers

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Vinu V.

2013-12-01

Full Text Available Las especies de mostaza del género Brassica representan uno de los cultivos de semillas oleaginosas más importantes en India, sin embargo, su diversidad genética es poco conocida. Para la utilización de genotipos en programas de cultivos resulta esencial un mayor conocimiento sobre este tema. Debido a ello, se evaluó la diversidad genética entre 44 genotipos de mostaza de la India Brassica juncea incluyendo variedades y líneas puras de diferentes zonas agro-climáticas de la India y algunos genotipos exóticos Australia, Polonia y China. Para ello, se utilizaron marcadores SSR específicos del genoma A y B y datos fenotípicos del rendimiento de 12 cosechas y sus características. De los 143 primers evaluados, 134 reportaron polimorfismo y un total de 355 alelos fueron amplificados. Se generaron dendrogramas a partir de los coeficientes de similitud de Jaccard y de disimilitud Manhattan, basados en un algoritmo de vinculación promedio UPGMA. Se utilizaron datos de marcadores genéticos y datos fenotípicos. Los genotipos se agruparon en cuatro grupos basados en las distancias genéticas. Ambos patrones de agrupamiento, tanto los basados en los coeficientes de similitud de Jaccard como los basados en los de disimilitud Manhattan, separaron independientemente los genotipos por su genealogía y origen, de una manera efectiva. El PCoA reveló que la agrupación de genotipos basada en datos de marcadores SSR, es más convincente que los datos fenotípicos, sin embargo, se observó que la correlación entre las matrices de distancia fenotípica y genética resultó muy baja r=0.11. Por lo tanto, para estudios de diversidad basados en marcadores moleculares es necesario realizar más pruebas. Los marcadores SSR constituyen herramientas más eficientes para discriminar entre genotipos de B. juncea, que las características cuantitativas.

Thermal hydraulic test of advanced fuel bundle with spectral shift rod (SSR) for BWR. Effect of thermal hydraulic parameters on steady state characteristics

International Nuclear Information System (INIS)

Kondo, Takao; Kitou, Kazuaki; Chaki, Masao; Ohga, Yukiharu; Makigami, Takeshi

2011-01-01

Japanese national project of next generation light water reactor (LWR) development started in 2008. Under this project, spectral shift rod (SSR) is being developed. SSR, which replaces conventional water rod (WR) of boiling water reactor (BWR) fuel bundle, was invented to enhance the BWR's merit, spectral shift effect for uranium saving. In SSR, water boils by neutron and gamma-ray direct heating and water level is formed as a boundary of the upper steam region and the lower water region. This SSR water level can be controlled by core flow rate, which amplifies the change of average core void fraction, resulting in the amplified spectral shift effect. This paper presents the steady state test results of the base geometry case in SSR thermal hydraulic test, which was conducted under the national project of next generation LWR. In the test, thermal hydraulic parameters, such as flow rate, pressure, inlet subcooling and heater rod power are changed to evaluate these effects on SSR water level and other SSR characteristics. In the test results, SSR water level rose as flow rate rose, which showed controllability of SSR water level by flow rate. The sensitivities of other thermal hydraulic parameters on SSR water level were also evaluated. The obtained data of parameter's sensitivities is various enough for the further analytical evaluation. The fluctuation of SSR water level was also measured to be small enough. As a result, it was confirmed that SSR's steady state performance was as planned and that SSR design concept is feasible. (author)

Transcriptomic analysis, genic SSR development, and genetic diversity of proso millet (Panicum miliaceum; Poaceae)1

Science.gov (United States)

Hou, Siyu; Sun, Zhaoxia; Li, Yaoshen; Wang, Yijie; Ling, Hubin; Xing, Guofang; Han, Yuanhuai; Li, Hongying

2017-01-01

Premise of the study: Proso millet (Panicum miliaceum; Poaceae) is a minor crop with good nutritional qualities and strong tolerance to drought stress and soil infertility. However, studies on genetic diversity have been limited due to a lack of efficient genetic markers. Methods: Illumina sequencing technology was used to generate short read sequences of proso millet, and de novo transcriptome assemblies were used to develop a de novo assembly of proso millet. Genic simple sequence repeat (SSR) markers were identified and used to detect polymorphism among 56 accessions. Population structure and genetic similarity coefficient were estimated. Results: In total, 25,341 unique gene sequences and 4724 SSR loci were obtained from the transcriptome, of which 229 pairs of SSR primers were validated, which resulted in 14 polymorphic genic SSR primers exhibiting 43 total alleles. According to the ratio of polymorphic markers (6.1%, 14/229), there are potentially 288 polymorphic genic SSR markers available for genetic assay development in the future. Bayesian population analyses showed that the 56 accessions comprised two distinct groups. Discussion: A genetic structure and cluster assay indicated that the accessions from the Loess Plateau of China shared a high genetic similarity coefficient with those from other regions and that there was no correlation between genetic diversity and geographic origin. The transcriptome sequencing data and millet-specific SSR markers developed in this study establish an excellent resource for gene discovery and may improve the development of breeding programs in proso millet in the future. PMID:28791202

78 FR 8217 - Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations...

Science.gov (United States)

2013-02-05

... SOCIAL SECURITY ADMINISTRATION [Docket No. SSA-2012-0071] Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations of Unfairness, Prejudice, Partiality, Bias... the third column, the fourth line under the ``Summary'' heading, change ``SSR-13-Xp'' to ``SSR-13-1p...

Development of simple sequence repeat markers and diversity analysis in alfalfa (Medicago sativa L.).

Science.gov (United States)

Wang, Zan; Yan, Hongwei; Fu, Xinnian; Li, Xuehui; Gao, Hongwen

2013-04-01

Efficient and robust molecular markers are essential for molecular breeding in plant. Compared to dominant and bi-allelic markers, multiple alleles of simple sequence repeat (SSR) markers are particularly informative and superior in genetic linkage map and QTL mapping in autotetraploid species like alfalfa. The objective of this study was to enrich SSR markers directly from alfalfa expressed sequence tags (ESTs). A total of 12,371 alfalfa ESTs were retrieved from the National Center for Biotechnology Information. Total 774 SSR-containing ESTs were identified from 716 ESTs. On average, one SSR was found per 7.7 kb of EST sequences. Tri-nucleotide repeats (48.8 %) was the most abundant motif type, followed by di-(26.1 %), tetra-(11.5 %), penta-(9.7 %), and hexanucleotide (3.9 %). One hundred EST-SSR primer pairs were successfully designed and 29 exhibited polymorphism among 28 alfalfa accessions. The allele number per marker ranged from two to 21 with an average of 6.8. The PIC values ranged from 0.195 to 0.896 with an average of 0.608, indicating a high level of polymorphism of the EST-SSR markers. Based on the 29 EST-SSR markers, assessment of genetic diversity was conducted and found that Medicago sativa ssp. sativa was clearly different from the other subspecies. The high transferability of those EST-SSR markers was also found for relative species.

Chromosomal location of genomic SSR markers associated

Indian Academy of Sciences (India)

Among the same earlier tested 230 primers, one SSR marker (Xgwm311) also amplified a fragment which is present in the resistant parent and in the resistant bulks, but absent in the susceptible parent and in the susceptible bulks. To understand the chromosome group location of these diagnostic markers, Xgwm382 and ...

An annotated genetic map of loblolly pine based on microsatellite and cDNA markers

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Wimalanathan Kokulapalan

2011-01-01

Full Text Available Abstract Background Previous loblolly pine (Pinus taeda L. genetic linkage maps have been based on a variety of DNA polymorphisms, such as AFLPs, RAPDs, RFLPs, and ESTPs, but only a few SSRs (simple sequence repeats, also known as simple tandem repeats or microsatellites, have been mapped in P. taeda. The objective of this study was to integrate a large set of SSR markers from a variety of sources and published cDNA markers into a composite P. taeda genetic map constructed from two reference mapping pedigrees. A dense genetic map that incorporates SSR loci will benefit complete pine genome sequencing, pine population genetics studies, and pine breeding programs. Careful marker annotation using a variety of references further enhances the utility of the integrated SSR map. Results The updated P. taeda genetic map, with an estimated genome coverage of 1,515 cM(Kosambi across 12 linkage groups, incorporated 170 new SSR markers and 290 previously reported SSR, RFLP, and ESTP markers. The average marker interval was 3.1 cM. Of 233 mapped SSR loci, 84 were from cDNA-derived sequences (EST-SSRs and 149 were from non-transcribed genomic sequences (genomic-SSRs. Of all 311 mapped cDNA-derived markers, 77% were associated with NCBI Pta UniGene clusters, 67% with RefSeq proteins, and 62% with functional Gene Ontology (GO terms. Duplicate (i.e., redundant accessory and paralogous markers were tentatively identified by evaluating marker sequences by their UniGene cluster IDs, clone IDs, and relative map positions. The average gene diversity, He, among polymorphic SSR loci, including those that were not mapped, was 0.43 for 94 EST-SSRs and 0.72 for 83 genomic-SSRs. The genetic map can be viewed and queried at http://www.conifergdb.org/pinemap. Conclusions Many polymorphic and genetically mapped SSR markers are now available for use in P. taeda population genetics, studies of adaptive traits, and various germplasm management applications. Annotating mapped

Physical location of SSR regions and cytogenetic instabilities in ...

Indian Academy of Sciences (India)

2014-08-18

Aug 18, 2014 ... RESEARCH NOTE. Physical location of SSR regions and cytogenetic instabilities in Pinus ... first cytogenetic study in Scots pine using SSRs in FISH experiments. ... Science, Mannheim, Germany) according to manufacturer's.

Development of genomic SSR and potential EST-SSR markers in ...

African Journals Online (AJOL)

PRECIOUS

2009-11-16

Nov 16, 2009 ... Institute of Medicinal Plant Development (IMPLAD), Chinese Academy of Medical Sciences (CAMS) and Peking .... from three sources of B. fatcatum in Taiwan (Liu et al., ..... Ministry of Finance People's Republic of China (No.

Tibiofemoral subchondral surface ratio (SSR) is a predictor of osteoarthritis symptoms and radiographic progression: data from the Osteoarthritis Initiative (OAI).

Science.gov (United States)

Everhart, J S; Siston, R A; Flanigan, D C

2014-06-01

Symptomatic knee osteoarthritis (OA) is poorly correlated with radiographic severity, but subchondral bone measures may be useful for risk assessment as bone shape is grossly unaffected at early radiographic stages. We sought to determine whether compartment-specific size mismatch in the naturally asymmetric tibiofemoral joint, measured as tibiofemoral subchondral surface ratio (SSR): (1) predicts incident symptoms, (2) predicts incident or progressive OA, (3) is reproducible and time invariant. OA Initiative participants with baseline MRIs and up to 48-month follow-up (n = 1,338) were analyzed. Logistic regression was used to determine the association between SSR and incident symptoms, incident OA, and progression of OA after adjusting for demographic, radiologic, injury-related, and lifestyle-related factors. Reproducibility was assessed as % coefficient of variation (CV) on repeat MRI studies at baseline and 24 months. Increased medial SSR is protective against incident symptoms at 48 months (per 0.1 increase: OR 0.48 CI 0.30, 0.75; P = 0.001). Increased lateral SSR values are protective against lateral OA incidence (OR 0.23 CI 0.06, 0.77; P = 0.016) or progression (OR 0.66 CI 0.43, 0.99; P = 0.049) at 24 months. Both medial and lateral SSR are stable over time (medial: mean change 0.001 SD 0.016; lateral: mean change 0.000 SD 0.017) and are highly reproducible (3.0% CV medial SSR; 2.7% CV lateral SSR). A larger medial SSR is protective against developing OA-related symptoms. A larger lateral SSR is protective against lateral OA incidence or progression. Finally, lateral and medial SSR are stable over time and are highly reproducible across MRI studies. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Development of Novel SSR Markers for Flax (Linum usitatissimum L.) Using Reduced-Representation Genome Sequencing.

Science.gov (United States)

Wu, Jianzhong; Zhao, Qian; Wu, Guangwen; Zhang, Shuquan; Jiang, Tingbo

2016-01-01

Flax ( Linum usitatissimum L.) is a major fiber and oil yielding crop grown in northeastern China. Identification of flax molecular markers is a key step toward improving flax yield and quality via marker-assisted breeding. Simple sequence repeat (SSR) markers, which are based on genomic structural variation, are considered the most valuable type of genetic marker for this purpose. In this study, we screened 1574 microsatellites from Linum usitatissimum L. obtained using reduced representation genome sequencing (RRGS) to systematically identify SSR markers. The resulting set of microsatellites consisted mainly of trinucleotide (56.10%) and dinucleotide (35.23%) repeats, with each motif consisting of 5-8 repeats. We then evaluated marker sensitivity and specificity based on samples of 48 flax isolates obtained from northeastern China. Using the new SSR panel, the results demonstrated that fiber flax and oilseed flax varieties clustered into two well separated groups. The novel SSR markers developed in this study show potential value for selection of varieties for use in flax breeding programs.

Genetic diversity of wild and cultivated Rubus species in Colombia using AFLP and SSR markers

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Sandra Bibiana Aguilar

2007-01-01

Full Text Available The Andean blackberry belongs to the genus Rubus, the largest of the Rosaceae family and one of the mostdiverse of the plant kingdom. In Colombia Rubus glaucus Benth, known as the Andean raspberry or blackberry, is one of thenine edible of the genus out of forty-four reported species. In this study wild and cultivated genotypes, collected in the CentralAndes of Colombia were analyzed by AFLP and SSR markers. Sexual reproduction seems to play an important role inmaintaining the genetic variability in R. glaucus, and the viability of using the SSR of Rubus alceifolius to characterizeColombian Rubus species was clearly demonstrated. All species evaluated produced very specific banding patterns,differentiating them from the others. Both AFLP and SSR produced bands exclusive to each of the following species: R.robustus, R. urticifolius, R. glaucus, and R. rosifolius. The SSR markers differentiated diploid and tetraploid genotypes of R.glaucus.

Development and characterization of genic SSR markers from low ...

Indian Academy of Sciences (India)

Development and characterization of genic SSR markers from low depth genome ... A variety of molecular markers are currently ... chloroform method (Sambrook et al. 1989). ..... Available online, http://www.iucnredlist.org/details/168255/0.

Phenotype- and SSR-Based Estimates of Genetic Variation between and within Two Important Elymus Species in Western and Northern China

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Zongyu Zhang

2018-03-01

Full Text Available Elymus nutans and Elymus sibiricus are two important perennial forage grasses of the genus Elymus, widely distributed in high altitude regions of Western and Northern China, especially on the Qinghai-Tibetan Plateau. Information on phenotypic and genetic diversity is limited, but necessary for Elymus germplasm collection, conservation, and utilization. In the present study, the phenotypic and genetic differentiation of 73 accessions of the two species were evaluated using 15 phenotypic traits and 40 expressed sequence tag derived simple sequence repeat markers (EST-SSRs. The results showed that only 7.23% phenotypic differentiation (Pst existed between the two Elymus species based on fifteen quantitative traits. Principal component analysis (PCA revealed that leaf traits, spike traits, and some seed traits were dominant factors in phenotypic variation. Moreover, 396 (97.8% and 331 (87.1% polymorphic bands were generated from 40 EST-SSR primers, suggesting high levels of genetic diversity for the two species. The highest genetic diversity was found in the Northeastern Qinghai-Tibetan Plateau groups. Clustering analysis based on molecular data showed that most accessions of each Elymus species tended to group together. Similar results were described by principal coordinates analysis (PCoA and structure analysis. The molecular variance analysis (AMOVA revealed that 81.47% and 89.32% variation existed within the geographical groups for the two species, respectively. Pearson’s correlation analyses showed a strong positive correlation between Nei’s genetic diversity and annual mean temperature. These results could facilitate Elymus germplasm collection, conservation, and future breeding.

Comparative evaluation of genetic diversity using RAPD, SSR and ...

Indian Academy of Sciences (India)

1Department of Molecular Biology and Genetic Engineering, 2Ranichauri Hill Campus, G. B. Pant University of Agriculture ... Comparison of RAPD, SSR and cytochrome P450 gene based markers, in terms of the ...... project programme.

Supplementary data: Development of SSR markers and construction ...

Indian Academy of Sciences (India)

Supplementary data: Development of SSR markers and construction of a linkage map in jute. Moumita Das, Sumana Banerjee, Raman Dhariwal, Shailendra Vyas, Reyazul R. Mir, Niladri Topdar, Avijit Kundu, Jitendra P. Khurana, Akhilesh K. Tyagi,. Debabrata Sarkar, Mohit K. Sinha, Harindra S. Balyan and Pushpendra K.

Genome size, cytogenetic data and transferability of EST-SSRs markers in wild and cultivated species of the genus Theobroma L. (Byttnerioideae, Malvaceae)

Science.gov (United States)

da Silva, Rangeline Azevedo; Souza, Gustavo; Lemos, Lívia Santos Lima; Lopes, Uilson Vanderlei; Patrocínio, Nara Geórgia Ribeiro Braz; Alves, Rafael Moysés; Marcellino, Lucília Helena; Clement, Didier; Micheli, Fabienne

2017-01-01

The genus Theobroma comprises several trees species native to the Amazon. Theobroma cacao L. plays a key economic role mainly in the chocolate industry. Both cultivated and wild forms are described within the genus. Variations in genome size and chromosome number have been used for prediction purposes including the frequency of interspecific hybridization or inference about evolutionary relationships. In this study, the nuclear DNA content, karyotype and genetic diversity using functional microsatellites (EST-SSR) of seven Theobroma species were characterized. The nuclear content of DNA for all analyzed Theobroma species was 1C = ~ 0.46 pg. These species presented 2n = 20 with small chromosomes and only one pair of terminal heterochromatic bands positively stained (CMA+/DAPI− bands). The small size of Theobroma ssp. genomes was equivalent to other Byttnerioideae species, suggesting that the basal lineage of Malvaceae have smaller genomes and that there was an expansion of 2C values in the more specialized family clades. A set of 20 EST-SSR primers were characterized for related species of Theobroma, in which 12 loci were polymorphic. The polymorphism information content (PIC) ranged from 0.23 to 0.65, indicating a high level of information per locus. Combined results of flow cytometry, cytogenetic data and EST-SSRs markers will contribute to better describe the species and infer about the evolutionary relationships among Theobroma species. In addition, the importance of a core collection for conservation purposes is highlighted. PMID:28187131

Genome size, cytogenetic data and transferability of EST-SSRs markers in wild and cultivated species of the genus Theobroma L. (Byttnerioideae, Malvaceae.

Directory of Open Access Journals (Sweden)

Rangeline Azevedo da Silva

Full Text Available The genus Theobroma comprises several trees species native to the Amazon. Theobroma cacao L. plays a key economic role mainly in the chocolate industry. Both cultivated and wild forms are described within the genus. Variations in genome size and chromosome number have been used for prediction purposes including the frequency of interspecific hybridization or inference about evolutionary relationships. In this study, the nuclear DNA content, karyotype and genetic diversity using functional microsatellites (EST-SSR of seven Theobroma species were characterized. The nuclear content of DNA for all analyzed Theobroma species was 1C = ~ 0.46 pg. These species presented 2n = 20 with small chromosomes and only one pair of terminal heterochromatic bands positively stained (CMA+/DAPI- bands. The small size of Theobroma ssp. genomes was equivalent to other Byttnerioideae species, suggesting that the basal lineage of Malvaceae have smaller genomes and that there was an expansion of 2C values in the more specialized family clades. A set of 20 EST-SSR primers were characterized for related species of Theobroma, in which 12 loci were polymorphic. The polymorphism information content (PIC ranged from 0.23 to 0.65, indicating a high level of information per locus. Combined results of flow cytometry, cytogenetic data and EST-SSRs markers will contribute to better describe the species and infer about the evolutionary relationships among Theobroma species. In addition, the importance of a core collection for conservation purposes is highlighted.

Exploiting BAC-end sequences for the mining, characterization and utility of new short sequences repeat (SSR) markers in Citrus.

Science.gov (United States)

Biswas, Manosh Kumar; Chai, Lijun; Mayer, Christoph; Xu, Qiang; Guo, Wenwu; Deng, Xiuxin

2012-05-01

The aim of this study was to develop a large set of microsatellite markers based on publicly available BAC-end sequences (BESs), and to evaluate their transferability, discriminating capacity of genotypes and mapping ability in Citrus. A set of 1,281 simple sequence repeat (SSR) markers were developed from the 46,339 Citrus clementina BAC-end sequences (BES), of them 20.67% contained SSR longer than 20 bp, corresponding to roughly one perfect SSR per 2.04 kb. The most abundant motifs were di-nucleotide (16.82%) repeats. Among all repeat motifs (TA/AT)n is the most abundant (8.38%), followed by (AG/CT)n (4.51%). Most of the BES-SSR are located in the non-coding region, but 1.3% of BES-SSRs were found to be associated with transposable element (TE). A total of 400 novel SSR primer pairs were synthesized and their transferability and polymorphism tested on a set of 16 Citrus and Citrus relative's species. Among these 333 (83.25%) were successfully amplified and 260 (65.00%) showed cross-species transferability with Poncirus trifoliata and Fortunella sp. These cross-species transferable markers could be useful for cultivar identification, for genomic study of Citrus, Poncirus and Fortunella sp. Utility of the developed SSR marker was demonstrated by identifying a set of 118 markers each for construction of linkage map of Citrus reticulata and Poncirus trifoliata. Genetic diversity and phylogenetic relationship among 40 Citrus and its related species were conducted with the aid of 25 randomly selected SSR primer pairs and results revealed that citrus genomic SSRs are superior to genic SSR for genetic diversity and germplasm characterization of Citrus spp.

Identification, characterization and utilization of unigene derived microsatellite markers in tea (Camellia sinensis L.

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Mohapatra Trilochan

2009-05-01

Full Text Available Abstract Background Despite great advances in genomic technology observed in several crop species, the availability of molecular tools such as microsatellite markers has been limited in tea (Camellia sinensis L.. The development of microsatellite markers will have a major impact on genetic analysis, gene mapping and marker assisted breeding. Unigene derived microsatellite (UGMS markers identified from publicly available sequence database have the advantage of assaying variation in the expressed component of the genome with unique identity and position. Therefore, they can serve as efficient and cost effective alternative markers in such species. Results Considering the multiple advantages of UGMS markers, 1,223 unigenes were predicted from 2,181 expressed sequence tags (ESTs of tea (Camellia sinensis L.. A total of 109 (8.9% unigenes containing 120 SSRs were identified. SSR abundance was one in every 3.55 kb of EST sequences. The microsatellites mainly comprised of di (50.8%, tri (30.8%, tetra (6.6%, penta (7.5% and few hexa (4.1% nucleotide repeats. Among the dinucleotide repeats, (GAn.(TCn were most abundant (83.6%. Ninety six primer pairs could be designed form 83.5% of SSR containing unigenes. Of these, 61 (63.5% primer pairs were experimentally validated and used to investigate the genetic diversity among the 34 accessions of different Camellia spp. Fifty one primer pairs (83.6% were successfully cross transferred to the related species at various levels. Functional annotation of the unigenes containing SSRs was done through gene ontology (GO characterization. Thirty six (60% of them revealed significant sequence similarity with the known/putative proteins of Arabidopsis thaliana. Polymorphism information content (PIC ranged from 0.018 to 0.972 with a mean value of 0.497. The average heterozygosity expected (HE and observed (Ho obtained was 0.654 and 0.413 respectively, thereby suggesting highly heterogeneous nature of tea. Further, test

galaxieEST: addressing EST identity through automated phylogenetic analysis.

Science.gov (United States)

Nilsson, R Henrik; Rajashekar, Balaji; Larsson, Karl-Henrik; Ursing, Björn M

2004-07-05

Research involving expressed sequence tags (ESTs) is intricately coupled to the existence of large, well-annotated sequence repositories. Comparatively complete and satisfactory annotated public sequence libraries are, however, available only for a limited range of organisms, rendering the absence of sequences and gene structure information a tangible problem for those working with taxa lacking an EST or genome sequencing project. Paralogous genes belonging to the same gene family but distinguished by derived characteristics are particularly prone to misidentification and erroneous annotation; high but incomplete levels of sequence similarity are typically difficult to interpret and have formed the basis of many unsubstantiated assumptions of orthology. In these cases, a phylogenetic study of the query sequence together with the most similar sequences in the database may be of great value to the identification process. In order to facilitate this laborious procedure, a project to employ automated phylogenetic analysis in the identification of ESTs was initiated. galaxieEST is an open source Perl-CGI script package designed to complement traditional similarity-based identification of EST sequences through employment of automated phylogenetic analysis. It uses a series of BLAST runs as a sieve to retrieve nucleotide and protein sequences for inclusion in neighbour joining and parsimony analyses; the output includes the BLAST output, the results of the phylogenetic analyses, and the corresponding multiple alignments. galaxieEST is available as an on-line web service for identification of fungal ESTs and for download / local installation for use with any organism group at http://galaxie.cgb.ki.se/galaxieEST.html. By addressing sequence relatedness in addition to similarity, galaxieEST provides an integrative view on EST origin and identity, which may prove particularly useful in cases where similarity searches return one or more pertinent, but not full, matches and

GENETIC DIVERSITY OF S3 MAIZE GENOTYPES RESISTANT TO DOWNY MILDEW BASED ON SSR MARKERS

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Amran Muis

2016-02-01

Full Text Available The compulsory requirement for releasing new high yielding maize varieties is resistance to downy mildew. The study aimed to determine the level of homozygosity, genetic diversity, and  genetic distance of 30 S3 genotypes of maize. Number of primers to be used were 30 polymorphic SSR loci which are distributed over the entire maize genomes. The S3 genotypes used were resistant to downy mildew with homozygosity level of >80%, genetic distance between the test and tester strains >0.7, and anthesis silking interval (ASI between inbred lines and tester lines was maximum 3 days. The results showed that 30 SSR primers used were spread evenly across the maize genomes which were manifested in the representation of SSR loci on each chromosome of a total of 10 chromosomes. The levels of polymorphism ranged from 0.13 to 0.78, an average of 0.51, and the number of alleles ranged from 2 to 8 alleles per SSR locus, an average of 4 alleles per SSR locus. The size of nucleotides in each locus also varied from 70 to 553 bp. Cophenetic correlation value (r at 0.67 indicated that the Unweighted Pair-Group Method Using Arithmetic Averages (UPGMA was less reliable for differentiating genotypes in five groups. Of the total of 30 genotypes analyzed, 17 genotypes had homozygosity level of >80% so it can be included in the hybrid assembly program.

SSR marker variations in Brassica species provide insight into the origin and evolution of Brassica amphidiploids.

Science.gov (United States)

Thakur, Ajay Kumar; Singh, Kunwar Harendra; Singh, Lal; Nanjundan, Joghee; Khan, Yasin Jeshima; Singh, Dhiraj

2018-01-01

Oilseed Brassica represents an important group of oilseed crops with a long history of evolution and cultivation. To understand the origin and evolution of Brassica amphidiploids, simple sequence repeat (SSR) markers were used to unravel genetic variations in three diploids and three amphidiploid Brassica species of U's triangle along with Eruca sativa as an outlier. Of 124 Brassica-derived SSR loci assayed, 100% cross-transferability was obtained for B. juncea and three subspecies of B. rapa , while lowest cross-transferability (91.93%) was obtained for Eruca sativa . The average % age of cross-transferability across all the seven species was 98.15%. The number of alleles detected at each locus ranged from one to six with an average of 3.41 alleles per primer pair. Neighbor-Joining-based dendrogram divided all the 40 accessions into two main groups composed of B. juncea / B. nigra/B. rapa and B. carinata/B. napus/B. oleracea . C-genome of oilseed Brassica species remained relatively more conserved than A- and B-genome. A- genome present in B. juncea and B. napus seems distinct from each other and hence provides great opportunity for generating diversity through synthesizing amphidiploids from different sources of A- genome. B. juncea had least intra-specific distance indicating narrow genetic base. B. rapa appears to be more primitive species from which other two diploid species might have evolved. The SSR marker set developed in this study will assist in DNA fingerprinting of various Brassica species cultivars, evaluating the genetic diversity in Brassica germplasm, genome mapping and construction of linkage maps, gene tagging and various other genomics-related studies in Brassica species. Further, the evolutionary relationship established among various Brassica species would assist in formulating suitable breeding strategies for widening the genetic base of Brassica amphidiploids by exploiting the genetic diversity present in diploid progenitor gene pools.

Genetic variation assessment of acid lime accessions collected from south of Iran using SSR and ISSR molecular markers.

Science.gov (United States)

Sharafi, Ata Allah; Abkenar, Asad Asadi; Sharafi, Ali; Masaeli, Mohammad

2016-01-01

Iran has a long history of acid lime cultivation and propagation. In this study, genetic variation in 28 acid lime accessions from five regions of south of Iran, and their relatedness with other 19 citrus cultivars were analyzed using Simple Sequence Repeat (SSR) and Inter-Simple Sequence Repeat (ISSR) molecular markers. Nine primers for SSR and nine ISSR primers were used for allele scoring. In total, 49 SSR and 131 ISSR polymorphic alleles were detected. Cluster analysis of SSR and ISSR data showed that most of the acid lime accessions (19 genotypes) have hybrid origin and genetically distance with nucellar of Mexican lime (9 genotypes). As nucellar of Mexican lime are susceptible to phytoplasma, these acid lime genotypes can be used to evaluate their tolerance against biotic constricts like lime "witches' broom disease".

Simple sequence repeat (SSR)-based genetic variability among ...

African Journals Online (AJOL)

The objective of this study was to compare if simple sequence repeat (SSR) markers could correctly identify peanut genotypes with difference in specific leaf weight (SLW) and relative water content (RWC). Four peanut genotypes and two water regimes (FC and 1/3 available water; 1/3 AW) were arranged in factorial ...

Insight into the genetic variability analysis and cultivar identification of tall fescue by using SSR markers.

Science.gov (United States)

Fu, Kaixin; Guo, Zhihui; Zhang, Xinquan; Fan, Yan; Wu, Wendan; Li, Daxu; Peng, Yan; Huang, Linkai; Sun, Ming; Bai, Shiqie; Ma, Xiao

2016-01-01

Genetic diversity of 19 forage-type and 2 turf-type cultivars of tall fescue ( Festuca arundinacea Schreb.) was revealed using SSR markers in an attempt to explore the genetic relationships among them, and examine potential use of SSR markers to identify cultivars by bulked samples. A total of 227 clear band was scored with 14 SSR primers and out of which 201 (88.6 %) were found polymorphic. The percentage of polymorphic bands (PPB) per primer pair varied from 62.5 to 100 % with an average of 86.9 %. The polymorphism information content (PIC) value ranged from 0.116 to 0.347 with an average of 0.257 and the highest PIC value (0.347) was noticed for primer NFA040 followed by NFA113 (0.346) whereas the highest discriminating power (D) of 1 was shown in NFA037 and LMgSSR02-01C. A Neighbor-joining dendrogram and the principal component analysis identified six major clusters and grouped the cultivars in agreement with their breeding histories. STRUCTURE analysis divided these cultivars into 3 sub-clades which correspond to distance based groupings. These findings indicates that SSR markers by bulking strategy are a useful tool to measure genetic diversity among tall fescue cultivars and could be used to supplement morphological data for plant variety protection.

Molecular diversity and phylogeny of Triticum-Aegilops species possessing D genome revealed by SSR and ISSR markers

Directory of Open Access Journals (Sweden)

Moradkhani Hoda

2015-12-01

Full Text Available The aim of this study is investigation the applicability of SSR and ISSR markers in evaluating the genetic relationships in twenty accessions of Aegilops and Triticum species with D genome in different ploidy levels. Totally, 119 bands and 46 alleles were detected using ten primers for ISSR and SSR markers, respectively. Polymorphism Information Content values for all primers ranged from 0.345 to 0.375 with an average of 0.367 for SSR, and varied from 0.29 to 0.44 with the average 0.37 for ISSR marker. Analysis of molecular variance (AMOVA revealed that 81% (ISSR and 84% (SSR of variability was partitioned among individuals within populations. Comparing the genetic diversity of Aegilops and Triticum accessions, based on genetic parameters, shows that genetic variation of Ae. crassa and Ae. tauschii species are higher than other species, especially in terms of Nei’s gene diversity. Cluster analysis, based on both markers, separated total accessions in three groups. However, classification based on SSR marker data was not conformed to classification according to ISSR marker data. Principal co-ordinate analysis (PCoA for SSR and ISSR data showed that, the first two components clarified 53.48% and 49.91% of the total variation, respectively. This analysis (PCoA, also, indicated consistent patterns of genetic relationships for ISSR data sets, however, the grouping of accessions was not completely accorded to their own geographical origins. Consequently, a high level of genetic diversity was revealed from the accessions sampled from different eco-geographical regions of Iran.

Characterization of novel SSR markers in diverse sainfoin (Onobrychis viciifolia) germplasm.

Science.gov (United States)

Kempf, Katharina; Mora-Ortiz, Marina; Smith, Lydia M J; Kölliker, Roland; Skøt, Leif

2016-08-30

Sainfoin is a perennial forage legume with beneficial properties for animal husbandry due to the presence of secondary metabolites. However, worldwide cultivation of sainfoin is marginal due to the lack of varieties with good agronomic performance, adapted to a broad range of environmental conditions. Little is known about the genetics of sainfoin and only few genetic markers are available to assist breeding and genetic investigations. The objective of this study was to develop a set of SSR markers useful for genetic studies in sainfoin and their characterization in diverse germplasm. A set of 400 SSR primer combinations were tested for amplification and their ability to detect polymorphisms in a set of 32 sainfoin individuals, representing distinct varieties or landraces. Alleles were scored for presence or absence and polymorphism information content of each SSR locus was calculated with an adapted formula taking into account the tetraploid character of sainfoin. Relationships among individuals were visualized using cluster and principle components analysis. Of the 400 primer combinations tested, 101 reliably detected polymorphisms among the 32 sainfoin individuals. Among the 1154 alleles amplified 250 private alleles were observed. The number of alleles per locus ranged from 2 to 24 with an average of 11.4 alleles. The average polymorphism information content reached values of 0.14 to 0.36. The clustering of the 32 individuals suggested a separation into two groups depending on the origin of the accessions. The SSR markers characterized and tested in this study provide a valuable tool to detect polymorphisms in sainfoin for future genetic studies and breeding programs. As a proof of concept, we showed that these markers can be used to separate sainfoin individuals based on their origin.

SSR

African Journals Online (AJOL)

RAJU

2013-07-24

Jul 24, 2013 ... bioinformatics tools for development of genic molecular markers is, therefore, crucial in this phase. This mini-review mainly ... cing, EST generation and analysis has resulted in the .... SNP discovery from EST sequences include clustering, sequence ...... Integrated with Primer Design and PCR Simulation.

Genetic variation and DNA fingerprinting of durian types in Malaysia using simple sequence repeat (SSR) markers.

Science.gov (United States)

Siew, Ging Yang; Ng, Wei Lun; Tan, Sheau Wei; Alitheen, Noorjahan Banu; Tan, Soon Guan; Yeap, Swee Keong

2018-01-01

Durian ( Durio zibethinus ) is one of the most popular tropical fruits in Asia. To date, 126 durian types have been registered with the Department of Agriculture in Malaysia based on phenotypic characteristics. Classification based on morphology is convenient, easy, and fast but it suffers from phenotypic plasticity as a direct result of environmental factors and age. To overcome the limitation of morphological classification, there is a need to carry out genetic characterization of the various durian types. Such data is important for the evaluation and management of durian genetic resources in producing countries. In this study, simple sequence repeat (SSR) markers were used to study the genetic variation in 27 durian types from the germplasm collection of Universiti Putra Malaysia. Based on DNA sequences deposited in Genbank, seven pairs of primers were successfully designed to amplify SSR regions in the durian DNA samples. High levels of variation among the 27 durian types were observed (expected heterozygosity, H E  = 0.35). The DNA fingerprinting power of SSR markers revealed by the combined probability of identity (PI) of all loci was 2.3×10 -3 . Unique DNA fingerprints were generated for 21 out of 27 durian types using five polymorphic SSR markers (the other two SSR markers were monomorphic). We further tested the utility of these markers by evaluating the clonal status of shared durian types from different germplasm collection sites, and found that some were not clones. The findings in this preliminary study not only shows the feasibility of using SSR markers for DNA fingerprinting of durian types, but also challenges the current classification of durian types, e.g., on whether the different types should be called "clones", "varieties", or "cultivars". Such matters have a direct impact on the regulation and management of durian genetic resources in the region.

Identification of SSR and RAPD markers linked to a resistance allele for angular leaf spot in the common bean (Phaseolus vulgaris line ESAL 550

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Gilvan Ferreira da Silva

2003-12-01

Full Text Available The objective of this study was to identify RAPD and SSR markers associated with a resistant allele for angular leaf spot (Phaeoisariopsis griseola from the line 'ESAL 550', derived from the Andean 'Jalo EEP 558' cultivar, to assist selection of resistant genotypes. The resistant line 'ESAL 550' and the susceptible cultivar 'Carioca MG' were crossed to generate F1 and F2 populations. One hundred and twenty F2:3 families were evaluated. The DNA of the 12 most resistant families was bulked and the same was done with the DNA of the 10 most susceptible, generating two contrasting bulks. One RAPD and one SSR marker was found to be linked in coupling phase to the resistant allele. The SSR marker was amplified by the primer PV-atct001(282C, and its distance from the resistant allele was 7.6 cM. This is the most useful marker for indirect selection of resistant plants in segregating populations. The RAPD marker was amplified by the primer OPP07(857C linked in coupling phase to the resistant allele, and distant 24.4 cM. Therefore, this RAPD marker is not so useful in assisting selection because it is too far from the resistant allele.

Molecular genetic diversity assessment of Citrus species grown in Iran revealed by SSR, ISSR and CAPS molecular markers

Directory of Open Access Journals (Sweden)

Ata Allah Sharafi

2017-12-01

Full Text Available In this study, genetic diversity in 19 citrus cultivars was analyzed using Simple Sequence Repeat (SSR, Inter-simple Sequence Repeat (ISSR and cleaved amplified polymorphic sequence (CAPS markers. Nine primers for SSR, nine ISSR primers and two primers for CAPS were used for allele scoring. One chloroplast DNA region (rbcL-ORF106 and one mitochondrial DNA region (18S-5S were analyzed using cleaved amplified polymorphic sequence (CAPS marker in 19 citrus accessions grown in Iran. In total, 45 SSR and 131 ISSR polymorphic alleles and tree organelle genome types were detected. Cluster analysis of SSR and ISSR data was performed using UPGMA method and based on Jaccard's coefficient. The result of this investigation showed that the SSR and ISSR primers were highly informative and efficient in detecting genetic variability and relationships of the citrus accessions. And CAPS marker analysis Results showed that Bakraee and one of off type Mexican lime had banding pattern similar to Clementine Mandarin, while Pummelo regarded as maternal parent of other studied genotypes Citron regarded as father parent showed definite banding pattern among 19 studied genotypes which it confirmed Cytoplasmic inheritance from mother cellular organelles.

Molecular breeding in Brassica for salt tolerance: importance of microsatellite (SSR) markers for molecular breeding in Brassica.

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Kumar, Manu; Choi, Ju-Young; Kumari, Nisha; Pareek, Ashwani; Kim, Seong-Ryong

2015-01-01

Salinity is one of the important abiotic factors for any crop management in irrigated as well as rainfed areas, which leads to poor harvests. This yield reduction in salt affected soils can be overcome by improving salt tolerance in crops or by soil reclamation. Salty soils can be reclaimed by leaching the salt or by cultivation of salt tolerance crops. Salt tolerance is a quantitative trait controlled by several genes. Poor knowledge about mechanism of its inheritance makes slow progress in its introgression into target crops. Brassica is known to be a good reclamation crop. Inter and intra specific variation within Brassica species shows potential of molecular breeding to raise salinity tolerant genotypes. Among the various molecular markers, SSR markers are getting high attention, since they are randomly sparsed, highly variable and show co-dominant inheritance. Furthermore, as sequencing techniques are improving and softwares to find SSR markers are being developed, SSR markers technology is also evolving rapidly. Comparative SSR marker studies targeting Arabidopsis thaliana and Brassica species which lie in the same family will further aid in studying the salt tolerance related QTLs and subsequent identification of the "candidate genes" and finding out the origin of important QTLs. Although, there are a few reports on molecular breeding for improving salt tolerance using molecular markers in Brassica species, usage of SSR markers has a big potential to improve salt tolerance in Brassica crops. In order to obtain best harvests, role of SSR marker driven breeding approaches play important role and it has been discussed in this review especially for the introgression of salt tolerance traits in crops.

Molecular breeding in Brassica for salt tolerance: importance of microsatellite (SSR) markers for molecular breeding in Brassica

Science.gov (United States)

Kumar, Manu; Choi, Ju-Young; Kumari, Nisha; Pareek, Ashwani; Kim, Seong-Ryong

2015-01-01

Salinity is one of the important abiotic factors for any crop management in irrigated as well as rainfed areas, which leads to poor harvests. This yield reduction in salt affected soils can be overcome by improving salt tolerance in crops or by soil reclamation. Salty soils can be reclaimed by leaching the salt or by cultivation of salt tolerance crops. Salt tolerance is a quantitative trait controlled by several genes. Poor knowledge about mechanism of its inheritance makes slow progress in its introgression into target crops. Brassica is known to be a good reclamation crop. Inter and intra specific variation within Brassica species shows potential of molecular breeding to raise salinity tolerant genotypes. Among the various molecular markers, SSR markers are getting high attention, since they are randomly sparsed, highly variable and show co-dominant inheritance. Furthermore, as sequencing techniques are improving and softwares to find SSR markers are being developed, SSR markers technology is also evolving rapidly. Comparative SSR marker studies targeting Arabidopsis thaliana and Brassica species which lie in the same family will further aid in studying the salt tolerance related QTLs and subsequent identification of the “candidate genes” and finding out the origin of important QTLs. Although, there are a few reports on molecular breeding for improving salt tolerance using molecular markers in Brassica species, usage of SSR markers has a big potential to improve salt tolerance in Brassica crops. In order to obtain best harvests, role of SSR marker driven breeding approaches play important role and it has been discussed in this review especially for the introgression of salt tolerance traits in crops. PMID:26388887

Analysis of genetic stability at SSR loci during somatic embryogenesis in maritime pine (Pinus pinaster).

Science.gov (United States)

Marum, Liliana; Rocheta, Margarida; Maroco, João; Oliveira, M Margarida; Miguel, Célia

2009-04-01

Somatic embryogenesis (SE) is a propagation tool of particular interest for accelerating the deployment of new high-performance planting stock in multivarietal forestry. However, genetic conformity in in vitro propagated plants should be assessed as early as possible, especially in long-living trees such as conifers. The main objective of this work was to study such conformity based on genetic stability at simple sequence repeat (SSR) loci during somatic embryogenesis in maritime pine (Pinus pinaster Ait.). Embryogenic cell lines (ECLs) subjected to tissue proliferation during 6, 14 or 22 months, as well as emblings regenerated from several ECLs, were analyzed. Genetic variation at seven SSR loci was detected in ECLs under proliferation conditions for all time points, and in 5 out of 52 emblings recovered from somatic embryos. Three of these five emblings showed an abnormal phenotype consisting mainly of plagiotropism and loss of apical dominance. Despite the variation found in somatic embryogenesis-derived plant material, no correlation was established between genetic stability at the analyzed loci and abnormal embling phenotype, present in 64% of the emblings. The use of microsatellites in this work was efficient for monitoring mutation events during the somatic embryogenesis in P. pinaster. These molecular markers should be useful in the implementation of new breeding and deployment strategies for improved trees using SE.

LSGermOPA, a custom OPA of 384 EST-derived SNPs for high-throughput lettuce (Lactuca sativa L.) germplasm fingerprinting

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We assessed the genetic diversity and population structure among 148 cultivated lettuce (Lactuca sativa L.) accessions using the high-throughput GoldenGate assay and 384 EST (Expressed Sequence Tag)-derived SNP (single nucleotide polymorphism) markers. A custom OPA (Oligo Pool All), LSGermOPA was fo...

Analysis of esterase isozyme and SSR for mutagenic progenies induced by space mutation in mustard

International Nuclear Information System (INIS)

Shen Jinjuan; Liu Yihua; Zhang Zhaorong; Ran Guangkui; Zhao Shouzhong; Xiao Li

2012-01-01

Seeds of five mustard (Brassica juncea Coss) varieties were carried into outer space by 'Shijian No.8' satellite. After five years' consecutive planting and selection, ten relatively stable mutant lines were obtained, which had significant variation in agronomic and economic characters. The mutant lines and their original varieties without space mutation treatment as control were studied by esterase isozyme and SSR analyses. Electrophoresis analysis of esterase isozymes indicated that there were differences between mutant lines and their controls in enzyme types and enzyme activity. Different mustard varieties had different enzymographs, and so did the mutants induced by space mutation, which shows different sensitivity among different mustard varieties. The SSR analysis showed that large differences were found in the SSR loci between mutant lines and their original variety, the variation frequency was between 9.52% and 57.14% with an average frequency of 26.19% for all the mutant lines. Among the mutant SSR loci, about 56.36% showed changes in band number and 43.64% in molecular weight. These results indicated that the ten mutant lines had large genetic difference in phenotype, genomic sequence and gene expression, and the outer space mutation would be an effective method to develop new mustard germplasm and variety. (authors)

Genome-wide analysis of SSR and ILP markers in trees: diversity profiling, alternate distribution, and applications in duplication.

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Xia, Xinyao; Luan, Lin Lin; Qin, Guanghua; Yu, Li Fang; Wang, Zhi Wei; Dong, Wan Chen; Song, Yumin; Qiao, Yuling; Zhang, Xian Sheng; Sang, Ya Lin; Yang, Long

2017-12-20

Molecular markers are efficient tools for breeding and genetic studies. However, despite their ecological and economic importance, their development and application have long been hampered. In this study, we identified 524,170 simple sequence repeat (SSR), 267,636 intron length polymorphism (ILP), and 11,872 potential intron polymorphism (PIP) markers from 16 tree species based on recently available genome sequences. Larger motifs, including hexamers and heptamers, accounted for most of the seven different types of SSR loci. Within these loci, A/T bases comprised a significantly larger proportion of sequence than G/C. SSR and ILP markers exhibited an alternative distribution pattern. Most SSRs were monomorphic markers, and the proportions of polymorphic markers were positively correlated with genome size. By verifying with all 16 tree species, 54 SSR, 418 ILP, and four PIP universal markers were obtained, and their efficiency was examined by PCR. A combination of five SSR and six ILP markers were used for the phylogenetic analysis of 30 willow samples, revealing a positive correlation between genetic diversity and geographic distance. We also found that SSRs can be used as tools for duplication analysis. Our findings provide important foundations for the development of breeding and genetic studies in tree species.

Development of a simple sequence repeat (SSR) marker set to ...

African Journals Online (AJOL)

GREGORY

2010-08-23

Aug 23, 2010 ... varieties. Tuber seeds of most of these varieties are not produced and distributed in an organized way ... races from Canary Islands using 19 SSR markers. The ... The aim of the current study was to determine a set of.

The Non-Peptide Vasopressin V1b Receptor Antagonist, SSR149415, Ameliorates Spermatogenesis Function in a Mouse Model of Chronic Social Defeat Stress.

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Wang, Bin; Zhou, Jian; Zhuang, Yan-Yan; Wang, Liang-Liang; Pu, Jin-Xian; Huang, Yu-Hua; Xia, Fei; Lv, Jin-Xing

2017-11-01

To determine the effects of SSR149415 on testis and spermatogenesis in male mice subjected to chronic social defeat stress, C57BL/6 male mice were divided into two groups: Control and Stress. Then Stress group was subdivided into four subgroups administered water, SSR149415 (1 mg/kg/day), SSR149415 (10 mg/kg/day), SSR149415 (30 mg/kg/day), respectively. The behavioral alterations revealed by social interaction test and open field test were measured. The physical indices, including body weight and gonad weight (testis and epididymis) as well as testis/body weight and cauda epididymis/body weight were detected. Serum hormones, including testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were determined. Sperm count and abnormality as well as testicular histology structure were assessed. The germ cells apoptosis were also evaluated. Chronic social defeat stress-induced behavioral abnormality, as well as gonad atrophy (testis and epididymis) was significantly alleviated in stressed male mice exposed to SSR149415. Regressed serum testosterone levels and elevated serum FSH and LH levels exhibited by stressed male mice were observably reversed following SSR149415 administration. Chronic social defeat stress-induced damage in testicular histology structure and semen quality were also improved after SSR149415 administration. In addition, SSR149415 significantly reversed chronic social defeat stress-induced germ cells apoptosis. Overall, we provide clear evidence indicating the amelioration of chronic social defeat stress-induced behavioral abnormality and testicular dysfunction via SSR149415, promoting the development of drug-directed therapy against this disease. J. Cell. Biochem. 118: 3891-3898, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Confamiliar transferability of simple sequence repeat (SSR) markers from cotton (Gossypium hirsutum L.) and jute (Corchorus olitorius L.) to twenty two Malvaceous species.

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Satya, Pratik; Paswan, Pramod Kumar; Ghosh, Swagata; Majumdar, Snehalata; Ali, Nasim

2016-06-01

Cross-species transferability is a quick and economic method to enrich SSR database, particularly for minor crops where little genomic information is available. However, transferability of SSR markers varies greatly between species, genera and families of plant species. We assessed confamiliar transferability of SSR markers from cotton (Gossypium hirsutum) and jute (Corchorus olitorius) to 22 species distributed in different taxonomic groups of Malvaceae. All the species selected were potential industrial crop species having little or no genomic resources or SSR database. Of the 14 cotton SSR loci tested, 13 (92.86 %) amplified in G. arboreum and 71.43 % exhibited cross-genera transferability. Nine out of 11 jute SSRs (81.81 %) showed cross-transferability across genera. SSRs from both the species exhibited high polymorphism and resolving power in other species. The correlation between transferability of cotton and jute SSRs were highly significant (r = 0.813). The difference in transferability among species was also significant for both the marker groups. High transferability was observed at genus, tribe and subfamily level. At tribe level, transferability of jute SSRs (41.04 %) was higher than that of cotton SSRs (33.74 %). The tribe Byttnerieae exhibited highest SSR transferability (48.7 %). The high level of cross-genera transferability (>50 %) in ten species of Malvaceae, where no SSR resource is available, calls for large scale transferability testing from the enriched SSR databases of cotton and jute.

RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

International Nuclear Information System (INIS)

Wang Tiegu; Huang Qunce; Feng Weisen

2007-01-01

Two types of markers-random amplified polymorphic DNA (RAPD) and simple sequence repeat DNA (SSR)-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA (Unweighted Pair-group Method with Arithmetic averaging) algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, s1, opt-16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 (Xgwm261), Rht-B1b, and Rht-D1b, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning

RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

Science.gov (United States)

Wang, Tiegu; Huang, Qunce; Feng, Weisen

2007-10-01

Two types of markers-random amplified polymorphic DNA (RAPD) and simple sequence repeat DNA (SSR)-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA (Unweighted Pair-group Method with Arithmetic averaging) algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, s1, opt-16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 (Xgwm261), Rht-B1b, and Rht-D1b, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning.

RAPD and SSR Polymorphisms in Mutant Lines of Transgenic Wheat Mediated by Low Energy Ion Beam

Energy Technology Data Exchange (ETDEWEB)

Tiegu, Wang [Henan Provincial Key Laboratory of Ion Beam Bio-Engineering, Zhengzhou University, Zhengzhou 450052 (China); Qunce, Huang [Henan Provincial Key Laboratory of Ion Beam Bio-Engineering, Zhengzhou University, Zhengzhou 450052 (China); Weisen, Feng [Luoyang Institute of Agricultural Science, Luoyang 471022 (China)

2007-10-15

Two types of markers-random amplified polymorphic DNA (RAPD) and simple sequence repeat DNA (SSR)-have been used to characterize the genetic diversity among nine mutant lines of transgenic wheat intermediated by low energy ion beam and their four receptor cultivars. The objectives of this study were to analyze RAPD-based and SSR-based genetic variance among transgenic wheat lines and with their receptors, and to find specific genetic markers of special traits of transgenic wheat lines. 170 RAPD primers were amplified to 733 fragments in all the experimental materials. There were 121 polymorphic fragments out of the 733 fragments with a ratio of polymorphic fragments of 16.5%. 29 SSR primer pairs were amplified to 83 fragments in all the experiment materials. There were 57 polymorphic fragments out of the 83 fragments with a ratio of polymorphic fragments of 68.7%. The dendrograms were prepared based on a genetic distance matrix using the UPGMA (Unweighted Pair-group Method with Arithmetic averaging) algorithm, which corresponded well to the results of the wheat pedigree analysis and separated the 13 genotypes into four groups. Association analysis between RAPD and SSR markers with the special traits of transgenic wheat mutant lines discovered that three RAPD markers, s1, opt-16, and f14, were significantly associated with the muticate trait, while three SSR markers, Rht8 (Xgwm261), Rht-B1b, and Rht-D1b, highly associated with the dwarf trait. These markers will be useful for marker-assistant breeding and can be used as candidate markers for further gene mapping and cloning.

Development of genic-SSR markers by deep transcriptome sequencing in pigeonpea [Cajanus cajan (L.) Millspaugh

Science.gov (United States)

2011-01-01

Background Pigeonpea [Cajanus cajan (L.) Millspaugh], one of the most important food legumes of semi-arid tropical and subtropical regions, has limited genomic resources, particularly expressed sequence based (genic) markers. We report a comprehensive set of validated genic simple sequence repeat (SSR) markers using deep transcriptome sequencing, and its application in genetic diversity analysis and mapping. Results In this study, 43,324 transcriptome shotgun assembly unigene contigs were assembled from 1.696 million 454 GS-FLX sequence reads of separate pooled cDNA libraries prepared from leaf, root, stem and immature seed of two pigeonpea varieties, Asha and UPAS 120. A total of 3,771 genic-SSR loci, excluding homopolymeric and compound repeats, were identified; of which 2,877 PCR primer pairs were designed for marker development. Dinucleotide was the most common repeat motif with a frequency of 60.41%, followed by tri- (34.52%), hexa- (2.62%), tetra- (1.67%) and pentanucleotide (0.76%) repeat motifs. Primers were synthesized and tested for 772 of these loci with repeat lengths of ≥18 bp. Of these, 550 markers were validated for consistent amplification in eight diverse pigeonpea varieties; 71 were found to be polymorphic on agarose gel electrophoresis. Genetic diversity analysis was done on 22 pigeonpea varieties and eight wild species using 20 highly polymorphic genic-SSR markers. The number of alleles at these loci ranged from 4-10 and the polymorphism information content values ranged from 0.46 to 0.72. Neighbor-joining dendrogram showed distinct separation of the different groups of pigeonpea cultivars and wild species. Deep transcriptome sequencing of the two parental lines helped in silico identification of polymorphic genic-SSR loci to facilitate the rapid development of an intra-species reference genetic map, a subset of which was validated for expected allelic segregation in the reference mapping population. Conclusion We developed 550 validated genic-SSR

SSR: What's in "School Science Review" for "PSR" Readers?

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Lakin, Liz

2004-01-01

This article summarises ideas and developments in teaching and learning in science of relevance to "Primary Science Review" ("PSR") readers from three recent issues (309, 310, and 311) of "School Science Review" ("SSR"), the ASE journal for science education 11-19. The themes running through these are: ICT, the implications for science education…

Optimization of the Geometric Beta for the SSR2 Cavities of the Project X

International Nuclear Information System (INIS)

Solyak, N.; Vostrikov, A.; Yakovlev, V.P.; Awida, M.H.; Berrutti, P.; Gonin, I.V.

2012-01-01

Project X based on the 3 GeV CW superconducting Linac and is currently in the R and D phase. The CW SC Linac starts from a low-energy SCRF section (2.1 - 165 MeV) containing three different types of resonators. HWR f = 162.5 MHz (2.1 - 11 MeV) having beta= 0.11, SSR1 f = 325 MHz (11 - 35 MeV) having beta = 0.21. In this paper we present the analysis that lead to the final design of SSR2 f = 325 MHz cavity (35 - 165 MeV). We present the results of optimization of the geometric beta and the comparison between single, double and triple spoke resonators used in Project X frontend. A β optimization has been carried out for the last spoke cavity section of Project X front end. The optimization process of β opt for a single spoke resonator family SSR2 shown that β opt = 0.47 looks better than the previous choice, which is β opt = 0.4. This change can save some cavities and provide the same final energy for this section, 160 MeV. Single double and triple spoke resonator performances have been compared. The best option is the single spoke resonator SSR2 because the NTTF of a multi-spoke resonator is much narrower than a single one. In the energy range considered (40-160 MeV) the most efficient resonator is the single spoke one.

Genetic diversity and population structure of Brassica oleracea germplasm in Ireland using SSR markers.

Science.gov (United States)

El-Esawi, Mohamed A; Germaine, Kieran; Bourke, Paula; Malone, Renee

2016-01-01

The most economically important Brassica oleracea species is endangered in Ireland, with no prior reported genetic characterization studies. This study assesses the genetic diversity, population structure and relationships of B. oleracea germplasm in Ireland using microsatellite (SSRs) markers. A total of 118 individuals from 25 accessions of Irish B. oleracea were genotyped. The SSR loci used revealed a total of 47 alleles. The observed heterozygosity (0.699) was higher than the expected one (0.417). Moreover, the average values of fixation indices (F) were negative, indicating excess of heterozygotes in all accessions. Polymorphic information content (PIC) values of SSR loci ranged from 0.27 to 0.66, with an average of 0.571, and classified 10 loci as informative markers (PIC>0.5) to differentiate among the accessions studied. The genetic differentiation among accessions showed that 27.1% of the total genetic variation was found among accessions, and 72.9% of the variation resided within accessions. The averages of total heterozygosity (H(T)) and intra-accession genetic diversity (H(S)) were 0.577 and 0.442, respectively. Cluster analysis of SSR data distinguished among kale and Brussels sprouts cultivars. This study provided a new insight into the exploitation of the genetically diverse spring cabbages accessions, revealing a high genetic variation, as potential resources for future breeding programs. SSR loci were effective for differentiation among the accessions studied. Copyright © 2016 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Association of SSR markers with contents of fatty acids in olive oil and genetic diversity analysis of an olive core collection.

Science.gov (United States)

Ipek, M; Ipek, A; Seker, M; Gul, M K

2015-03-27

The purpose of this research was to characterize an olive core collection using some agronomic characters and simple sequence repeat (SSR) markers and to determine SSR markers associated with the content of fatty acids in olive oil. SSR marker analysis demonstrated the presence of a high amount of genetic variation between the olive cultivars analyzed. A UPGMA dendrogram demonstrated that olive cultivars did not cluster on the basis of their geographic origin. Fatty acid components of olive oil in these cultivars were determined. The results also showed that there was a great amount of variation between the olive cultivars in terms of fatty acid composition. For example, oleic acid content ranged from 57.76 to 76.9% with standard deviation of 5.10%. Significant correlations between fatty acids of olive oil were observed. For instance, a very high negative correlation (-0.812) between oleic and linoleic acids was detected. A structured association analysis between the content of fatty acids in olive oil and SSR markers was performed. STRUCTURE analysis assigned olive cultivars to two gene pools (K = 2). Assignment of olive cultivars to these gene pools was not based on geographical origin. Association between fatty acid traits and SSR markers was evaluated using the general linear model of TASSEL. Significant associations were determined between five SSR markers and stearic, oleic, linoleic, and linolenic acids of olive oil. Very high associations (P < 0.001) between ssrOeUA-DCA14 and stearic acid and between GAPU71B and oleic acid indicated that these markers could be used for marker-assisted selection in olive.

Development of SSR markers for a Tibetan medicinal plant, Lancea tibetica (Phrymaceae), based on RAD sequencing.

Science.gov (United States)

Tian, Zunzhe; Zhang, Faqi; Liu, Hairui; Gao, Qingbo; Chen, Shilong

2016-11-01

Lancea tibetica (Phrymaceae), a Tibetan medicinal plant, is endemic to the Qinghai-Tibet Plateau. The over-exploitation of wild L. tibetica has led to the destruction of many populations. To enhance protection and management, biological research, especially population genetic studies, should be carried out on L. tibetica . Simple sequence repeat (SSR) markers of L. tibetica were developed to analyze population diversity. Four thousand four hundred and forty-one SSR loci were identified for L. tibetica based on restriction-site associated DNA (RAD) sequencing on the Illumina HiSeq platform. One hundred SSR loci were arbitrarily selected for primer design, and 38 of them were successfully amplified. These markers were tested on 56 individuals from three populations of L. tibetica , and 10 markers displayed polymorphisms. The total number of alleles per locus ranged from three to eight, and observed and expected heterozygosities ranged from 0.200 to 1.000 and 0.683 to 0.879, respectively. We tested for cross-amplification of these 10 markers in the related species L. hirsuta and found that nine could be successfully amplified. The SSR markers characterized here are the first to be developed and tested in L. tibetica . They will be useful for future population genetic studies on L. tibetica and closely related species.

A genetic linkage map of hexaploid naked oat constructed with SSR markers

Directory of Open Access Journals (Sweden)

Gaoyuan Song

2015-08-01

Full Text Available Naked oat is a unique health food crop in China. Using 202 F2 individuals derived from a hybrid between the variety 578 and the landrace Sanfensan, we constructed a genetic linkage map consisting of 22 linkage groups covering 2070.50 cM and including 208 simple sequence repeat (SSR markers. The minimum distance between adjacent markers was 0.01 cM and the average was 9.95 cM. Each linkage group contained 2–22 markers. The largest linkage group covered 174.40 cM and the shortest one covered 36.80 cM, with an average of 94.11 cM. Thirty-six markers (17.3% showing distorted segregation were distributed across linkage groups LG5 to LG22. This map complements published oat genetic maps and is applicable for quantitative trait locus analysis, gene cloning and molecular marker-assisted selection.

SSR marker based DNA fingerprinting and diversity study in rice ...

African Journals Online (AJOL)

The genetic diversity and DNA fingerprinting of 15 elite rice genotypes using 30 SSR primers on chromosome numbers 7-12 was investigated. The results revealed that all the primers showed distinct polymorphism among the cultivars studied indicating the robust nature of microsatellites in revealing polymorphism. Cluster ...

A Fast Silver Staining Protocol Enabling Simple and Efficient Detection of SSR Markers using a Non-denaturing Polyacrylamide Gel.

Science.gov (United States)

Huang, Ling; Deng, Xiaohui; Li, Ronghua; Xia, Yanshi; Bai, Guihua; Siddique, Kadambot H M; Guo, Peiguo

2018-04-20

Simple Sequence Repeat (SSR) is one of the most effective markers used in plant and animal genetic research and molecular breeding programs. Silver staining is a widely used method for the detection of SSR markers in a polyacrylamide gel. However, conventional protocols for silver staining are technically demanding and time-consuming. Like many other biological laboratory techniques, silver staining protocols have been steadily optimized to improve detection efficiency. Here, we report a simplified silver staining method that significantly reduces reagent costs and enhances the detection resolution and picture clarity. The new method requires two major steps (impregnation and development) and three reagents (silver nitrate, sodium hydroxide, and formaldehyde), and only 7 min of processing for a non-denaturing polyacrylamide gel. Compared to previously reported protocols, this new method is easier, quicker and uses fewer chemical reagents for SSR detection. Therefore, this simple, low-cost, and effective silver staining protocol will benefit genetic mapping and marker-assisted breeding by a quick generation of SSR marker data.

Cranberry SSR multiplexing panels for DNA horticultural fingerprinting and genetic studies

Science.gov (United States)

Cranberry (Vaccinium macrocarpon) is in need of inexpensive high-throughput DNA fingerprinting methods for genetic research and germplasm purity testing for agricultural purposes. Therefore, we designed and validated 16-multiplexing panels containing 61 evenly distributed simple sequence (SSR) marke...

Characterization of expressed sequence tag-derived simple sequence repeat markers for Aspergillus flavus: emphasis on variability of isolates from the southern United States.

Science.gov (United States)

Wang, Xinwang; Wadl, Phillip A; Wood-Jones, Alicia; Windham, Gary; Trigiano, Robert N; Scruggs, Mary; Pilgrim, Candace; Baird, Richard

2012-12-01

Simple sequence repeat (SSR) markers were developed from Aspergillus flavus expressed sequence tag (EST) database to conduct an analysis of genetic relationships of Aspergillus isolates from numerous host species and geographical regions, but primarily from the United States. Twenty-nine primers were designed from 362 tri-nucleotide EST-SSR sequences. Eighteen polymorphic loci were used to genotype 96 Aspergillus species isolates. The number of alleles detected per locus ranged from 2 to 24 with a mean of 8.2 alleles. Haploid diversity ranged from 0.28 to 0.91. Genetic distance matrix was used to perform principal coordinates analysis (PCA) and to generate dendrograms using unweighted pair group method with arithmetic mean (UPGMA). Two principal coordinates explained more than 75 % of the total variation among the isolates. One clade was identified for A. flavus isolates (n = 87) with the other Aspergillus species (n = 7) using PCA, but five distinct clusters were present when the others taxa were excluded from the analysis. Six groups were noted when the EST-SSR data were compared using UPGMA. However, the latter PCA or UPGMA comparison resulted in no direct associations with host species, geographical region or aflatoxin production. Furthermore, there was no direct correlation to visible morphological features such as sclerotial types. The isolates from Mississippi Delta region, which contained the largest percentage of isolates, did not show any unusual clustering except for isolates K32, K55, and 199. Further studies of these three isolates are warranted to evaluate their pathogenicity, aflatoxin production potential, additional gene sequences (e.g., RPB2), and morphological comparisons.

A set of tetra-nucleotide core motif SSR markers for efficient identification of potato (Solanum tuberosum) cultivars.

Science.gov (United States)

Kishine, Masahiro; Tsutsumi, Katsuji; Kitta, Kazumi

2017-12-01

Simple sequence repeat (SSR) is a popular tool for individual fingerprinting. The long-core motif (e.g. tetra-, penta-, and hexa-nucleotide) simple sequence repeats (SSRs) are preferred because they make it easier to separate and distinguish neighbor alleles. In the present study, a new set of 8 tetra-nucleotide SSRs in potato ( Solanum tuberosum ) is reported. By using these 8 markers, 72 out of 76 cultivars obtained from Japan and the United States were clearly discriminated, while two pairs, both of which arose from natural variation, showed identical profiles. The combined probability of identity between two random cultivars for the set of 8 SSR markers was estimated to be 1.10 × 10 -8 , confirming the usefulness of the proposed SSR markers for fingerprinting analyses of potato.

Single nucleotide polymorphism isolated from a novel EST dataset in garden asparagus (Asparagus officinalis L.).

Science.gov (United States)

Mercati, Francesco; Riccardi, Paolo; Leebens-Mack, Jim; Abenavoli, Maria Rosa; Falavigna, Agostino; Sunseri, Francesco

2013-04-01

Single nucleotide polymorphisms (SNPs) and simple sequence repeats (SSR) are abundant and evenly distributed co-dominant molecular markers in plant genomes. SSRs are valuable for marker assisted breeding and positional cloning of genes associated traits of interest. Although several high throughput platforms have been developed to identify SNP and SSR markers for analysis of segregant plant populations, breeding in garden asparagus (Asparagus officinalis L.) has been limited by a low content of such markers. In this study massively parallel GS-FLX pyro-sequencing technology (454 Life Sciences) has been used to sequence and compare transcriptome from two genotypes: a rust tolerant male (1770) and a susceptible female (G190). A total of 122,963 and 99,368 sequence reads, with an average length of 245.7bp, have been recovered from accessions 1770 and 190 respectively. A computational pipeline has been used to predict and visually inspect putative SNPs and SSR sequences. Analysis of Gene Ontology (GO) slim annotation assignments for all assembled uniscripts indicated that the 24,403 assemblies represent genes from a broad array of functions. Further, over 1800 putative SNPs and 1000 SSRs were detected. One hundred forty-four SNPs together with 60 selected SSRs were validated and used to develop a preliminary genetic map by using a large BC(1) population, derived from 1770 and G190. The abundance of SNPs and SSRs provides a foundation for the development of saturated genetic maps and their utilization in assisted asparagus breeding programs. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Genetic variation of european maize genotypes (zea mays l. Detected using ssr markers

Directory of Open Access Journals (Sweden)

Martin Vivodík

2017-01-01

Full Text Available The SSR molecular markers were used to assess genetic diversity in 40 old European maize genotypes. Ten SSR primers revealed a total of 65 alleles ranging from 4 (UMC1060 to 8 (UMC2002 and UMC1155 alleles per locus with a mean value of 6.50 alleles per locus. The PIC values ranged from 0.713 (UMC1060 to 0.842 (UMC2002 with an average value of 0.810 and the DI value ranged from 0.734 (UMC1060 to 0.848 (UMC2002 with an average value of 0.819. 100% of used SSR markers had PIC and DI values higher than 0.7 that means high polymorphism of chosen markers used for analysis. Probability of identity (PI was low ranged from 0.004 (UMC1072 to 0.022 (UMC1060 with an average of 0.008. A dendrogram was constructed from a genetic distance matrix based on profiles of the 10 maize SSR loci using the unweighted pair-group method with the arithmetic average (UPGMA. According to analysis, the collection of 40 diverse accessions of maize was clustered into four clusters. The first cluster contained nine genotypes of maize, while the second cluster contained the four genotypes of maize. The third cluster contained 5 maize genotypes. Cluster 4 contained five genotypes from Hungary (22.73%, two genotypes from Poland (9.10%, seven genotypes of maize from Union of Soviet Socialist Republics (31.81%, six genotypes from Czechoslovakia (27.27%, one genotype from Slovak Republic (4.55% and one genotype of maize is from Yugoslavia (4.55%. We could not distinguish 4 maize genotypes grouped in cluster 4, (Voroneskaja and Kocovska Skora and 2 Hungarian maize genotypes - Feheres Sarga Filleres and Mindszentpusztai Feher, which are genetically the closest.

Leaf Transcriptome Sequencing for Identifying Genic-SSR Markers and SNP Heterozygosity in Crossbred Mango Variety 'Amrapali' (Mangifera indica L.).

Science.gov (United States)

Mahato, Ajay Kumar; Sharma, Nimisha; Singh, Akshay; Srivastav, Manish; Jaiprakash; Singh, Sanjay Kumar; Singh, Anand Kumar; Sharma, Tilak Raj; Singh, Nagendra Kumar

2016-01-01

Mango (Mangifera indica L.) is called "king of fruits" due to its sweetness, richness of taste, diversity, large production volume and a variety of end usage. Despite its huge economic importance genomic resources in mango are scarce and genetics of useful horticultural traits are poorly understood. Here we generated deep coverage leaf RNA sequence data for mango parental varieties 'Neelam', 'Dashehari' and their hybrid 'Amrapali' using next generation sequencing technologies. De-novo sequence assembly generated 27,528, 20,771 and 35,182 transcripts for the three genotypes, respectively. The transcripts were further assembled into a non-redundant set of 70,057 unigenes that were used for SSR and SNP identification and annotation. Total 5,465 SSR loci were identified in 4,912 unigenes with 288 type I SSR (n ≥ 20 bp). One hundred type I SSR markers were randomly selected of which 43 yielded PCR amplicons of expected size in the first round of validation and were designated as validated genic-SSR markers. Further, 22,306 SNPs were identified by aligning high quality sequence reads of the three mango varieties to the reference unigene set, revealing significantly enhanced SNP heterozygosity in the hybrid Amrapali. The present study on leaf RNA sequencing of mango varieties and their hybrid provides useful genomic resource for genetic improvement of mango.

Fingerprinting and genetic purity assessment of F1 barley hybrids and their salt-tolerant parental lines using nSSR molecular markers.

Science.gov (United States)

Ben Romdhane, Mériam; Riahi, Leila; Jardak, Rahma; Ghorbel, Abdelwahed; Zoghlami, Nejia

2018-01-01

Hybridity and the genuineness of hybrids are prominent characteristics for quality control of seeds and thereby for varietal improvement. In the current study, the cross between two local barley genotypes (Ardhaoui: female; Testour: male) previously identified as susceptible/tolerant to salt stress in Tunisia was achieved. The hybrid genetic purity of the generated F 1 putative hybrids and the fingerprinting of the parents along with their offspring were assessed using a set of 17 nuclear SSR markers. Among the analyzed loci, 11 nSSR were shown polymorphic among the parents and their offspring. Based on the applied 11 polymorphic SSR loci, a total of 28 alleles were detected with an average of 2.54 alleles per locus. The locus HVM33 presented the highest number of alleles. The highest polymorphism information content value was detected for the locus HVM33 (0.6713) whereas the lowest PIC value (0.368) was revealed by the loci BMAC0156 , EBMAC0970 and BMAG0013 with a mean value of 0.4619. The probabilities of identical genotypes PI for the 11 microsatellite markers were 8.63 × 10 -7 . Banding patterns among parents and hybrids showed polymorphic fragments. The 11 SSR loci had produced unique fingerprints for each analyzed genotype and segregate between the two parental lines and their four hybrids. Parentage analysis confirms the hybrid purity of the four analyzed genotypes. Six Tunisian barley accessions were used as an outgroup in the multivariate analysis to confirm the efficiency of the employed 11 nSSR markers in genetic differentiation among various barley germplasms. Thus, neighbor joining and factorial analysis revealed clearly the discrimination among the parental lines, the four hybrids and the outgroup accessions. Out of the detected polymorphic 11 nuclear SSR markers, a set of five markers ( HVM33 , WMC1E8 , BMAC0154 , BMAC0040 and BMAG0007 ) were shown to be sufficient and informative enough to discriminate among the six genotypes representing the two

Database derived microsatellite markers (SSRs) for cultivar differentiation in Brassica oleracea

DEFF Research Database (Denmark)

Louarn, Sébastien Jean Yves; Torp, Anna Maria; Holme, I.B.

2007-01-01

 Fifty-nine Brassica oleracea cultivars, belonging to five botanical varieties, were evaluated for microsatellite (SSR) polymorphisms using 11 database sequence derived primer pairs. The cultivars represented 12 broccoli (Brassica oleracea var. italica), ten Brussels sprouts (B. o. var. gemmifera...

Identification of SSR and RAPD markers associated with QTLs of ...

African Journals Online (AJOL)

SERVER

2008-04-03

Apr 3, 2008 ... Parents and. F3 families had significant differences in studied traits (p ≤. 0.01). In this study, SSR and RAPD markers were used together for constructing linkage groups and rescanning the genome of rapeseed to identify QTLs controlling winter survival and related traits. For this, the parental polymorphism ...

Genome-Wide Development of MicroRNA-Based SSR Markers in Medicago truncatula with Their Transferability Analysis and Utilization in Related Legume Species.

Science.gov (United States)

Min, Xueyang; Zhang, Zhengshe; Liu, Yisong; Wei, Xingyi; Liu, Zhipeng; Wang, Yanrong; Liu, Wenxian

2017-11-18

Microsatellite (simple sequence repeats, SSRs) marker is one of the most widely used markers in marker-assisted breeding. As one type of functional markers, MicroRNA-based SSR (miRNA-SSR) markers have been exploited mainly in animals, but the development and characterization of miRNA-SSR markers in plants are still limited. In the present study, miRNA-SSR markers for Medicago truncatula ( M. truncatula ) were developed and their cross-species transferability in six leguminous species was evaluated. A total of 169 primer pairs were successfully designed from 130 M. truncatula miRNA genes, the majority of which were mononucleotide repeats (70.41%), followed by dinucleotide repeats (14.20%), compound repeats (11.24%) and trinucleotide repeats (4.14%). Functional classification of SSR-containing miRNA genes showed that all targets could be grouped into three Gene Ontology (GO) categories: 17 in biological process, 11 in molecular function, and 14 in cellular component. The miRNA-SSR markers showed high transferability in other six leguminous species, ranged from 74.56% to 90.53%. Furthermore, 25 Mt - miRNA-SSR markers were used to evaluate polymorphisms in 20 alfalfa accessions, and the polymorphism information content (PIC) values ranged from 0.39 to 0.89 with an average of 0.71, the allele number per marker varied from 3 to 18 with an average of 7.88, indicating a high level of informativeness. The present study is the first time developed and characterized of M. truncatula miRNA-SSRs and demonstrated their utility in transferability, these novel markers will be valuable for genetic diversity analysis, marker-assisted selection and genotyping in leguminous species.

New gSSR and EST-SSR markers reveal high genetic diversity in the invasive plant Ambrosia artemisiifolia L. and can be transferred to other invasive Ambrosia species.

Science.gov (United States)

Meyer, Lucie; Causse, Romain; Pernin, Fanny; Scalone, Romain; Bailly, Géraldine; Chauvel, Bruno; Délye, Christophe; Le Corre, Valérie

2017-01-01

Ambrosia artemisiifolia L., (common ragweed), is an annual invasive and highly troublesome plant species originating from North America that has become widespread across Europe. New sets of genomic and expressed sequence tag (EST) based simple sequence repeats (SSRs) markers were developed in this species using three approaches. After validation, 13 genomic SSRs and 13 EST-SSRs were retained and used to characterize the genetic diversity and population genetic structure of Ambrosia artemisiifolia populations from the native (North America) and invasive (Europe) ranges of the species. Analysing the mating system based on maternal families did not reveal any departure from complete allogamy and excess homozygosity was mostly due the presence of null alleles. High genetic diversity and patterns of genetic structure in Europe suggest two main introduction events followed by secondary colonization events. Cross-species transferability of the newly developed markers to other invasive species of the Ambrosia genus was assessed. Sixty-five percent and 75% of markers, respectively, were transferable from A. artemisiifolia to Ambrosia psilostachya and Ambrosia tenuifolia. 40% were transferable to Ambrosia trifida, this latter species being seemingly more phylogenetically distantly related to A. artemisiifolia than the former two.

Alleviation SSR and Low Frequency Power Oscillations in Series Compensated Transmission Line using SVC Supplementary Controllers

Science.gov (United States)

Kumar, Sanjiv; Kumar, Narendra

2017-06-01

In this work, supplementary sub-synchronous damping controllers (SSDC) are proposed for damping sub-synchronous oscillations in power systems with series compensated transmission lines. Series compensation have extensively been used as effective means of increasing the power transfer capability of a transmission lines and improving transient stability limits of power systems. Series compensation with transmission lines may cause sub-synchronous resonance (SSR). The eigenvalue investigation tool is used to ascertain the existence of SSR. It is shown that the addition of supplementary controller is able to stabilize all unstable modes for T-network model. Eigenvalue investigation and time domain transient simulation of detailed nonlinear system are considered to investigate the performance of the controllers. The efficacies of the suggested supplementary controllers are compared on the IEEE first benchmark model for computer simulations of SSR by means of time domain simulation in Matlab/Simulink environment. Supplementary SSDC are considered in order to compare effectiveness of SSDC during higher loading in alleviating the small signal stability problem.

4-(2-Chloro-4-methoxy-5-methylphenyl)-N-[(1S)-2-cyclopropyl-1-(3-fluoro-4-methylphenyl)ethyl]5-methyl-N-(2-propynyl)-1,3-thiazol-2-amine hydrochloride (SSR125543A): a potent and selective corticotrophin-releasing factor(1) receptor antagonist. I. Biochemical and pharmacological characterization.

Science.gov (United States)

Gully, Danielle; Geslin, Michel; Serva, Laurence; Fontaine, Evelyne; Roger, Pierre; Lair, Christine; Darre, Valerie; Marcy, Claudine; Rouby, Pierre-Eric; Simiand, Jacques; Guitard, Josette; Gout, Georgette; Steinberg, Regis; Rodier, Daniel; Griebel, Guy; Soubrie, Philippe; Pascal, Marc; Pruss, Rebecca; Scatton, Bernard; Maffrand, Jean-Pierre; Le Fur, Gerard

2002-04-01

4-(2-Chloro-4-methoxy-5-methylphenyl)-N-[(1S)-2-cyclopropyl-1- (3-fluoro-4-methylphenyl)ethyl]5-methyl-N-(2-propynyl)-1,3-thiazol-2-amine hydrochloride (SSR125543A), a new 2-aminothiazole derivative, shows nanomolar affinity for human cloned or native corticotrophin-releasing factor (CRF)(1) receptors (pK(i) values of 8.73 and 9.08, respectively), and a 1000-fold selectivity for CRF(1) versus CRF(2 alpha) receptor and CRF binding protein. SSR125543A antagonizes CRF-induced stimulation of cAMP synthesis in human retinoblastoma Y 79 cells (IC(50) = 3.0 +/- 0.4 nM) and adrenocorticotropin hormone (ACTH) secretion in mouse pituitary tumor AtT-20 cells. SSR125543A is devoid of agonist activity in these models. Its brain penetration was demonstrated in rats by using an ex vivo [(125)I-Tyr(0)] ovine CRF binding assay. SSR125543A displaced radioligand binding to the CRF(1) receptor in the brain with an ID(50) of 6.5 mg/kg p.o. (duration of action >24 h). SSR125543A also inhibited the increase in plasma ACTH levels elicited in rats by i.v. CRF (4 microg/kg) injection (ID(50) = 1, 5, or 5 mg/kg i.v., i.p., and p.o., respectively); this effect lasted for more than 6 h when the drug was given orally at a dose of 30 mg/kg. SSR125543A (10 mg/kg p.o.) reduced by 73% the increase in plasma ACTH levels elicited by a 15-min restraint stress in rats. Moreover, SSR125543A (20 mg/kg i.p.) also antagonized the increase of hippocampal acetylcholine release induced by i.c.v. injection of 1 microg of CRF in rats. Finally, SSR125543A reduced forepaw treading induced by i.c.v. injection of 1 microg of CRF in gerbils (ID(50) = approximately 10 mg/kg p.o.). Altogether, these data indicate that SSR125543A is a potent, selective, and orally active CRF(1) receptor antagonist.

Factors Affecting SSR in Holstein Dairy Cows

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Alireza Heravi Mosavi

2016-08-01

Full Text Available Introduction Secondary sex ratio (SSR is the proportion of males to females at birth. It has been shown in many different mammalian species, many factors are associated with SSR. Changes in secondary sex ratio in dairy cows is considered economically important and the ability to change it could affect the revenues and profitability of a dairy farm. Thus, sperm or embryo sexing techniques in recent years has attracted more attention. Most breed of dairy cattle are more likely to have female calf is born to use them as replacement heifers and in order to maintain their productive herd number. On the contrary, when the goal is the production of meat, bull calves due to higher growth rates and production efficiency, are more convenient and more economically efficient. The aim of present study was to investigate some key factors affecting SSR in Iranian Holstein cows. According to Fisher, the sex ratio in the population under the control of natural selection is not always the same. There is overwhelming evidence to support the theory that shows Fisher Primary and secondary sex ratio sex ratio can deviate from this balance and natural selection caused a change in this ratio can be in certain circumstances. For example, the secondary sex ratio of 52:48 has been reported in dairy cows. Studies on mammalian species suggest that several factors, including latitude of the location, the dominant regional climate model, time and frequency of mating to ovulation, diet, age of parents, physical score, breed and produced eggs from ovarian left or right can have a significant effect on the secondary sex ratio. Weather conditions may modify the internal environment and the effect on physiological mechanisms or through the impact on the frequency and type of foods available to parents, the secondary sex ratio is impressive. The impact on the quantity and quality of parent's access to food sources in many species of mammals, the sex ratio has been fixed. Previous

Identification and differentiation of Ricinus communis L. using SSR markers

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Zdenka Gálová

2015-12-01

Full Text Available Normal 0 false false false CS JA X-NONE The castor-oil plant (Ricinus communis L., a member of the spurge family (Euphorbiaceae, is a versatile industrial oil crop that is cultivated in many tropical and subtropical regions of the world. Castor oil is of continuing importance to the global specialty chemical industry because it is the only commercial source of a hydroxylated fatty acid. Castor also has tremendous future potential as an industrial oilseed crop because of its high seed oil content, unique fatty acid composition, potentially high oil yields and ability to be grown under drought and saline conditions. Knowledge of genetic variability is important for breeding programs to provide the basis for developing desirable genotypes. The aim of this study was to assess genetic diversity within the set of 60 ricin genotypes using 10 SSR primers. Ten SSR primers revealed a total of 67 alleles ranging from 4 to 9 alleles per locus with a mean value of 6.70 alleles per locus. The PIC values ranged from 0.719 to 0.860 with an average value of 0.813 and the DI value ranged from 0.745 to 0.862 with an average value of 0.821. Probability of identity (PI was low ranged from 0.004 to 0.018 with an average of 0.008. A dendrogram was constructed from a genetic distance matrix based on profiles of the 10 SSR loci using the unweighted pair-group method with the arithmetic average (UPGMA. According to analysis, the collection of 60 diverse accessions of castor bean was clustered into six clusters. We could not distinguish 2 genotypes grouped in cluster 1, RM-96 and RM-98, which are genetically the closest. Knowledge on the genetic diversity of castor can be used to future breeding programs of castor.

Molecular genetic alterations in egfr CA-SSR-1 microsatellite and egfr copy number changes are associated with aggressiveness in thymoma.

Science.gov (United States)

Conti, Salvatore; Gallo, Enzo; Sioletic, Stefano; Facciolo, Francesco; Palmieri, Giovannella; Lauriola, Libero; Evoli, Amelia; Martucci, Robert; Di Benedetto, Anna; Novelli, Flavia; Giannarelli, Diana; Deriu, Gloria; Granone, Pierluigi; Ottaviano, Margaret; Muti, Paola; Pescarmona, Edoardo; Marino, Mirella

2016-03-01

The key role of egfr in thymoma pathogenesis has been questioned following the failure in identifying recurrent genetic alterations of egfr coding sequences and relevant egfr amplification rate. We investigated the role of the non-coding egfr CA simple sequence repeat 1 (CA-SSR-1) in a thymoma case series. We used sequencing and egfr-fluorescence in situ hybridization (FISH) to genotype 43 thymomas; (I) for polymorphisms and somatic loss of heterozygosity of the non-coding egfr CA-SSR-1 microsatellite and (II) for egfr gene copy number changes. We found two prevalent CA-SSR-1 genotypes: a homozygous 16 CA repeat and a heterozygous genotype, bearing alleles with 16 and 20 CA repeats. The average combined allele length was correlated with tumor subtype: shorter sequences were significantly associated with the more aggressive WHO thymoma subtype group including B2/B3, B3 and B3/C histotypes. Four out of 29 informative cases analysed for somatic CA-SSR-1 loss of heterozygosity showed allelic imbalance (AI), 3/4 with loss of the longer allele. By egfr-FISH analysis, 9 out of 33 cases were FISH positive. Moreover, the two integrated techniques demonstrated that 3 out of 4 CA-SSR-1-AI positive cases with short allele relative prevalence showed significantly low or high chromosome 7 "polysomy"/increased gene copy number by egfr-FISH. Our molecular and genetic and follow up data indicated that CA-SSR-1-allelic imbalance with short allele relative prevalence significantly correlated with EGFR 3+ immunohistochemical score, increased egfr Gene Copy Number, advanced stage and with relapsing/metastatic behaviour in thymomas.

Development and mapping of SSR markers linked to resistance-gene homologue clusters in common bean

Institute of Scientific and Technical Information of China (English)

Luz; Nayibe; Garzon; Matthew; Wohlgemuth; Blair

2014-01-01

Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistance-gene homologue(RGH) cloning has proven to be an efficient tool for identifying markers and R(resistance) genes associated with resistances to diseases. Microsatellite or SSR markers can be identified by physical association with RGH clones on large-insert DNA clones such as bacterial artificial chromosomes(BACs). Our objectives in this work were to identify RGH-SSR in a BAC library from the Andean genotype G19833 and to test and map any polymorphic markers to identify associations with known positions of disease resistance genes. We developed a set of specific probes designed for clades of common bean RGH genes and then identified positive BAC clones and developed microsatellites from BACs having SSR loci in their end sequences. A total of 629 new RGH-SSRs were identified and named BMr(bean microsatellite RGH-associated markers). A subset of these markers was screened for detecting polymorphism in the genetic mapping population DOR364 × G19833. A genetic map was constructed with a total of 264 markers,among which were 80 RGH loci anchored to single-copy RFLP and SSR markers. Clusters of RGH-SSRs were observed on most of the linkage groups of common bean and in positions associated with R-genes and QTL. The use of these new markers to select for disease resistance is discussed.

Identification of new SSR markers linked to leaf chlorophyll content, flag leaf senescence and cell membrane stability traits in wheat under water stressed condition.

Science.gov (United States)

Barakat, Mohamed N; Saleh, Mohamed; Al-Doss, Abdullah A; Moustafa, Khaled A; Elshafei, Adel A; Al-Qurainy, Fahed H

2015-03-01

Segregating F4 families from the cross between drought sensitive (Yecora Rojo) and drought tolerant (Pavon 76) genotypes were made to identify SSR markers linked to leaf chlorophyll content, flag leaf senescence and cell membrane stability traits in wheat (Triticum aestivum L.) under water-stressed condition and to map quantitative trait locus (QTL) for the three physiological traits. The parents and 150 F4 families were evaluated phenotypically for drought tolerance using two irrigation treatments (2500 and 7500 m3/ha). Using 400 SSR primers tested for polymorphism in testing parental and F4 families genotypes, the results revealed that QTL for leaf chlorophyll content, flag leaf senescence and cell membrane stability traits were associated with 12, 5 and 12 SSR markers, respectively and explained phenotypic variation ranged from 6 to 42%. The SSR markers for physiological traits had genetic distances ranged from 12.5 to 25.5 cM. These SSR markers can be further used in breeding programs for drought tolerance in wheat.

Genome-Wide Analysis of Simple Sequence Repeats and Efficient Development of Polymorphic SSR Markers Based on Whole Genome Re-Sequencing of Multiple Isolates of the Wheat Stripe Rust Fungus.

Directory of Open Access Journals (Sweden)

Huaiyong Luo

Full Text Available The biotrophic parasitic fungus Puccinia striiformis f. sp. tritici (Pst causes stripe rust, a devastating disease of wheat, endangering global food security. Because the Pst population is highly dynamic, it is difficult to develop wheat cultivars with durable and highly effective resistance. Simple sequence repeats (SSRs are widely used as molecular markers in genetic studies to determine population structure in many organisms. However, only a small number of SSR markers have been developed for Pst. In this study, a total of 4,792 SSR loci were identified using the whole genome sequences of six isolates from different regions of the world, with a marker density of one SSR per 22.95 kb. The majority of the SSRs were di- and tri-nucleotide repeats. A database containing 1,113 SSR markers were established. Through in silico comparison, the previously reported SSR markers were found mainly in exons, whereas the SSR markers in the database were mostly in intergenic regions. Furthermore, 105 polymorphic SSR markers were confirmed in silico by their identical positions and nucleotide variations with INDELs identified among the six isolates. When 104 in silico polymorphic SSR markers were used to genotype 21 Pst isolates, 84 produced the target bands, and 82 of them were polymorphic and revealed the genetic relationships among the isolates. The results show that whole genome re-sequencing of multiple isolates provides an ideal resource for developing SSR markers, and the newly developed SSR markers are useful for genetic and population studies of the wheat stripe rust fungus.

Genome-Wide Analysis of Simple Sequence Repeats and Efficient Development of Polymorphic SSR Markers Based on Whole Genome Re-Sequencing of Multiple Isolates of the Wheat Stripe Rust Fungus.

Science.gov (United States)

Luo, Huaiyong; Wang, Xiaojie; Zhan, Gangming; Wei, Guorong; Zhou, Xinli; Zhao, Jing; Huang, Lili; Kang, Zhensheng

2015-01-01

The biotrophic parasitic fungus Puccinia striiformis f. sp. tritici (Pst) causes stripe rust, a devastating disease of wheat, endangering global food security. Because the Pst population is highly dynamic, it is difficult to develop wheat cultivars with durable and highly effective resistance. Simple sequence repeats (SSRs) are widely used as molecular markers in genetic studies to determine population structure in many organisms. However, only a small number of SSR markers have been developed for Pst. In this study, a total of 4,792 SSR loci were identified using the whole genome sequences of six isolates from different regions of the world, with a marker density of one SSR per 22.95 kb. The majority of the SSRs were di- and tri-nucleotide repeats. A database containing 1,113 SSR markers were established. Through in silico comparison, the previously reported SSR markers were found mainly in exons, whereas the SSR markers in the database were mostly in intergenic regions. Furthermore, 105 polymorphic SSR markers were confirmed in silico by their identical positions and nucleotide variations with INDELs identified among the six isolates. When 104 in silico polymorphic SSR markers were used to genotype 21 Pst isolates, 84 produced the target bands, and 82 of them were polymorphic and revealed the genetic relationships among the isolates. The results show that whole genome re-sequencing of multiple isolates provides an ideal resource for developing SSR markers, and the newly developed SSR markers are useful for genetic and population studies of the wheat stripe rust fungus.

Leaf Transcriptome Sequencing for Identifying Genic-SSR Markers and SNP Heterozygosity in Crossbred Mango Variety ‘Amrapali’ (Mangifera indica L.)

Science.gov (United States)

Mahato, Ajay Kumar; Sharma, Nimisha; Singh, Akshay; Srivastav, Manish; Jaiprakash; Singh, Sanjay Kumar; Singh, Anand Kumar; Sharma, Tilak Raj; Singh, Nagendra Kumar

2016-01-01

Mango (Mangifera indica L.) is called “king of fruits” due to its sweetness, richness of taste, diversity, large production volume and a variety of end usage. Despite its huge economic importance genomic resources in mango are scarce and genetics of useful horticultural traits are poorly understood. Here we generated deep coverage leaf RNA sequence data for mango parental varieties ‘Neelam’, ‘Dashehari’ and their hybrid ‘Amrapali’ using next generation sequencing technologies. De-novo sequence assembly generated 27,528, 20,771 and 35,182 transcripts for the three genotypes, respectively. The transcripts were further assembled into a non-redundant set of 70,057 unigenes that were used for SSR and SNP identification and annotation. Total 5,465 SSR loci were identified in 4,912 unigenes with 288 type I SSR (n ≥ 20 bp). One hundred type I SSR markers were randomly selected of which 43 yielded PCR amplicons of expected size in the first round of validation and were designated as validated genic-SSR markers. Further, 22,306 SNPs were identified by aligning high quality sequence reads of the three mango varieties to the reference unigene set, revealing significantly enhanced SNP heterozygosity in the hybrid Amrapali. The present study on leaf RNA sequencing of mango varieties and their hybrid provides useful genomic resource for genetic improvement of mango. PMID:27736892

Identification of SSR markers closely linked to the yellow seed coat color gene in heading Chinese cabbage (Brassica rapa L. ssp. pekinensis).

Science.gov (United States)

Ren, Yanjing; Wu, Junqing; Zhao, Jing; Hao, Lingyu; Zhang, Lugang

2017-02-15

Research on the yellow-seeded variety of heading Chinese cabbage will aid in broadening its germplasm resources and lay a foundation for AA genome research in Brassica crops. Here, an F 2 segregating population of 1575 individuals was constructed from two inbred lines (brown-seeded '92S105' and yellow-seeded '91-125'). This population was used to identify the linkage molecular markers of the yellow seed coat trait using simple sequence repeat (SSR) techniques combined with a bulk segregant analysis (BSA). Of the 144 SSR primer pairs on the A01-A10 chromosomes from the Brassica database (http://brassicadb.org/brad/), two pairs located on the A06 chromosome showed polymorphic bands between the bulk DNA pools of eight brown-seeded and eight yellow-seeded F 2 progeny. Based on the genome sequence, 454 SSR markers were designed to A06 to detect these polymorphic bands and were synthesized. Six SSR markers linked to the seed coat color gene were successfully selected for fine linkage genetic map construction, in which the two closest flanking markers, SSR449a and SSR317, mapped the Brsc-ye gene to a 40.2 kb region with distances of 0.07 and 0.06 cM, respectively. The molecular markers obtained in this report will assist in the marker-assisted selection and breeding of yellow-seeded lines in Brassica rapa L. and other close species. © 2017. Published by The Company of Biologists Ltd.

A high density barley microsatellite consensus map with 775 SSR loci

NARCIS (Netherlands)

Varshney, R.K.; Marcel, T.C.; Ramsay, L.; Russell, J.; Roder, M.S.; Stein, N.; Waugh, R.; Langridge, P.; Niks, R.E.; Graner, A.

2007-01-01

A microsatellite or simple sequence repeat (SSR) consensus map of barley was constructed by joining six independent genetic maps based on the mapping populations 'Igri x Franka', 'Steptoe x Morex', 'OWBRec x OWBDom', 'Lina x Canada Park', 'L94 x Vada' and 'SusPtrit x Vada'. Segregation data for

High levels of heterozygosity found for 15 SSR loci in Solanum chacoense

Science.gov (United States)

Genetic variation is a necessary prerequisite for improving domesticated plants through breeding; without it, breeding progress would be impossible. Genetic variation can be readily ascertained with co-dominant DNA markers, such as simple sequence repeats (SSRs). Twenty-four SSR markers specifically...

Genetic Variation and Association Analysis of the SSR Markers Linked to the Major Drought-Yield QTLs of Rice.

Science.gov (United States)

Tabkhkar, Narjes; Rabiei, Babak; Samizadeh Lahiji, Habibollah; Hosseini Chaleshtori, Maryam

2018-02-24

Drought is one of the major abiotic stresses, which hampers the production of rice worldwide. Informative molecular markers are valuable tools for improving the drought tolerance in various varieties of rice. The present study was conducted to evaluate the informative simple sequence repeat (SSR) markers in a diverse set of rice genotypes. The genetic diversity analyses of the 83 studied rice genotypes were performed using 34 SSR markers closely linked to the major quantitative trait loci (QTLs) of grain yield under drought stress (qDTYs). In general, our results indicated high levels of polymorphism. In addition, we screened these rice genotypes at the reproductive stage under both drought stress and nonstressful conditions. The results of the regression analysis demonstrated a significant relationship between 11 SSR marker alleles and the plant paddy weight under stressful conditions. Under the nonstressful conditions, 16 SSR marker alleles showed a significant correlation with the plant paddy weight. Finally, four markers (RM279, RM231, RM166, and RM231) demonstrated a significant association with the plant paddy weight under both stressful and nonstressful conditions. These informative-associated alleles may be useful for improving the crop yield under both drought stress and nonstressful conditions in breeding programs.

Localized infusions of the partial alpha 7 nicotinic receptor agonist SSR180711 evoke rapid and transient increases in prefrontal glutamate release

DEFF Research Database (Denmark)

Bortz, D M; Mikkelsen, J D; Bruno, J P

2013-01-01

The ability of local infusions of the alpha 7 nicotinic acetycholine receptor (α7 nAChR) partial agonist SSR180711 to evoke glutamate release in prefrontal cortex was determined in awake rats using a microelectrode array. Infusions of SSR180711 produced dose-dependent increases in glutamate levels...

Genetic diversity based on SSR markers in maize (Zea mays L.)

Indian Academy of Sciences (India)

Home; Journals; Journal of Genetics; Volume 87; Issue 3. Genetic diversity based on SSR markers in maize (Zea mays L.) landraces from Wuling mountain region in China. Yao Qi-Lun Fang Ping Kang Ke-Cheng Pan Guang-Tang. Research Note Volume 87 Issue 3 December 2008 pp 287-291 ...

Genetic diversity in watermelon (Citrullus lanatus) landraces from Zimbabwe revealed by RAPD and SSR markers.

Science.gov (United States)

Mujaju, C; Sehic, J; Werlemark, G; Garkava-Gustavsson, L; Fatih, M; Nybom, H

2010-08-01

Low polymorphism in cultivated watermelon has been reported in previous studies, based mainly on US Plant Introductions and watermelon cultivars, most of which were linked to breeding programmes associated with disease resistance. Since germplasm sampled in a putative centre of origin in southern Africa may harbour considerably higher variability, DNA marker-based diversity was estimated among 81 seedlings from eight accessions of watermelon collected in Zimbabwe; five accessions of cow-melons (Citrullus lanatus var. citroides) and three of sweet watermelons (C. lanatus var. lanatus). Two molecular marker methods were used, random amplified polymorphic DNA (RAPD) and simple sequence repeats (SSR) also known as microsatellite DNA. Ten RAPD primers produced 138 markers of which 122 were polymorphic. Nine SSR primer pairs detected a total of 43 alleles with an average of 4.8 alleles per locus. The polymorphic information content (PIC) ranged from 0.47 to 0.77 for the RAPD primers and from 0.39 to 0.97 for the SSR loci. Similarity matrices obtained with SSR and RAPD, respectively, were highly correlated but only RAPD was able to provide each sample with an individual-specific DNA profile. Dendrograms and multidimensional scaling (MDS) produced two major clusters; one with the five cow-melon accessions and the other with the three sweet watermelon accessions. One of the most variable cow-melon accessions took an intermediate position in the MDS analysis, indicating the occurrence of gene flow between the two subspecies. Analysis of molecular variation (AMOVA) attributed most of the variability to within-accessions, and contrary to previous reports, sweet watermelon accessions apparently contain diversity of the same magnitude as the cow-melons.

A first linkage map and downy mildew resistance QTL discovery for sweet basil (Ocimum basilicum) facilitated by double digestion restriction site associated DNA sequencing (ddRADseq).

Science.gov (United States)

Pyne, Robert; Honig, Josh; Vaiciunas, Jennifer; Koroch, Adolfina; Wyenandt, Christian; Bonos, Stacy; Simon, James

2017-01-01

Limited understanding of sweet basil (Ocimum basilicum L.) genetics and genome structure has reduced efficiency of breeding strategies. This is evidenced by the rapid, worldwide dissemination of basil downy mildew (Peronospora belbahrii) in the absence of resistant cultivars. In an effort to improve available genetic resources, expressed sequence tag simple sequence repeat (EST-SSR) and single nucleotide polymorphism (SNP) markers were developed and used to genotype the MRI x SB22 F2 mapping population, which segregates for response to downy mildew. SNP markers were generated from genomic sequences derived from double digestion restriction site associated DNA sequencing (ddRADseq). Disomic segregation was observed in both SNP and EST-SSR markers providing evidence of an O. basilicum allotetraploid genome structure and allowing for subsequent analysis of the mapping population as a diploid intercross. A dense linkage map was constructed using 42 EST-SSR and 1,847 SNP markers spanning 3,030.9 cM. Multiple quantitative trait loci (QTL) model (MQM) analysis identified three QTL that explained 37-55% of phenotypic variance associated with downy mildew response across three environments. A single major QTL, dm11.1 explained 21-28% of phenotypic variance and demonstrated dominant gene action. Two minor QTL dm9.1 and dm14.1 explained 5-16% and 4-18% of phenotypic variance, respectively. Evidence is provided for an additive effect between the two minor QTL and the major QTL dm11.1 increasing downy mildew susceptibility. Results indicate that ddRADseq-facilitated SNP and SSR marker genotyping is an effective approach for mapping the sweet basil genome.

Microsatellites for the genus Cucurbita and an SSR-based genetic linkage map of Cucurbita pepo L.

Science.gov (United States)

Gong, L.; Stift, G.; Kofler, R.; Pachner, M.

2008-01-01

Until recently, only a few microsatellites have been available for Cucurbita, thus their development is highly desirable. The Austrian oil-pumpkin variety Gleisdorfer Ölkürbis (C. pepo subsp. pepo) and the C. moschata cultivar Soler (Puerto Rico) were used for SSR development. SSR-enriched partial genomic libraries were established and 2,400 clones were sequenced. Of these 1,058 (44%) contained an SSR at least four repeats long. Primers were designed for 532 SSRs; 500 primer pairs produced fragments of expected size. Of these, 405 (81%) amplified polymorphic fragments in a set of 12 genotypes: three C. moschata, one C. ecuadorensis, and eight C. pepo representing all eight cultivar groups. On an average, C. pepo and C. moschata produced 3.3 alleles per primer pair, showing high inter-species transferability. There were 187 SSR markers detecting polymorphism between the USA oil-pumpkin variety “Lady Godiva” (O5) and the Italian crookneck variety “Bianco Friulano” (CN), which are the parents of our previous F2 mapping population. It has been used to construct the first published C. pepo map, containing mainly RAPD and AFLP markers. Now the updated map comprises 178 SSRs, 244 AFLPs, 230 RAPDs, five SCARs, and two morphological traits (h and B). It contains 20 linkage groups with a map density of 2.9 cM. The observed genome coverage (Co) is 86.8%. Electronic supplementary material The online version of this article (doi:10.1007/s00122-008-0750-2) contains supplementary material, which is available to authorized users. PMID:18379753

Development of an SSR-based identification key for Tunisian local almonds

Directory of Open Access Journals (Sweden)

Hassouna Gouta

2012-04-01

Full Text Available Ten simple sequence repeat (SSR loci were used to study polymorphism in 54 almond genotypes. All genotypes used in this study originated from almond-growing areas in Tunisia with different climatic conditions ranging from the sub-humid to the arid and are preserved in the national collection at Sidi Bouzid. Using ten SSR, 130 alleles and 250 genotypes were revealed. In order to develop an identification key for each accession, the data were analysed separately for each microsatellite marker. The most polymorphic microsatellite (CPDCT042 was used as a first marker. Two microsatellite loci (CPDCT042 and CPDCT025 were sufficient to discriminate among all accessions studied. Neighbour-joining clustering and principal coordinate analysis were performed to arrange the genotypes according to their genetic relationships and origin. The results are discussed in the context of almond collection management, conformity checks, identification of homonyms, and screening of the local almond germplasm. Furthermore, this microsatellite-based key is a first step toward a marker-assisted identification almond database.

Phylogenetic and Diversity Analysis of Dactylis glomerata Subspecies Using SSR and IT-ISJ Markers.

Science.gov (United States)

Yan, Defei; Zhao, Xinxin; Cheng, Yajuan; Ma, Xiao; Huang, Linkai; Zhang, Xinquan

2016-10-31

The genus Dactylis , an important forage crop, has a wide geographical distribution in temperate regions. While this genus is thought to include a single species, Dactylis glomerata , this species encompasses many subspecies whose relationships have not been fully characterized. In this study, the genetic diversity and phylogenetic relationships of nine representative Dactylis subspecies were examined using SSR and IT-ISJ markers. In total, 21 pairs of SSR primers and 15 pairs of IT-ISJ primers were used to amplify 295 polymorphic bands with polymorphic rates of 100%. The average polymorphic information contents (PICs) of SSR and IT-ISJ markers were 0.909 and 0.780, respectively. The combined data of the two markers indicated a high level of genetic diversity among the nine D. glomerata subspecies, with a Nei's gene diversity index value of 0.283 and Shannon's diversity of 0.448. Preliminarily phylogenetic analysis results revealed that the 20 accessions could be divided into three groups (A, B, C). Furthermore, they could be divided into five clusters, which is similar to the structure analysis with K = 5. Phylogenetic placement in these three groups may be related to the distribution ranges and the climate types of the subspecies in each group. Group A contained eight accessions of four subspecies, originating from the west Mediterranean, while Group B contained seven accessions of three subspecies, originating from the east Mediterranean.

AFLP/SSR mapping of resistance genes to Alectra vogelii in cowpea ...

African Journals Online (AJOL)

To find and map the resistance gene to A. vogelii in cowpea, a F2 population from a cross involving a resistant parent IT81D-994 and a susceptible TVX3236 was screened. Amplified fragment length polymorphism (AFLP) in combination with Single Sequence Repeat (SSR) analysis was used to identify markers that may be ...

In-silico mining, type and frequency analysis of genic microsatellites of finger millet (Eleusine coracana (L.) Gaertn.): a comparative genomic analysis of NBS-LRR regions of finger millet with rice.

Science.gov (United States)

Kalyana Babu, B; Pandey, Dinesh; Agrawal, P K; Sood, Salej; Kumar, Anil

2014-05-01

In recent years, the increased availability of the DNA sequences has given the possibility to develop and explore the expressed sequence tags (ESTs) derived SSR markers. In the present study, a total of 1956 ESTs of finger millet were used to find the microsatellite type, distribution, frequency and developed a total of 545 primer pairs from the ESTs of finger millet. Thirty-two EST sequences had more than two microsatellites and 1357 sequences did not have any SSR repeats. The most frequent type of repeats was trimeric motif, however the second place was occupied by dimeric motif followed by tetra-, hexa- and penta repeat motifs. The most common dimer repeat motif was GA and in case of trimeric SSRs, it was CGG. The EST sequences of NBS-LRR region of finger millet and rice showed higher synteny and were found on nearly same positions on the rice chromosome map. A total of eight, out of 15 EST based SSR primers were polymorphic among the selected resistant and susceptible finger millet genotypes. The primer FMBLEST5 could able to differentiate them into resistant and susceptible genotypes. The alleles specific to the resistant and susceptible genotypes were sequenced using the ABI 3130XL genetic analyzer and found similarity to NBS-LRR regions of rice and finger millet and contained the characteristic kinase-2 and kinase 3a motifs of plant R-genes belonged to NBS-LRR region. The In-silico and comparative analysis showed that the genes responsible for blast resistance can be identified, mapped and further introgressed through molecular breeding approaches for enhancing the blast resistance in finger millet.

Genome Survey Sequencing of Luffa Cylindrica L. and Microsatellite High Resolution Melting (SSR-HRM) Analysis for Genetic Relationship of Luffa Genotypes.

Science.gov (United States)

An, Jianyu; Yin, Mengqi; Zhang, Qin; Gong, Dongting; Jia, Xiaowen; Guan, Yajing; Hu, Jin

2017-09-11

Luffa cylindrica (L.) Roem. is an economically important vegetable crop in China. However, the genomic information on this species is currently unknown. In this study, for the first time, a genome survey of L. cylindrica was carried out using next-generation sequencing (NGS) technology. In total, 43.40 Gb sequence data of L. cylindrica , about 54.94× coverage of the estimated genome size of 789.97 Mb, were obtained from HiSeq 2500 sequencing, in which the guanine plus cytosine (GC) content was calculated to be 37.90%. The heterozygosity of genome sequences was only 0.24%. In total, 1,913,731 contigs (>200 bp) with 525 bp N 50 length and 1,410,117 scaffolds (>200 bp) with 885.01 Mb total length were obtained. From the initial assembled L. cylindrica genome, 431,234 microsatellites (SSRs) (≥5 repeats) were identified. The motif types of SSR repeats included 62.88% di-nucleotide, 31.03% tri-nucleotide, 4.59% tetra-nucleotide, 0.96% penta-nucleotide and 0.54% hexa-nucleotide. Eighty genomic SSR markers were developed, and 51/80 primers could be used in both "Zheda 23" and "Zheda 83". Nineteen SSRs were used to investigate the genetic diversity among 32 accessions through SSR-HRM analysis. The unweighted pair group method analysis (UPGMA) dendrogram tree was built by calculating the SSR-HRM raw data. SSR-HRM could be effectively used for genotype relationship analysis of Luffa species.

Development of SSR markers for the short arm of rye chromosome 1

Czech Academy of Sciences Publication Activity Database

Kofler, R.; Stift, G.; Gong, L.; Suchánková, Pavla; Šimková, Hana; Doležel, Jaroslav; Lelley, T.

2007-01-01

Roč. 71, - (2007), s. 279-281 ISSN 0723-7812 R&D Projects: GA ČR GA521/04/0607 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : SSR markers * rye chromosome 1 Subject RIV: GE - Plant Breeding

PROBLEMS OF THE EFFICIENCY INCREASING OF TRANSPORTATION BY AIR OF UKRAINIAN SSR (1960-1980

Directory of Open Access Journals (Sweden)

Anatoliy Gorban

2015-11-01

Full Text Available The article is devoted to the problems of the efficiency increasing of the air transportation. The difficulties of increasing the efficiency of transportation by air in Ukrainian SSR in 1960-1980 were researched, factors that adversely affected the organization of the transport sector were determined and depicted. The article analyzes what caused such difficulties and it was found out that the causes of these difficulties are connected with the organizational problems of air transport of Ukrainian SSR, which negatively affected the operation of the industry. The central aim of the research is to focus on the main problems of air transport of Ukrainian SSR. So, we should say that the transport operation of those years was distributed too unevenly and was dependent on the population density of the territory of the republic. Purpose of the article is to determine, compile and analyze the factors that negatively affected the organization of air transportation of the Ukrainian republic and reduced the efficiency of its operation. Results of the research shows technical, organization and economical deficiency of air transport of Ukrainian SSR which caused the ineffectiveness of this type of transport and determines the nature of such difficulties. Statement of the problem. During the specified period (1960–1980 the air transport had undergone rapid development. Many new airlines were opened, airports were being built and reconstructed, the terms of exploiting of turbojet aircrafts were increased, the speed of planes was increasing. All these facts ensured safe and reliable air connection of all district centers, connected Ukraine with the other Soviet republics and foreign countries by air corridors. Ukrainian Department of Civil Aviation became the biggest regional Department of the Ministry of Civil Aviation of the USSR. But, at the same time the intensity of the increase of cargo and passenger transportation since 1970s led to accumulation of

La implementación de la política pública de salud sexual y reproductiva (SSR en el Eje Cafetero colombiano: el caso del embarazo adolescente

Directory of Open Access Journals (Sweden)

Sara E. del Castillo Matamoros

2008-05-01

Full Text Available La política nacional de salud sexual y reproductiva (SSR definida en Colombia en 2002 por el Ministerio de la Protección Social para los años 2002 a 2006 señala los temas prioritarios en este campo: maternidad segura, planificación familiar, salud sexual y reproductiva de las y los adolescentes, cáncer de cuello uterino, infecciones de transmisión sexual y reproductiva, VIH/SIDA, y violencia doméstica y sexual. La investigación que se reporta se ha focalizado en el análisis cuantitativo y cualitativo del proceso de implementación de la política de salud sexual y reproductiva de los y las adolescentes en los tres departamentos y capitales que conforman el llamado “Eje Cafetero colombiano”. Los resultados del estudio mostraron que, si bien se mide una reducción en el número de nacimientos en adolescentes (10-19 años en la región vinculada al estudio entre 2003 y 2005, no se pudieron determinar estrategias y actividades explicativas de ello. La política ha permitido visibilizar y legitimar acciones específicas en este campo para la población adolescente. Sin embargo, se observó la existencia de importantes en las metodologías de recolección y sistematización de los datos relativos a la salud sexual y reproductiva de la población adolescente según las entidades estudiadas, así como la ausencia de retroalimentación cuantitativa utilizable para los actores de la política. En conclusión, se emiten unas recomendaciones para el ajuste de dicha política de SSR.

Simple sequence repeat (SSR) markers are effective for identifying ...

African Journals Online (AJOL)

DNA was extracted from newly formed leaves and amplified using 21 simple sequence repeat (SSR) markers (NH001c, NH002b, NH005b, NH007b, NH008b, NH009b, NH011b, NH013b, NH012a, NH014a, NH015a, NH017a, KA4b, KA5, KA14, KA16, KB16, KU10, BGA35, BGT23b and HGA8b). The data was analyzed by ...

Genetic diversity of sweet sorghum germplasm in Mexico using AFLP and SSR markers

Science.gov (United States)

The objective of this work was to evaluate the diversity and genetic relationships between lines and varieties of the sweet sorghum (Sorghum bicolor) germplasm bank of the National Institute for Forestry, Agriculture and Livestock Research, Mexico, using AFLP and SSR markers. The molecular markers ...

Effective damping for SSR analysis of parallel turbine-generators

International Nuclear Information System (INIS)

Agrawal, B.L.; Farmer, R.G.

1988-01-01

Damping is a dominant parameter in studies to determine SSR problem severity and countermeasure requirements. To reach valid conclusions for multi-unit plants, it is essential that the net effective damping of unequally loaded units be known. For the Palo Verde Nuclear Generating Station, extensive testing and analysis have been performed to verify and develop an accurate means of determining the effective damping of unequally loaded units in parallel. This has led to a unique and simple algorithm which correlates well with two other analytic techniques

Comparison of the effectiveness of ISJ and SSR markers and detection of outlier loci in conservation genetics of Pulsatilla patens populations.

Science.gov (United States)

Bilska, Katarzyna; Szczecińska, Monika

2016-01-01

Research into the protection of rare and endangered plant species involves genetic analyses to determine their genetic variation and genetic structure. Various categories of genetic markers are used for this purpose. Microsatellites, also known as simple sequence repeats (SSR), are the most popular category of markers in population genetics research. In most cases, microsatellites account for a large part of the noncoding DNA and exert a neutral effect on the genome. Neutrality is a desirable feature in evaluations of genetic differences between populations, but it does not support analyses of a population's ability to adapt to a given environment or its evolutionary potential. Despite the numerous advantages of microsatellites, non-neutral markers may supply important information in conservation genetics research. They are used to evaluate adaptation to specific environmental conditions and a population's adaptive potential. The aim of this study was to compare the level of genetic variation in Pulsatilla patens populations revealed by neutral SSR markers and putatively adaptive ISJ markers (intron-exon splice junction). The experiment was conducted on 14 Polish populations of P. patens and three P. patens populations from the nearby region of Vitebsk in Belarus. A total of 345 individuals were examined. Analyses were performed with the use of eight SSR primers specific to P. patens and three ISJ primers. SSR markers revealed a higher level of genetic variation than ISJ markers ( H e = 0.609, H e = 0.145, respectively). An analysis of molecular variance (AMOVA) revealed that, the overall genetic diversity between the analyzed populations defined by parameters F ST and Φ PT for SSR (20%) and Φ PT for ISJ (21%) markers was similar. Analysis conducted in the Structure program divided analyzed populations into two groups (SSR loci) and three groups (ISJ markers). Mantel test revealed correlations between the geographic distance and genetic diversity of Polish

Characterization of functional SSR markers in Prosopis alba and their transferability across Prosopis species

Directory of Open Access Journals (Sweden)

María F. Pomponio

2015-08-01

Full Text Available Aim of study: The aim of the study was to characterize functional microsatellite markers in Prosopis alba and examine the transferability to species from the Prosopis genus. Area of the study: samples were obtained from natural populations of Argentina. Material and Methods: Eleven SSR functional markers related to stress and metabolism were amplified in a sample of 152 genotypes from P.alba, P. denudans, P. hassleriP. chilensis, P. flexuosa, and interspecific hybrids. Main results: In P. alba, the PIC average value was 0.36; and 6 out of the 11 primers showed high values of polymorphism ranging from 0.40 to 0.71. The cross-species transferability was high with high percentages of polymorphic loci. Research highlights: The SSR markers developed in P.alba were easily transferred to other Prosopis species which did not have functional markers.

Use of Simple Sequence Repeat (SSR) markers for DNA fingerprinting and diversity analysis of sugarcane (Saccharum spp.) cultivars resistant and susceptible to red rot

Science.gov (United States)

In recent years SSR markers have been used widely for the genetic analysis. The objective of present research was to use SSR markers to develop DNA-based genetic identification and analyze genetic relationship of sugarcane cultivars grown in Pakistan either resistant or susceptible to red rot. Twent...

Analysis of genetic diversity among rapeseed cultivars and breeding lines by srap and ssr molecular markers

International Nuclear Information System (INIS)

Channa, S.A.; Tian, H.

2016-01-01

The knowledge of genetic diversity is very important for developing new rapeseed (Brassica napus L.) cultivars. The genetic diversity among 77 rapeseed accessions, including 22 varieties and 55 advanced breeding lines were analyzed by 47 sequence-related amplified polymorphism (SRAP) and 56 simple sequence repeat (SSR) primers. A total of 270 SRAP and 194 SSR polymorphic fragments were detected with an average of 5.74 and 3.46 for SRAP and SSR primer, respectively. The cluster analysis grouped the 77 accessions into five major clusters. Cluster I contained spring and winter type varieties from Czech Republic and semi-winter varieties and their respective breeding lines from China. The 16 elite breeding lines discovered in Cluster II, III, IV and V indicated higher genetic distance than accessions in Cluster I. The principal component analysis and structure analysis exhibited similar results to the cluster analysis. Analysis of molecular variance revealed that genetic diversity of the selected breeding lines was comparable to the rapeseed varieties, and variation among varieties and lines was significant. The diverse and unique group of 16 elite breeding lines detected in this study can be utilized in the future breeding program as a source for development of commercial varieties with more desirable characters. (author)

[SSR analysis on stress effect of transgenic hybrid poplar 741 on Clostera anachoreta (Fabricius) (Lepidoptera: Notodontidae)].

Science.gov (United States)

Liu, Jun Xia; Song, Xiao Ying; Jiang, Wen Hu; Zhou, Guo Na; Gao, Bao Jia

2016-12-01

The genetic differentiation of the experimental population of Clostera anachoreta fed on different resistant transgenic 741 poplar leaves was analyzed by SSR molecular marker technique to investigate stress effect of transgenic poplar Bt gene as food on target insect. The experimental population of C. anachoreta fed on transgenic 741 poplar high resistant strains 'Pb29', medium resis-tant strains 'Pb17' and non-transgenic poplar (CK), and the screened ten pairs of SSR primers were used. The results showed that 76 alleles were observed in ten pairs of primers. The average allele was 7.6, the average effective number of alleles was 2.2, the average observed heterozygosity was 0.5167, the average expected heterozygosity was 0.5167, and the average percentage of polymorphic loci was 96.7%. The genetic diversity level of C. anachoreta experimental population fed on transgenic poplar 741 was significantly higher than that fed on non-transgenic populations, and C. anachoreta fed on high resistance had the lowest genetic similarity with CK samples, which showed an increasing trend of the genetic diversity of the experimental population fed on transgenic Bt poplar. It was thus clear that transgenic hybrid poplar 741 had stress effects on genetic differentiation of C. anachoreta experimental population by SSR.

Novel STATCOM Controller for Mitigating SSR and Damping Power System Oscillations in a Series Compensated Wind Parks

DEFF Research Database (Denmark)

Bak-Jensen, Birgitte; El-Moursi, M. S.; Abdel-Rahman, Mansour Hassan

2010-01-01

This paper addresses implementation issues associated with a novel damping control algorithm for a STATCOM in a series compensated wind park for mitigating SSR (subsynchronous resonance) and damping power system oscillations. The IEEE first benchmark model on subsynchronous resonance is adopted...... the SSR, damping the power system oscillation and enhancing the transient stability margin in response to different SCRs....... in the STATCOM control structure. The performances of the controllers are tested in steady state operation and in response to system contingencies, taking into account the impact of short circuit ratios (SCRs). Simulation results are presented to demonstrate the capability of the controllers for mitigating...

Development of Pineapple Microsatellite Markers and Germplasm Genetic Diversity Analysis

Directory of Open Access Journals (Sweden)

Suping Feng

2013-01-01

Full Text Available Two methods were used to develop pineapple microsatellite markers. Genomic library-based SSR development: using selectively amplified microsatellite assay, 86 sequences were generated from pineapple genomic library. 91 (96.8% of the 94 Simple Sequence Repeat (SSR loci were dinucleotide repeats (39 AC/GT repeats and 52 GA/TC repeats, accounting for 42.9% and 57.1%, resp., and the other three were mononucleotide repeats. Thirty-six pairs of SSR primers were designed; 24 of them generated clear bands of expected sizes, and 13 of them showed polymorphism. EST-based SSR development: 5659 pineapple EST sequences obtained from NCBI were analyzed; among 1397 nonredundant EST sequences, 843 were found containing 1110 SSR loci (217 of them contained more than one SSR locus. Frequency of SSRs in pineapple EST sequences is 1SSR/3.73 kb, and 44 types were found. Mononucleotide, dinucleotide, and trinucleotide repeats dominate, accounting for 95.6% in total. AG/CT and AGC/GCT were the dominant type of dinucleotide and trinucleotide repeats, accounting for 83.5% and 24.1%, respectively. Thirty pairs of primers were designed for each of randomly selected 30 sequences; 26 of them generated clear and reproducible bands, and 22 of them showed polymorphism. Eighteen pairs of primers obtained by the one or the other of the two methods above that showed polymorphism were selected to carry out germplasm genetic diversity analysis for 48 breeds of pineapple; similarity coefficients of these breeds were between 0.59 and 1.00, and they can be divided into four groups accordingly. Amplification products of five SSR markers were extracted and sequenced, corresponding repeat loci were found and locus mutations are mainly in copy number of repeats and base mutations in the flanking region.

Development of Pineapple Microsatellite Markers and Germplasm Genetic Diversity Analysis

Science.gov (United States)

Tong, Helin; Chen, You; Wang, Jingyi; Chen, Yeyuan; Sun, Guangming; He, Junhu; Wu, Yaoting

2013-01-01

Two methods were used to develop pineapple microsatellite markers. Genomic library-based SSR development: using selectively amplified microsatellite assay, 86 sequences were generated from pineapple genomic library. 91 (96.8%) of the 94 Simple Sequence Repeat (SSR) loci were dinucleotide repeats (39 AC/GT repeats and 52 GA/TC repeats, accounting for 42.9% and 57.1%, resp.), and the other three were mononucleotide repeats. Thirty-six pairs of SSR primers were designed; 24 of them generated clear bands of expected sizes, and 13 of them showed polymorphism. EST-based SSR development: 5659 pineapple EST sequences obtained from NCBI were analyzed; among 1397 nonredundant EST sequences, 843 were found containing 1110 SSR loci (217 of them contained more than one SSR locus). Frequency of SSRs in pineapple EST sequences is 1SSR/3.73 kb, and 44 types were found. Mononucleotide, dinucleotide, and trinucleotide repeats dominate, accounting for 95.6% in total. AG/CT and AGC/GCT were the dominant type of dinucleotide and trinucleotide repeats, accounting for 83.5% and 24.1%, respectively. Thirty pairs of primers were designed for each of randomly selected 30 sequences; 26 of them generated clear and reproducible bands, and 22 of them showed polymorphism. Eighteen pairs of primers obtained by the one or the other of the two methods above that showed polymorphism were selected to carry out germplasm genetic diversity analysis for 48 breeds of pineapple; similarity coefficients of these breeds were between 0.59 and 1.00, and they can be divided into four groups accordingly. Amplification products of five SSR markers were extracted and sequenced, corresponding repeat loci were found and locus mutations are mainly in copy number of repeats and base mutations in the flanking region. PMID:24024187

Genetic Assessment of Moroccan Tomato (Solanum lycopersicum L. Genotypes by RAPD and SSR Markers

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Rajae Amraoui

2017-06-01

Full Text Available For the first time eight local tomato cultivars collected from four different regions of Morocco were assessed with RAPD and SSR methods. Most of RAPD markers give monomorphic banding profiles. Only OPU03 marker showed a total of 4 polymorphic amplicons out of 8 recorded in FIGUIG2 cultivar. The analysis with SSR markers gives more polymorphism. The number of alleles amplified assessed from 2 to 5 alleles among cultivars. The similarity matrix subjected by the unweighted pairgroup arithmetic method (UPGMA clustering grouped the cultivars in four groups where FIGUIG2 cultivar formed a separate and more distant cluster. In addition this cultivar holds the very high percentage of uniformity (99% indicating that is an homogeneous traditional cultivar with high purity. This genotype can be conserved and used in breeding programs. More traditional Moroccan cultivars must be collected in order to determine their genetic structure.

New Hypervariable SSR Markers for Diversity Analysis, Hybrid Purity Testing and Trait Mapping in Pigeonpea [Cajanus cajan (L.) Millspaugh].

Science.gov (United States)

Bohra, Abhishek; Jha, Rintu; Pandey, Gaurav; Patil, Prakash G; Saxena, Rachit K; Singh, Indra P; Singh, D; Mishra, R K; Mishra, Ankita; Singh, F; Varshney, Rajeev K; Singh, N P

2017-01-01

Draft genome sequence in pigeonpea offers unprecedented opportunities for genomics assisted crop improvement via enabling access to genome-wide genetic markers. In the present study, 421 hypervariable simple sequence repeat (SSR) markers from the pigeonpea genome were screened on a panel of eight pigeonpea genotypes yielding marker validation and polymorphism percentages of 95.24 and 54.11%, respectively. The SSR marker assay uncovered a total of 570 alleles with three as an average number of alleles per marker. Similarly, the mean values for gene diversity and PIC were 0.44 and 0.37, respectively. The number of polymorphic markers ranged from 39 to 89 for different parental combinations. Further, 60 of these SSRs were assayed on 94 genotypes, and model based clustering using STRUCTURE resulted in the identification of the two subpopulations ( K = 2). This remained in close agreement with the clustering patterns inferred from genetic distance (GD)-based approaches i.e., dendrogram, factorial and principal coordinate analysis (PCoA). The AMOVA accounted majority of the genetic variation within groups (89%) in comparison to the variation existing between the groups (11%). A subset of these markers was implicated for hybrid purity testing. We also demonstrated utility of these SSR markers in trait mapping through association and bi-parental linkage analyses. The general linear (GLM) and mixed linear (MLM) models both detected a single SSR marker (CcGM03681) with R 2 = 16.4 as associated with the resistance to Fusarium wilt variant 2. Similarly, by using SSR data in a segregating backcross population, the corresponding restorer-of-fertility ( Rf ) locus was putatively mapped at 39 cM with the marker CcGM08896. However, The marker-trait associations (MTAs) detected here represent a very preliminary type and hence demand deeper investigations for conclusive evidence. Given their ability to reveal polymorphism in simple agarose gels, the hypervariable SSRs are valuable

Genetic diversity analysis of Amomum tsao-ko in Jinping County of Yunnan Province using SSR markers

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Ma, Mengli; Wang, Tiantao; Lei, En; Meng, Hengling; Xie, Linyan; Zhu, Kunlong; Duan, Shaoze; Li, Wenqiang; Lu, Bingyue

2017-08-01

Genetic diversity analysis is very important for germplasm resources conservation and utilization. The objective of this study was to assess the genetic diversity among 44 individuals of Amomum tsao-ko from Jinping County of Yunnan Province using 5 selected SSR (simple sequence repeat) markers. A total of 23 polymorphic loci were detected among these germplasms, with an average of 4.6 polymorphic loci per SSR primer combination. The percentage of polymorphic loci was 100%, whereas the mean effective number of alleles (Ne), observed heterozygosity(Ho), expected heterozygosity (He), Shannon's information index (I), and the mean polymorphism information content (PIC) were 3. 410, 0. 491, 0. 679, 1.266 and 0. 672, respectively, indicating that the Amomum tsao-ko germplasms from Jinping County had high genetic diversity.

Development of a core set of SSR markers for the characterization of Gossypium germplasm

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Molecular markers such as simple sequence repeats (SSR) are a useful tool for characterizing genetic diversity of Gossypium germplasm collections. Genetic profiles by DNA fingerprinting of cotton accessions can only be compared among different collections if a common set of molecular markers are us...

Simple sequence repeat (SSR) vs. sequence-related amplified polymorphism (SRAP) markers for Cynara cardunculus characterization

Energy Technology Data Exchange (ETDEWEB)

Casadevall, R.; Martin, E.; Cravero, V.

2011-07-01

A little is known about the genetic variability present in globe artichoke, cultivated and wild cardoons. This knowledge is very important for efficient genetic resources utilization, and to gain a better understanding of genetic structure of this botanical varieties. With the aims to determine genetic distances between Cynara cardunculus accessions and to compare two molecular markers systems for their efficiency to differ between botanical varieties, a molecular characterization of sixteen accessions from different geographical origins was performed. Seven SSR and seven SRAP markers were used for varieties characterization and to calculate genetic distances between them. Both distance matrices were subjected to cluster analysis. Exclusive SSR alleles were found for globe artichoke and for wild cardoon, but non exclusive alleles were found for cultivated cardoon. For both markers systems two major groups were identified, one of them included mostly globe artichoke accessions and the other one grouped mainly cardoons. The differences observed in the sub-cluster conformation with each marker systems may be due to intrinsic characteristics of the markers. Concluding, both kind of molecular markers are valuable tools for studying genetic distances between C. cardunculus accessions although they give different information. Nevertheless, SSR electrophoretic profiles are simpler to score than SRAP markers because they consist of just a few bands. As well, bands are highly informative because of the great number of alleles existing in population and they are codominant markers. In addition, SSRs use would reduce time and costs. (Author) 31 refs.

SSR marker development and intraspecific genetic divergence exploration of Chrysanthemum indicum based on transcriptome analysis.

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Han, Zhengzhou; Ma, Xinye; Wei, Min; Zhao, Tong; Zhan, Ruoting; Chen, Weiwen

2018-04-25

Chrysanthemum indicum L., an important ancestral species of the flowering plant chrysanthemum, can be used as medicine and for functional food development. Due to the lack of hereditary information for this species and the difficulty of germplasm identification, we herein provide new genetic insight from the perspective of intraspecific transcriptome comparison and present single sequence repeat (SSR) molecular marker recognition technology. Through the study of a diploid germplasm (DIWNT) and a tetraploid germplasm (DIWT), the following outcome were obtained. (1) A significant difference in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations for specific homologous genes was observed using the OrthoMCL method for the identification of homologous gene families between the two cytotypes. Ka/Ks analysis of common, single-copy homologous family members also revealed a greater difference among genes that experienced positive selection than among those experiencing positive selection. (2) Of more practical value, 2575 SSR markers were predicted and partly verified. We used TaxonGap as a visual tool to inspect genotype uniqueness and screen for high-performance molecular loci; we recommend four primers of 65 randomly selected primers with a combined identification success rate of 88.6% as priorities for further development of DNA fingerprinting of C. indicum germplasm. The SSR technology based on next-generation sequencing was proved to be successful in the identification of C. indicum germplasms. And the information on the intraspecfic genetic divergence generated by transcriptome comparison deepened the understanding of this complex species' nature.

Generation of Unbiased Ionospheric Corrections in Brazilian Region for GNSS positioning based on SSR concept

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Monico, J. F. G.; De Oliveira, P. S., Jr.; Morel, L.; Fund, F.; Durand, S.; Durand, F.

2017-12-01

Mitigation of ionospheric effects on GNSS (Global Navigation Satellite System) signals is very challenging, especially for GNSS positioning applications based on SSR (State Space Representation) concept, which requires the knowledge of spatial correlated errors with considerable accuracy level (centimeter). The presence of satellite and receiver hardware biases on GNSS measurements difficult the proper estimation of ionospheric corrections, reducing their physical meaning. This problematic can lead to ionospheric corrections biased of several meters and often presenting negative values, which is physically not possible. In this contribution, we discuss a strategy to obtain SSR ionospheric corrections based on GNSS measurements from CORS (Continuous Operation Reference Stations) Networks with minimal presence of hardware biases and consequently physical meaning. Preliminary results are presented on generation and application of such corrections for simulated users located in Brazilian region under high level of ionospheric activity.

Mining and Development of Novel SSR Markers Using Next Generation Sequencing (NGS Data in Plants

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Sima Taheri

2018-02-01

Full Text Available Microsatellites, or simple sequence repeats (SSRs, are one of the most informative and multi-purpose genetic markers exploited in plant functional genomics. However, the discovery of SSRs and development using traditional methods are laborious, time-consuming, and costly. Recently, the availability of high-throughput sequencing technologies has enabled researchers to identify a substantial number of microsatellites at less cost and effort than traditional approaches. Illumina is a noteworthy transcriptome sequencing technology that is currently used in SSR marker development. Although 454 pyrosequencing datasets can be used for SSR development, this type of sequencing is no longer supported. This review aims to present an overview of the next generation sequencing, with a focus on the efficient use of de novo transcriptome sequencing (RNA-Seq and related tools for mining and development of microsatellites in plants.

Assessment of genetic diversity in ragi [Eleusine coracana (L.) Gaertn] using morphological, RAPD and SSR markers.

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Prabhu, Kalapad Santosh; Das, Anath Bandhu; Dikshit, Nilamani

2018-04-25

Finger millet (Eleusine coracana L. Gaertn., 2n=36) is one of the most important minor crops, commonly known as 'ragi' and used as a staple food grain in more than 25 countries including Africa and south Asia. Twenty-seven accessions of ragi were collected from different parts of India and were evaluated for morpho-genetic diversity studies. Simple sequence repeat (SSR) and random amplified polymorphic DNA (RAPD) markers were used for assessment of genetic diversity among 27 genotypes of E. coracana. High degree of similarity (90%) was obtained between 'IC49979A' and 'IC49974B' genotypes, whereas low level of similarity (9.09%) was found between 'IC204141' and 'IC49985' as evident in morphological and DNA markers. A total of 64 SSR and 301 RAPD amplicons were produced, out of which 87.50% and 77.20% DNA fragments showed polymorphism, respectively. The clustering pattern obtained among the genotypes corresponded well with their morphological and cytological data with a monophyletic origin of this species which was further supported by high bootstrap values and principal component analysis. Cluster analysis showed that ragi accessions were categorised into three distinct groups. Genotypes IC344761, IC340116, IC340127, IC49965 and IC49985 found accession specific in RAPD and SSR markers. The variation among ragi accessions might be used as potential source of germplasm for crop improvement.

Genetic Characterization of Turkish Snake Melon (Cucumis melo L. subsp. melo flexuosus Group) Accessions Revealed by SSR Markers.

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Solmaz, Ilknur; Kacar, Yildiz Aka; Simsek, Ozhan; Sari, Nebahat

2016-08-01

Snake melon is an important cucurbit crop especially in the Southeastern and the Mediterranean region of Turkey. It is consumed as fresh or pickled. The production is mainly done with the local landraces in the country. Turkey is one of the secondary diversification centers of melon and possesses valuable genetic resources which have different morphological characteristics in case of snake melon. Genetic diversity of snake melon genotypes collected from different regions of Turkey and reference genotypes obtained from World Melon Gene Bank in Avignon-France was examined using 13 simple sequence repeat (SSR) markers. A total of 69 alleles were detected, with an average of 5.31 alleles per locus. The polymorphism information content of SSR markers ranged from 0.19 to 0.57 (average 0.38). Based on cluster analysis, two major groups were defined. The first major group included only one accession (61), while the rest of all accessions grouped in the second major group and separated into different sub-clusters. Based on SSR markers, cluster analysis indicated that considerably high genetic variability exists among the examined accessions; however, Turkish snake melon accessions were grouped together with the reference snake melon accessions.

Gene mining a marama bean expressed sequence tags (ESTs ...

African Journals Online (AJOL)

The authors reported the identification of genes associated with embryonic development and microsatellite sequences. The future direction will entail characterization of these genes using gene over-expression and mutant assays. Key words: Namibia, simple sequence repeats (SSR), data mining, homology searches, ...

Use of genome sequence data in the design and testing of SSR markers for Phytophthora species

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Cardle Linda

2008-12-01

Full Text Available Abstract Background Microsatellites or single sequence repeats (SSRs are a powerful choice of marker in the study of Phytophthora population biology, epidemiology, ecology, genetics and evolution. A strategy was tested in which the publicly available unigene datasets extracted from genome sequences of P. infestans, P. sojae and P. ramorum were mined for candidate SSR markers that could be applied to a wide range of Phytophthora species. Results A first approach, aimed at the identification of polymorphic SSR loci common to many Phytophthora species, yielded 171 reliable sequences containing 211 SSRs. Microsatellites were identified from 16 target species representing the breadth of diversity across the genus. Repeat number ranged from 3 to 16 with most having seven repeats or less and four being the most commonly found. Trinucleotide repeats such as (AAGn, (AGGn and (AGCn were the most common followed by pentanucleotide, tetranucleotide and dinucleotide repeats. A second approach was aimed at the identification of useful loci common to a restricted number of species more closely related to P. sojae (P. alni, P. cambivora, P. europaea and P. fragariae. This analysis yielded 10 trinucleotide and 2 tetranucleotide SSRs which were repeated 4, 5 or 6 times. Conclusion Key studies on inter- and intra-specific variation of selected microsatellites remain. Despite the screening of conserved gene coding regions, the sequence diversity between species was high and the identification of useful SSR loci applicable to anything other than the most closely related pairs of Phytophthora species was challenging. That said, many novel SSR loci for species other than the three 'source species' (P. infestans, P. sojae and P. ramorum are reported, offering great potential for the investigation of Phytophthora populations. In addition to the presence of microsatellites, many of the amplified regions may represent useful molecular marker regions for other studies as

An EST dataset for Metasequoia glyptostroboides buds: the first EST resource for molecular genomics studies in Metasequoia.

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Zhao, Ying; Thammannagowda, Shivegowda; Staton, Margaret; Tang, Sha; Xia, Xinli; Yin, Weilun; Liang, Haiying

2013-03-01

The "living fossil" Metasequoia glyptostroboides Hu et Cheng, commonly known as dawn redwood or Chinese redwood, is the only living species in the genus and is valued for its essential oil and crude extracts that have great potential for anti-fungal activity. Despite its paleontological significance and economical value as a rare relict species, genomic resources of Metasequoia are very limited. In order to gain insight into the molecular mechanisms behind the formation of reproductive buds and the transition from vegetative phase to reproductive phase in Metasequoia, we performed sequencing of expressed sequence tags from Metasequoia vegetative buds and female buds. By using the 454 pyrosequencing technology, a total of 1,571,764 high-quality reads were generated, among which 733,128 were from vegetative buds and 775,636 were from female buds. These EST reads were clustered and assembled into 114,124 putative unique transcripts (PUTs) with an average length of 536 bp. The 97,565 PUTs that were at least 100 bp in length were functionally annotated by a similarity search against public databases and assigned with Gene Ontology (GO) terms. A total of 59 known floral gene families and 190 isotigs involved in hormone regulation were captured in the dataset. Furthermore, a set of PUTs differentially expressed in vegetative and reproductive buds, as well as SSR motifs and high confidence SNPs, were identified. This is the first large-scale expressed sequence tags ever generated in Metasequoia and the first evidence for floral genes in this critically endangered deciduous conifer species.

Table 1. Details of SSR loci genotyped in E. tereticornis (Et86)

Indian Academy of Sciences (India)

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Details of SSR loci genotyped in E. tereticornis (Et86) × E. grandis (Eg9) mapping population showing allelic pattern, annealing temperature (oC) and linkage group (LG). Marker name. Et86. Eg9. Annealing temperature. (oC). LG. 1. EMBRA2 ab cd. 56. 11. 2. EMBRA9 nn np. 57. 5. 3. EMBRA17 lm ll. 56. 9. 4. EMBRA19 lm.

EST2Prot: Mapping EST sequences to proteins

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Lin David M

2006-03-01

Full Text Available Abstract Background EST libraries are used in various biological studies, from microarray experiments to proteomic and genetic screens. These libraries usually contain many uncharacterized ESTs that are typically ignored since they cannot be mapped to known genes. Consequently, new discoveries are possibly overlooked. Results We describe a system (EST2Prot that uses multiple elements to map EST sequences to their corresponding protein products. EST2Prot uses UniGene clusters, substring analysis, information about protein coding regions in existing DNA sequences and protein database searches to detect protein products related to a query EST sequence. Gene Ontology terms, Swiss-Prot keywords, and protein similarity data are used to map the ESTs to functional descriptors. Conclusion EST2Prot extends and significantly enriches the popular UniGene mapping by utilizing multiple relations between known biological entities. It produces a mapping between ESTs and proteins in real-time through a simple web-interface. The system is part of the Biozon database and is accessible at http://biozon.org/tools/est/.

Changes in allelic frequency over time in European bread wheat (Triticum aestivum L.) varieties revealed using DArT and SSR markers

DEFF Research Database (Denmark)

Orabi, Jihad; Jahoor, Ahmed; Backes, Gunter Martin

2014-01-01

A collection of 189 bread wheat landraces and cultivars, primarily of European origin, released between 1886 and 2009, was analyzed using two DNA marker systems. A set of 76 SSR markers and ~7,000 DArT markers distributed across the wheat genome were employed in these analyses. All of the SSR...... markers were found to be polymorphic, whereas only 2,532 of the ~7,000 DArT markers were polymorphic. A Mantel test between the genetic distances calculated based on the SSR and DArT data showed a strong positive correlation between the two marker types, with a Pearson's value (r) of 0.66. We assessed...... the genetic diversity and allelic frequencies among the accessions based on spring- versus winter-wheat type as well as between landraces and cultivars. We also analyzed the changes in genetic diversity and allelic frequencies in these samples over time. We observed separation based on both vernalization type...

Analysis of average standardized SSR allele size supports domestication of soybean along the Yellow River

NARCIS (Netherlands)

Li, Y.H.; Zhang, C.; Smulders, M.J.M.; Li, W.; Ma, Y.S.; Xu, Qu; Chang, R.Z.; Qiu, Li-Juan

2013-01-01

Soybean (Glycine max) was domesticated in China from its wild progenitor G. soja. The geographic region of domestication is, however, not exactly known. Here we employed the directional evolution of SSR (microsatellite) repeats (which mutate preferentially into longer alleles) to analyze the

Microsatellite DNA in genomic survey sequences and UniGenes of loblolly pine

Science.gov (United States)

Craig S Echt; Surya Saha; Dennis L Deemer; C Dana Nelson

2011-01-01

Genomic DNA sequence databases are a potential and growing resource for simple sequence repeat (SSR) marker development in loblolly pine (Pinus taeda L.). Loblolly pine also has many expressed sequence tags (ESTs) available for microsatellite (SSR) marker development. We compared loblolly pine SSR densities in genome survey sequences (GSSs) to those in non-redundant...

Transferability of Newly Developed Pear SSR Markers to Other Rosaceae Species.

Science.gov (United States)

Fan, L; Zhang, M-Y; Liu, Q-Z; Li, L-T; Song, Y; Wang, L-F; Zhang, S-L; Wu, J

2013-01-01

A set of 120 simple sequence repeats (SSRs) was developed from the newly assembled pear sequence and evaluated for polymorphisms in seven genotypes of pear from different genetic backgrounds. Of these, 67 (55.8 %) primer pairs produced polymorphic amplifications. Together, the 67 SSRs detected 277 alleles with an average of 4.13 per locus. Sequencing of the amplification products from randomly picked loci NAUPy31a and NAUpy53a verified the presence of the SSR loci. When the 67 primer pairs were tested on 96 individual members of eight species in the Rosaceae family, 61.2 % (41/67) of the tested SSRs successfully amplified a PCR product in at least one of the Rosaceae genera. The transferability from pear to different species varied from 58.2 % (apple) to 11.9 % (cherry). The ratio of transferability also reflected the closer relationships within Maloideae over Prunoideae. Two pear SSR markers, NAUpy43c and NAUpy55k, could distinguish the 20 different apple genotypes thoroughly, and UPGMA cluster analysis grouped them into three groups at the similarity level of 0.56. The high level of polymorphism and good transferability of pear SSRs to Rosaceae species indicate their promise for application to future molecular screening, map construction, and comparative genomic studies among pears and other Rosaceae species.

High-density Integrated Linkage Map Based on SSR Markers in Soybean

Science.gov (United States)

Hwang, Tae-Young; Sayama, Takashi; Takahashi, Masakazu; Takada, Yoshitake; Nakamoto, Yumi; Funatsuki, Hideyuki; Hisano, Hiroshi; Sasamoto, Shigemi; Sato, Shusei; Tabata, Satoshi; Kono, Izumi; Hoshi, Masako; Hanawa, Masayoshi; Yano, Chizuru; Xia, Zhengjun; Harada, Kyuya; Kitamura, Keisuke; Ishimoto, Masao

2009-01-01

A well-saturated molecular linkage map is a prerequisite for modern plant breeding. Several genetic maps have been developed for soybean with various types of molecular markers. Simple sequence repeats (SSRs) are single-locus markers with high allelic variation and are widely applicable to different genotypes. We have now mapped 1810 SSR or sequence-tagged site markers in one or more of three recombinant inbred populations of soybean (the US cultivar ‘Jack’ × the Japanese cultivar ‘Fukuyutaka’, the Chinese cultivar ‘Peking’ × the Japanese cultivar ‘Akita’, and the Japanese cultivar ‘Misuzudaizu’ × the Chinese breeding line ‘Moshidou Gong 503’) and have aligned these markers with the 20 consensus linkage groups (LGs). The total length of the integrated linkage map was 2442.9 cM, and the average number of molecular markers was 90.5 (range of 70–114) for the 20 LGs. We examined allelic diversity for 1238 of the SSR markers among 23 soybean cultivars or lines and a wild accession. The number of alleles per locus ranged from 2 to 7, with an average of 2.8. Our high-density linkage map should facilitate ongoing and future genomic research such as analysis of quantitative trait loci and positional cloning in addition to marker-assisted selection in soybean breeding. PMID:19531560

Association Analysis of SSR Markers with Phenology, Grain, and Stover-Yield Related Traits in Pearl Millet (Pennisetum glaucum (L. R. Br.

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Baskaran Kannan

2014-01-01

Full Text Available Pearl millet is a staple food crop for millions of people living in the arid and semi-arid tropics. Molecular markers have been used to identify genomic regions linked to traits of interest by conventional QTL mapping and association analysis. Phenotypic recurrent selection is known to increase frequencies of favorable alleles and decrease those unfavorable for the traits under selection. This study was undertaken (i to quantify the response to recurrent selection for phenotypic traits during breeding of the pearl millet open-pollinated cultivar “CO (Cu 9” and its four immediate progenitor populations and (ii to assess the ability of simple sequence repeat (SSR marker alleles to identify genomic regions linked to grain and stover yield-related traits in these populations by association analysis. A total of 159 SSR alleles were detected across 34 selected single-copy SSR loci. SSR marker data revealed presence of subpopulations. Association analysis identified genomic regions associated with flowering time located on linkage group (LG 6 and plant height on LG4, LG6, and LG7. Marker alleles on LG6 were associated with stover yield, and those on LG7 were associated with grain yield. Findings of this study would give an opportunity to develop marker-assisted recurrent selection (MARS or marker-assisted population improvement (MAPI strategies to increase the rate of gain for pearl millet populations undergoing recurrent selection.

Genetic Diversity of Namibian Pennisetum glaucum (L.) R. BR. (Pearl Millet) Landraces Analyzed by SSR and Morphological Markers.

Science.gov (United States)

McBenedict, Billy; Chimwamurombe, Percy; Kwembeya, Ezekeil; Maggs-Kölling, Gillian

2016-01-01

Current Pennisetum glaucum (L.) R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation's food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs) and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA) on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia.

Genetic Diversity of Namibian Pennisetum glaucum (L. R. BR. (Pearl Millet Landraces Analyzed by SSR and Morphological Markers

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Billy McBenedict

2016-01-01

Full Text Available Current Pennisetum glaucum (L. R. BR. cultivars in Namibia have overall poor performance posing a threat to the nation’s food security because this crop is staple for over 70% of the Namibian population. The crop suffers from undesirable production traits such as susceptibility to diseases, low yield, and prolonged reproductive cycle. This study aimed to understand the genetic diversity of the crop in Namibia by simple sequence repeats (SSRs and morphology analysis. A total of 1441 genotypes were collected from the National Gene Bank representing all the Namibian landraces. A sample of 96 genotypes was further analyzed by SSR using Shannon-Wiener diversity index and revealed a value of 0.45 indicating low genetic diversity. Ordination using Principal Coordinate Analysis (PCoA on SSR data confirmed clusters generated by UPGMA for the 96 P. glaucum accessions. UPGMA phenograms of 29 morphological characterized genotypes were generated for SSR and morphology data and the two trees revealed 78% resemblance. Lodging susceptibility, tillering attitude, spike density, fodder yield potential, early vigour, and spike shape were the phenotypic characters upon which some clusters were based in both datasets. It is recommended that efforts should be made to widen the current gene pool in Namibia.

Tagging and mapping of SSR marker for rust resistance gene in lentil (Lens culinaris Medikus subsp. culinaris).

Science.gov (United States)

Dikshit, H K; Singh, Akanksha; Singh, D; Aski, M; Jain, Neelu; Hegde, V S; Basandrai, A K; Basandrai, D; Sharma, T R

2016-06-01

Lentil, as an economical source of protein, minerals and vitamins, plays important role in nutritional security of the common man. Grown mainly in West Asia, North Africa (WANA) region and South Asia, it suffers from several biotic stresses such as wilt, rust, blight and broomrape. Lentil rust caused by autoecious fungus Uromyces viciae fabae (Pers.) Schroet is a serious lentil disease in Algeria, Bangladesh, Ethiopia, India, Italy, Morocco, Pakistan and Nepal. The disease symptoms are observed during flowering and early podding stages. Rust causes severe yield losses in lentil. It can only be effectively controlled by identifying the resistant source, understanding its inheritance and breeding for host resistance. The obligate parasitic nature of pathogen makes it difficult to maintain the pathogen in culture and to apply it to screen segregating progenies under controlled growth conditions. Hence, the use of molecular markers will compliment in identification of resistant types in different breeding programs. Here, we studied the inheritance of resistance to rust in lentil using F₁, F₂ and F₂:₃ from cross PL 8 (susceptible) x L 4149 (resistant) varieties. The phenotyping of lentil population was carried out at Sirmour, India. The result of genetic analysis revealed that a single dominant gene controls rust resistance in lentil genotype L 4149. The F2 population from this cross was used to tag and map the rust resistance gene using SSR and SRAP markers. Markers such as 270 SRAP and 162 SSR were studied for polymorphism and 101 SRAP and 33 SSRs were found to be polymorphic between the parents. Two SRAP and two SSR markers differentiated the resistant and susceptible bulks. SSR marker Gllc 527 was estimated to be linked to rust resistant locus at a distance of 5.9 cM. The Gllc 527 marker can be used for marker assisted selection for rust resistance; however, additional markers closer to rust resistant locus are required. The markers linked to the rust

Construction of a SNP and SSR linkage map in autotetraploid blueberry using genotyping by sequencing

Science.gov (United States)

A mapping population developed from a cross between two key highbush blueberry cultivars, Draper × Jewel (Vaccinium corymbosum), segregating for a number of important phenotypic traits, has been utilized to produce a genetic linkage map. Data on 233 single sequence repeat (SSR) markers and 1794 sing...

De novo Assembly, Characterization of Immature Seed Transcriptome and Development of Genic-SSR Markers in Black Gram [Vigna mungo (L. Hepper].

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J Souframanien

Full Text Available Black gram [V. mungo (L. Hepper] is an important legume crop extensively grown in south and south-east Asia, where it is a major source of dietary protein for its predominantly vegetarian population. However, lack of genomic information and markers has become a limitation for genetic improvement of this crop. Here, we report the transcriptome sequencing of the immature seeds of black gram cv. TU94-2, by Illumina paired end sequencing technology to generate transcriptome sequences for gene discovery and genic-SSR marker development. A total of 17.2 million paired-end reads were generated and 48,291 transcript contigs (TCS were assembled with an average length of 443 bp. Based on sequence similarity search, 33,766 TCS showed significant similarity to known proteins. Among these, only 29,564 TCS were annotated with gene ontology (GO functional categories. A total number of 138 unique KEGG (Kyoto Encyclopedia of Genes and Genomes pathways were identified, of which majority of TCS are grouped into purine metabolism (678 followed by pyrimidine metabolism (263. A total of 48,291 TCS were searched for SSRs and 1,840 SSRs were identified in 1,572 TCS with an average frequency of one SSR per 11.9 kb. The tri-nucleotide repeats were most abundant (35% followed by di-nucleotide repeats (32%. PCR primer pairs were successfully designed for 933 SSR loci. Sequences analyses indicate that about 64.4% and 35.6% of the SSR motifs were present in the coding sequences (CDS and untranslated regions (UTRs respectively. Tri-nucleotide repeats (57.3% were preferentially present in the CDS. The rate of successful amplification and polymorphism were investigated using selected primers among 18 black gram accessions. Genic-SSR markers developed from the Illumina paired end sequencing of black gram immature seed transcriptome will provide a valuable resource for genetic diversity, evolution, linkage mapping, comparative genomics and marker-assisted selection in black gram.

De novo Assembly, Characterization of Immature Seed Transcriptome and Development of Genic-SSR Markers in Black Gram [Vigna mungo (L.) Hepper

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Souframanien, J.; Reddy, Kandali Sreenivasulu

2015-01-01

Black gram [V. mungo (L.) Hepper] is an important legume crop extensively grown in south and south-east Asia, where it is a major source of dietary protein for its predominantly vegetarian population. However, lack of genomic information and markers has become a limitation for genetic improvement of this crop. Here, we report the transcriptome sequencing of the immature seeds of black gram cv. TU94-2, by Illumina paired end sequencing technology to generate transcriptome sequences for gene discovery and genic-SSR marker development. A total of 17.2 million paired-end reads were generated and 48,291 transcript contigs (TCS) were assembled with an average length of 443 bp. Based on sequence similarity search, 33,766 TCS showed significant similarity to known proteins. Among these, only 29,564 TCS were annotated with gene ontology (GO) functional categories. A total number of 138 unique KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways were identified, of which majority of TCS are grouped into purine metabolism (678) followed by pyrimidine metabolism (263). A total of 48,291 TCS were searched for SSRs and 1,840 SSRs were identified in 1,572 TCS with an average frequency of one SSR per 11.9 kb. The tri-nucleotide repeats were most abundant (35%) followed by di-nucleotide repeats (32%). PCR primer pairs were successfully designed for 933 SSR loci. Sequences analyses indicate that about 64.4% and 35.6% of the SSR motifs were present in the coding sequences (CDS) and untranslated regions (UTRs) respectively. Tri-nucleotide repeats (57.3%) were preferentially present in the CDS. The rate of successful amplification and polymorphism were investigated using selected primers among 18 black gram accessions. Genic-SSR markers developed from the Illumina paired end sequencing of black gram immature seed transcriptome will provide a valuable resource for genetic diversity, evolution, linkage mapping, comparative genomics and marker-assisted selection in black gram. PMID

An Efficient Strategy Combining SSR Markers- and Advanced QTL-seq-driven QTL Mapping Unravels Candidate Genes Regulating Grain Weight in Rice.

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Daware, Anurag; Das, Sweta; Srivastava, Rishi; Badoni, Saurabh; Singh, Ashok K; Agarwal, Pinky; Parida, Swarup K; Tyagi, Akhilesh K

2016-01-01

Development and use of genome-wide informative simple sequence repeat (SSR) markers and novel integrated genomic strategies are vital to drive genomics-assisted breeding applications and for efficient dissection of quantitative trait loci (QTLs) underlying complex traits in rice. The present study developed 6244 genome-wide informative SSR markers exhibiting in silico fragment length polymorphism based on repeat-unit variations among genomic sequences of 11 indica, japonica, aus , and wild rice accessions. These markers were mapped on diverse coding and non-coding sequence components of known cloned/candidate genes annotated from 12 chromosomes and revealed a much higher amplification (97%) and polymorphic potential (88%) along with wider genetic/functional diversity level (16-74% with a mean 53%) especially among accessions belonging to indica cultivar group, suggesting their utility in large-scale genomics-assisted breeding applications in rice. A high-density 3791 SSR markers-anchored genetic linkage map (IR 64 × Sonasal) spanning 2060 cM total map-length with an average inter-marker distance of 0.54 cM was generated. This reference genetic map identified six major genomic regions harboring robust QTLs (31% combined phenotypic variation explained with a 5.7-8.7 LOD) governing grain weight on six rice chromosomes. One strong grain weight major QTL region ( OsqGW5.1 ) was narrowed-down by integrating traditional QTL mapping with high-resolution QTL region-specific integrated SSR and single nucleotide polymorphism markers-based QTL-seq analysis and differential expression profiling. This led us to delineate two natural allelic variants in two known cis -regulatory elements (RAV1AAT and CARGCW8GAT) of glycosyl hydrolase and serine carboxypeptidase genes exhibiting pronounced seed-specific differential regulation in low (Sonasal) and high (IR 64) grain weight mapping parental accessions. Our genome-wide SSR marker resource (polymorphic within/between diverse

Desenho e validação de iniciadores microssatélites SSR para mamoneira

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Edna Lôbo Machado

2013-11-01

Full Text Available O objetivo deste trabalho foi desenhar, validar e otimizar pares de iniciadores microssatélites SSR para mamoneira. O desenho dos pares de iniciadores foi feito por meio do aplicativo Websat, a partir de sequências depositadas no GenBank do National Center for Biotechnology Information (GenBank/NCBI, e a sua qualidade foi aferida com uso do aplicativo web NetPrimer. Foram utilizadas diferentes concentrações de DNA, cloreto de magnésio, pares de iniciadores, dNTPs e temperatura de anelamento para otimização das condições de PCR. Um total de 30 pares de iniciadores SSR foi desenhado, sintetizado e otimizado. O gel de agarose foi utilizado para detecção dos produtos amplificados, e o gel desnaturante de poliacrilamida, na otimização das condições de PCR e na identificação de polimorfismo. Os pares de iniciadores apresentaram percentagem média de guanina/citosina (GC igual a 47,29% e produtos amplificados com tamanhos entre 128 e 381 pb. Vinte e nove pares de iniciadores SSR (96,7% foram validados, dos quais nove foram polimórficos (23,3%. As concentrações otimizadas para amplificação são: DNA, 25 ng; cloreto de magnésio, 1,2 mmol L-1; iniciadores Forward e Reverse, 0,4 mmol L-1; dNTPs, 0,1 mmol L-1; e temperatura de anelamento, 62 a 64ºC. As ferramentas de bioinformática Websat e Net Primer podem ser utilizadas para desenvolver iniciadores microssatélites de qualidade, para a mamoneira, a partir de sequências depositadas no GenBank/NCBI.

Crystallization and preliminary X-ray crystallographic analysis of EstE1, a new and thermostable esterase cloned from a metagenomic library

Energy Technology Data Exchange (ETDEWEB)

Byun, Jung-Sue [Department of Biology, Yonsei University, Seoul 120-749 (Korea, Republic of); Protein Network Research Center, Yonsei University, Seoul 120-749 (Korea, Republic of); Rhee, Jin-Kyu [Department of Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Dong-Uk [Department of Biology, Yonsei University, Seoul 120-749 (Korea, Republic of); Oh, Jong-Won [Department of Biotechnology, Yonsei University, Seoul 120-749 (Korea, Republic of); Cho, Hyun-Soo, E-mail: hscho8@yonsei.ac.kr [Department of Biology, Yonsei University, Seoul 120-749 (Korea, Republic of); Protein Network Research Center, Yonsei University, Seoul 120-749 (Korea, Republic of)

2006-02-01

Recombinant EstE1 protein with a histidine tag at the C-terminus was overexpressed in Escherichia coli strain BL21(DE3) and then purified by affinity chromatography. The protein was then crystallized at 290 K by the hanging-drop vapour-diffusion method. EstE1, a new thermostable esterase, was isolated by functional screening of a metagenomic DNA library from thermal environment samples. This enzyme showed activity towards short-chain acyl derivatives of length C4–C6 at a temperature of 303–363 K and displayed a high thermostability above 353 K. EstE1 has 64 and 57% amino-acid sequence similarity to est{sub pc}-encoded carboxylesterase from Pyrobaculum calidifontis and AFEST from Archaeoglobus fulgidus, respectively. The recombinant protein with a histidine tag at the C-terminus was overexpressed in Escherichia coli strain BL21(DE3) and then purified by affinity chromatography. The protein was crystallized at 290 K by the hanging-drop vapour-diffusion method. X-ray diffraction data were collected to 2.3 Å resolution from an EstE1 crystal; the crystal belongs to space group P4{sub 1}2{sub 1}2, with unit-cell parameters a = b = 73.71, c = 234.23 Å. Assuming the presence of four molecules in the asymmetric unit, the Matthews coefficient V{sub M} is calculated to be 2.2 Å{sup 3} Da{sup −1} and the solvent content is 44.1%.

Development of SSR Markers Linked to Low Hydrocyanic Acid Content in Sorghum-Sudan Grass Hybrid Based on BSA Method.

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Xiao-Xia, Yu; Zhi-Hua, Liu; Zhuo, Yu; Yue, Shi; Xiao-Yu, Li

2016-01-01

Sorghum-Sudan grass hybrid containing high hydrocyanic acid content can cause hydrocyanic acid poisoning to the livestock and limit the popularization of this forage crop. Molecular markers associated with low hydrocyanic acid content can speed up the process of identification of genotypes with low hydrocyanic acid content. In the present study, 11 polymorphic SSR primers were screened and used for bulked segregant analysis and single marker analysis. Three SSR markers Xtxp7230, Xtxp7375 and Bnlg667960 associated with low hydrocyanic acid content were rapidly identified by BSA. In single marker analysis, six markers Xtxp7230, Xtxp7375, Bnlg667960, Xtxp67-11, Xtxp295-7 and Xtxp12-9 were linked to low hydrocyanic acid content, which explained the proportion of phenotypic variation from 7.6 % to 41.2 %. The markers identified by BSA were also verified by single marker analysis. The three SSR marker bands were then cloned and sequenced for sequence homology analysis in NCBI. It is the first report on the development of molecular markers associated with low hydrocyanic acid content in sorghum- Sudan grass hybrid. These markers will be useful for genetic improvement of low hydrocyanic acid sorghum-Sudan grass hybrid by marker-assisted breeding.

Development of polymorphic genic-SSR markers by cDNA library sequencing in boxwood, Buxus spp. (Buxaceae)

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Genic microsatellites or simple sequence repeat (genic-SSR) markers were developed in boxwood (Buxus taxa) for genetic diversity analysis, identification of taxa, and to facilitate breeding. cDNA libraries were developed from mRNA extracted from leaves of Buxus sempervirens ‘Vardar Valley’ and seque...

Genotype-specific microsatellite (SSR) markers for the sugarcane germplasm in the Karst region of Guizhou, China

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It is the first report on SSR-based molecular evaluation of genetic variability among sugarcane genotypes from the Karst region of China that provides useful information for local sugarcane improvement. Eighteen sugarcane genotypes including 13 active cultivars and five elite QT-series clones bred l...

SSR-based genetic diversity and structure of garlic accessions from Brazil.

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da Cunha, Camila Pinto; Resende, Francisco Vilela; Zucchi, Maria Imaculada; Pinheiro, José Baldin

2014-10-01

Garlic is a spice and a medicinal plant; hence, there is an increasing interest in 'developing' new varieties with different culinary properties or with high content of nutraceutical compounds. Phenotypic traits and dominant molecular markers are predominantly used to evaluate the genetic diversity of garlic clones. However, 24 SSR markers (codominant) specific for garlic are available in the literature, fostering germplasm researches. In this study, we genotyped 130 garlic accessions from Brazil and abroad using 17 polymorphic SSR markers to assess the genetic diversity and structure. This is the first attempt to evaluate a large set of accessions maintained by Brazilian institutions. A high level of redundancy was detected in the collection (50 % of the accessions represented eight haplotypes). However, non-redundant accessions presented high genetic diversity. We detected on average five alleles per locus, Shannon index of 1.2, HO of 0.5, and HE of 0.6. A core collection was set with 17 accessions, covering 100 % of the alleles with minimum redundancy. Overall FST and D values indicate a strong genetic structure within accessions. Two major groups identified by both model-based (Bayesian approach) and hierarchical clustering (UPGMA dendrogram) techniques were coherent with the classification of accessions according to maturity time (growth cycle): early-late and midseason accessions. Assessing genetic diversity and structure of garlic collections is the first step towards an efficient management and conservation of accessions in genebanks, as well as to advance future genetic studies and improvement of garlic worldwide.

Development of Simple Sequence Repeats (SSR) markers in Setaria italica (Poaceae) and cross-amplification in related species.

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Lin, Heng-Sheng; Chiang, Chih-Yun; Chang, Song-Bin; Kuoh, Chang-Sheng

2011-01-01

Foxtail millet is one of the world's oldest cultivated crops. It has been adopted as a model organism for providing a deeper understanding of plant biology. In this study, 45 simple sequence repeats (SSR) markers of Setaria italica were developed. These markers showing polymorphism were screened in 223 samples from 12 foxtail millet populations around Taiwan. The most common dinucleotide and trinucleotide repeat motifs are AC/TG (84.21%) and CAT (46.15%). The average number of alleles (N(a)), the average heterozygosities observed (H(o)) and expected (H(e)) are 3.73, 0.714, 0.587, respectively. In addition, 24 SSR markers had shown transferability to six related Poaceae species. These new markers provide tools for examining genetic relatedness among foxtail millet populations and other related species. It is suitable for germplasm management and protection in Poaceae.

Rapid in silico cloning of genes using expressed sequence tags (ESTs).

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Gill, R W; Sanseau, P

2000-01-01

Expressed sequence tags (ESTs) are short single-pass DNA sequences obtained from either end of cDNA clones. These ESTs are derived from a vast number of cDNA libraries obtained from different species. Human ESTs are the bulk of the data and have been widely used to identify new members of gene families, as markers on the human chromosomes, to discover polymorphism sites and to compare expression patterns in different tissues or pathologies states. Information strategies have been devised to query EST databases. Since most of the analysis is performed with a computer, the term "in silico" strategy has been coined. In this chapter we will review the current status of EST databases, the pros and cons of EST-type data and describe possible strategies to retrieve meaningful information.

The CRF₁ receptor antagonist SSR125543 prevents stress-induced long-lasting sleep disturbances in a mouse model of PTSD: comparison with paroxetine and d-cycloserine.

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Philbert, Julie; Beeské, Sandra; Belzung, Catherine; Griebel, Guy

2015-02-15

The selective CRF₁ (corticotropin releasing factor type 1) receptor antagonist SSR125543 has been previously shown to attenuate the long-term behavioral and electrophysiological effects produced by traumatic stress exposure in mice. Sleep disturbances are one of the most commonly reported symptoms by people with post-traumatic stress disorder (PTSD). The present study aims at investigating whether SSR125543 (10 mg/kg/day/i.p. for 2 weeks) is able to attenuate sleep/wakefulness impairment induced by traumatic stress exposure in a model of PTSD in mice using electroencephalographic (EEG) analysis. Effects of SSR125543 were compared to those of the 5-HT reuptake inhibitor, paroxetine (10 mg/kg/day/i.p.), and the partial N-methyl-d-aspartate (NMDA) receptor agonist, d-cycloserine (10 mg/kg/day/i.p.), two compounds which have demonstrated clinical efficacy against PTSD. Baseline EEG recording was performed in the home cage for 6h prior to the application of two electric foot-shocks of 1.5 mA. Drugs were administered from day 1 post-stress to the day preceding the second EEG recording session, performed 14 days later. Results showed that at day 14 post-stress, shocked mice displayed sleep fragmentation as shown by an increase in the occurrence of both non-rapid eye movement (NREM) sleep and wakefulness bouts. The duration of wakefulness, NREM and REM sleep were not significantly affected. The stress-induced effects were prevented by repeated administration of SSR125543, paroxetine and D-cycloserine. These findings confirm further that the CRF₁ receptor antagonist SSR125543 is able to attenuate the deleterious effects of traumatic stress exposure. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of Gene-Based SSR Markers in Rice Bean (Vigna umbellata L. Based on Transcriptome Data.

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Honglin Chen

Full Text Available Rice bean (Vigna umbellata (Thunb. Ohwi & Ohashi is a warm season annual legume mainly grown in East Asia. Only scarce genomic resources are currently available for this legume crop species and no simple sequence repeat (SSR markers have been specifically developed for rice bean yet. In this study, approximately 26 million high quality cDNA sequence reads were obtained from rice bean using Illumina paired-end sequencing technology and assembled into 71,929 unigenes with an average length of 986 bp. Of these unigenes, 38,840 (33.2% showed significant similarity to proteins in the NCBI non-redundant protein and nucleotide sequence databases. Furthermore, 30,170 (76.3% could be classified into gene ontology categories, 25,451 (64.4% into Swiss-Prot categories and 21,982 (55.6% into KOG database categories (E-value < 1.0E-5. A total of 9,301 (23.5% were mapped onto 118 pathways using the Kyoto Encyclopedia of Genes and Genome (KEGG pathway database. A total of 3,011 genic SSRs were identified as potential molecular markers. AG/CT (30.3%, AAG/CTT (8.1% and AGAA/TTCT (20.0% are the three main repeat motifs. A total of 300 SSR loci were randomly selected for validation by using PCR amplification. Of these loci, 23 primer pairs were polymorphic among 32 rice bean accessions. A UPGMA dendrogram revealed three major clusters among 32 rice bean accessions. The large number of SSR-containing sequences and genic SSRs in this study will be valuable for the construction of high-resolution genetic linkage maps, association or comparative mapping and genetic analyses of various Vigna species.

Molecular characterization of barley (Hordeum vulgare L. accessions of the Serbian GeneBank by SSR fingerprinting

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Šurlan-Momirović Gordana

2013-01-01

Full Text Available Molecular diversity of 145 barley (Hordeum vulgare subsp. vulgare L. accessions from the Serbian GenBank was assessed by single sequence repeats (SSR markers. A set of 15 SSRs, covering all chromosomes of the diploid barley genome with 2-3 SSR markers per chromosome, with a range of 4-18 alleles per locus were used. In total, 15 loci and 119 alleles were detected, with an average of 7.93 alleles per locus. The Polymorphic information content value ranged from 0.220 to 0.782 with a mean value of 0.534. Regarding the growth habit and row type groups, gene diversity was comparatively higher for the spring (0.616 and six-rowed accessions (0.616 than for the winter and two- rowed accessions (0.322 and 0.478, respectively. Analysis of molecular variance showed that all sources of variation were significant (P < 0.01, but the between-group component was predominant (76.85% for growth habit and 89.45% for row type. Unweighted Pair Group Method with Arithmetic Mean (UPGMA cluster analysis based on the shared allele distance (DSA matrix estimated on the SSR data assigned the genotypes into two clusters - the first smaller consisting of the six 6-rowed spring cultivars and the second comprising six subclusters. Genotype MBR1012 was separated from all other genotypes that constitute UPGMA tree. The associations of genotypes belonging to different growth habit and row type groups were assessed using Principal Coordinate Analysis revealing separation of winter growth habit group from facultative one. The use of the STRUCTURE clustering algorithm allowed the identification of 2 subpopulations of genotypes. [Projekat Ministarstva nauke Republike Srbije, br. TR31092

[An evaluation of the economic loss from intestinal helminthiases in the Uzbek SSR].

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Abdiev, T A; Zubitskaia, M A; Kovalenko, A F; Fuzaĭlov, Iu M; Baratov, R D; Ziganshina, N Kh; Isaeva, Kh B; Borukhov, S M; Priezzhaeva, N G; Musaeva, G A

1990-01-01

Calculations of economic loss costs due to procedures for helminth detection and the out-patient treatment of recognized cases of enterobiasis, hymenolepiasis, taeniasis, ascariasis, trichocephaliasis in the Uzbek SSR in 1985 were made as were the costs of inpatient treatment in the specialized clinics in 1986 with account for the loss due to the related decrease in the national output and payments for disability. Their total turned to be about 1.8 million rubles.

Analysis of genetic diversity of Sclerotinia sclerotiorum from eggplant by mycelial compatibility, random amplification of polymorphic DNA (RAPD and simple sequence repeat (SSR analyses

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Fatih Mehmet Tok

2016-09-01

Full Text Available The genetic diversity and pathogenicity/virulence among 60 eggplant Sclerotinia sclerotiorum isolates collected from six different geographic regions of Turkey were analysed using mycelial compatibility groupings (MCGs, random amplified polymorphic DNA (RAPD and simple sequence repeat (SSR polymorphism. By MCG tests, the isolates were classified into 22 groups. Out of 22 MCGs, 36% were represented each by a single isolate. The isolates showed great variability for virulence regardless of MCG and geographic origin. Based on the results of RAPD and SSR analyses, 60 S. sclerotiorum isolates representing 22 MCGs were grouped in 2 and 3 distinct clusters, respectively. Analyses using RAPD and SSR markers illustrated that cluster groupings or genetic distance of S. sclerotiorum populations from eggplant were not distinctly relative to the MCG, geographical origin and virulence diversity. The patterns obtained revealed a high heterogeneity of genetic composition and suggested the occurrence of clonal and sexual reproduction of S. sclerotiorum on eggplant in the areas surveyed.

Phylogeny and sequence variability of the Sarcocystis singaporensis Zaman and Colley, (1975) 1976 ssrDNA

Czech Academy of Sciences Publication Activity Database

Šlapeta, Jan Roger; Kyselová, Iveta; Richardson, A. O.; Modrý, David; Lukeš, Julius

2002-01-01

Roč. 88, č. 9 (2002), s. 810-815 ISSN 0932-0113 R&D Projects: GA ČR GA524/00/P015; GA AV ČR KSK6005114 Institutional research plan: CEZ:AV0Z6022909 Keywords : Sarcocystis * phylogeny * ssrDNA Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.046, year: 2002

Molecular Assortment of Lens Species with Different Adaptations to Drought Conditions Using SSR Markers

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Singh, Dharmendra; Singh, Chandan Kumar; Tomar, Ram Sewak Singh; Taunk, Jyoti; Singh, Ranjeet; Maurya, Sadhana; Chaturvedi, Ashish Kumar; Pal, Madan; Singh, Rajendra; Dubey, Sarawan Kumar

2016-01-01

The success of drought tolerance breeding programs can be enhanced through molecular assortment of germplasm. This study was designed to characterize molecular diversity within and between Lens species with different adaptations to drought stress conditions using SSR markers. Drought stress was applied at seedling stage to study the effects on morpho-physiological traits under controlled condition, where tolerant cultivars and wilds showed 12.8–27.6% and 9.5–23.2% reduction in seed yield per plant respectively. When juxtaposed to field conditions, the tolerant cultivars (PDL-1 and PDL-2) and wild (ILWL-314 and ILWL-436) accessions showed 10.5–26.5% and 7.5%–15.6% reduction in seed yield per plant, respectively under rain-fed conditions. The reductions in seed yield in the two tolerant cultivars and wilds under severe drought condition were 48–49% and 30.5–45.3% respectively. A set of 258 alleles were identified among 278 genotypes using 35 SSR markers. Genetic diversity and polymorphism information contents varied between 0.321–0.854 and 0.299–0.836, with mean value of 0.682 and 0.643, respectively. All the genotypes were clustered into 11 groups based on SSR markers. Tolerant genotypes were grouped in cluster 6 while sensitive ones were mainly grouped into cluster 7. Wild accessions were separated from cultivars on the basis of both population structure and cluster analysis. Cluster analysis has further grouped the wild accessions on the basis of species and sub-species into 5 clusters. Physiological and morphological characters under drought stress were significantly (P = 0.05) different among microsatellite clusters. These findings suggest that drought adaptation is variable among wild and cultivated genotypes. Also, genotypes from contrasting clusters can be selected for hybridization which could help in evolution of better segregants for improving drought tolerance in lentil. PMID:26808306

Development of Simple Sequence Repeats (SSR Markers in Setaria italica (Poaceae and Cross-Amplification in Related Species

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Chih-Yun Chiang

2011-11-01

Full Text Available Foxtail millet is one of the world’s oldest cultivated crops. It has been adopted as a model organism for providing a deeper understanding of plant biology. In this study, 45 simple sequence repeats (SSR markers of Setaria italica were developed. These markers showing polymorphism were screened in 223 samples from 12 foxtail millet populations around Taiwan. The most common dinucleotide and trinucleotide repeat motifs are AC/TG (84.21% and CAT (46.15%. The average number of alleles (Na, the average heterozygosities observed (Ho and expected (He are 3.73, 0.714, 0.587, respectively. In addition, 24 SSR markers had shown transferability to six related Poaceae species. These new markers provide tools for examining genetic relatedness among foxtail millet populations and other related species. It is suitable for germplasm management and protection in Poaceae.

Study the Stability of SSR Repeats of pEA29 Plasmid of the Casual Agent of Fire Blight

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S. Baghaee Ravari

2016-02-01

Full Text Available Introduction Fire blight disease causes by Erwinia amylovora infects a wide variety of rosaceous plants. It was first recorded from pear trees in Karaj in year 1990. After that it was observed in many pear and apple orchards of the country. E. amylovora isolates differed slightly in virulence, symptoms and host range which ca be related to different plasmid content. The presence of an universal plasmid, pEA29, has been observed in majority of E. amylovora strains. Short-sequence DNA repeat with eight nt were repeated 3 to 15 times in the PstI fragment of the pEA29 plasmid. Here, the stability of SSR units and efficiency of this method to categorize strains was checked. For this reseaon two methods including amplification and cloning of whole and part of PstI fragment was done and the sequences were compared to eachother. In addition stability was evaluated based on three treatments including long time propagation, keeping strains in cold situation and re-isolation of infected tissues. Materials and Methods In this study 20 strains were purchased from the Iranian Plant Protection Research Institute. Their typical phenotypic tests were examined for all strains. All of then were checked with lateral flow immune chromatography in different serial dilutions. The pathogenicity were aassayed using complete fruit. Direct PCR with A/B primers and nested PCR with AJ75/AJ76 were applied for studied strains. Ten representative strains were selected snf part of PstI fragment amplified using RS1/RS2 primers. The PCR products were purified by QIAquick PCR purification kit (Qiagen, USA, cloned in pGEM-T and were sequenced (Macrogen Inc., Korea. Five of 10 were chosen for stability tests including long time propagation and sub culturing each two week for three months, keeping strains in refrigerator for three months and re-isolation of infected tissues. Results and Discussion In phenotypic tests all studies strains were facultative anaerobic growth, oxidase

Development of ESTs from chickpea roots and their use in diversity analysis of the Cicer genus

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Eshwar K

2005-08-01

Full Text Available Abstract Background Chickpea is a major crop in many drier regions of the world where it is an important protein-rich food and an increasingly valuable traded commodity. The wild annual Cicer species are known to possess unique sources of resistance to pests and diseases, and tolerance to environmental stresses. However, there has been limited utilization of these wild species by chickpea breeding programs due to interspecific crossing barriers and deleterious linkage drag. Molecular genetic diversity analysis may help predict which accessions are most likely to produce fertile progeny when crossed with chickpea cultivars. While, trait-markers may provide an effective tool for breaking linkage drag. Although SSR markers are the assay of choice for marker-assisted selection of specific traits in conventional breeding populations, they may not provide reliable estimates of interspecific diversity, and may lose selective power in backcross programs based on interspecific introgressions. Thus, we have pursued the development of gene-based markers to resolve these problems and to provide candidate gene markers for QTL mapping of important agronomic traits. Results An EST library was constructed after subtractive suppressive hybridization (SSH of root tissue from two very closely related chickpea genotypes (Cicer arietinum. A total of 106 EST-based markers were designed from 477 sequences with functional annotations and these were tested on C. arietinum. Forty-four EST markers were polymorphic when screened across nine Cicer species (including the cultigen. Parsimony and PCoA analysis of the resultant EST-marker dataset indicated that most accessions cluster in accordance with the previously defined classification of primary (C. arietinum, C. echinospermum and C. reticulatum, secondary (C. pinnatifidum, C. bijugum and C. judaicum, and tertiary (C. yamashitae, C. chrossanicum and C. cuneatum gene-pools. A large proportion of EST alleles (45% were only

Language Policy, Tacit Knowledge, and Institutional Learning: The Case of the Swiss Public Service Broadcaster SRG SSR

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Perrin, Daniel

2011-01-01

"Promoting public understanding" is what the programming mandate asks the Swiss public broadcasting company SRG SSR to do. From a sociolinguistic perspective, this means linking speech communities with other speech communities, both between and within the German-, French-, Italian-, and Romansh-speaking parts of Switzerland. In the…

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers

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Saba Jasim Aljumaili

2018-01-01

Full Text Available Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak with 3 released varieties as a control using the 32 simple sequence repeat (SSR markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon’s information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He of 0.60 and mean Nei’s gene diversity index of 0.36. The dendrogram based on UPGMA and Nei’s genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816 from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers.

Science.gov (United States)

Jasim Aljumaili, Saba; Rafii, M Y; Latif, M A; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous

2018-01-01

Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index ( I ) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity ( H e ) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.

Genetic Diversity of Aromatic Rice Germplasm Revealed By SSR Markers

Science.gov (United States)

Jasim Aljumaili, Saba; Sakimin, Siti Zaharah; Arolu, Ibrahim Wasiu; Miah, Gous

2018-01-01

Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development. PMID:29736396

Screening of the White Button Mushroom (Agaricusbisporus Homokaryons and Producing New Hybrid Strain by SSR Markers

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marzieh nourashrafeddin

2018-02-01

Full Text Available Introduction: Edible white button mushroom (Agaricusbisporus is the most common edible mushroom in Iran and the world. The yield of this mushroom is less than the average of yield in the world because of strain degeneration and using strains with low yield. Most of the current hybrids are either identical or very similar to the first hybrids. Ongoing breeding programs are exploiting the variability in Agaricus germplasm to produce new varieties with better traits including higher yield and resistance to biotic and abiotic stresses. One of the breeding programs is F1 production from parental homokaryons crossing. These homokaryonsis were isolated among germinated basidiospores on the culture media. During the last decades, various molecular markers based on nucleic acid polymorphisms (such as Restriction Fragment Length Polymorphism, Random Amplification of Polymorphic DNA, Amplified fragment of Length Polymorphism, Inter Simple Sequence Repeat, Simple Sequence Repeat markers have been used to differentiate homokaryons and heterokaryons. Microsatellites consist of short tandem repeat motifs distributed throughout the genome. Microsatellites are usually highly polymorphic due to a high degree of variation in the number of repeats among individuals. Microsatellite markers are multiallelic and co-dominant and thus tend to be more informative than other marker systems. Microsatellite markers have been widely developed in animals and plants and more recently in fungal species. The presence of microsatellites in the genome of A. bisporus was previously reported. Materials and Methods: In this research, 160 germinated basidiospores were collected from commercially cultivated strain A15 and they were grown on compost extract agar (CEA. The mycelial growth rate of these160 isolates was evaluated at 25°C on CEA medium. 18 isolates with slow growing rate were selected from 160 isolates. In the next step, co-dominant SSR markers were used to homokaryons

Comparative mapping in intraspecific populations uncovers a high degree of macrosynteny between A- and B-genome diploid species of peanut

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Guo Yufang

2012-11-01

Full Text Available Abstract Background Cultivated peanut or groundnut (Arachis hypogaea L. is an important oilseed crop with an allotetraploid genome (AABB, 2n = 4x = 40. Both the low level of genetic variation within the cultivated gene pool and its polyploid nature limit the utilization of molecular markers to explore genome structure and facilitate genetic improvement. Nevertheless, a wealth of genetic diversity exists in diploid Arachis species (2n = 2x = 20, which represent a valuable gene pool for cultivated peanut improvement. Interspecific populations have been used widely for genetic mapping in diploid species of Arachis. However, an intraspecific mapping strategy was essential to detect chromosomal rearrangements among species that could be obscured by mapping in interspecific populations. To develop intraspecific reference linkage maps and gain insights into karyotypic evolution within the genus, we comparatively mapped the A- and B-genome diploid species using intraspecific F2 populations. Exploring genome organization among diploid peanut species by comparative mapping will enhance our understanding of the cultivated tetraploid peanut genome. Moreover, new sources of molecular markers that are highly transferable between species and developed from expressed genes will be required to construct saturated genetic maps for peanut. Results A total of 2,138 EST-SSR (expressed sequence tag-simple sequence repeat markers were developed by mining a tetraploid peanut EST assembly including 101,132 unigenes (37,916 contigs and 63,216 singletons derived from 70,771 long-read (Sanger and 270,957 short-read (454 sequences. A set of 97 SSR markers were also developed by mining 9,517 genomic survey sequences of Arachis. An SSR-based intraspecific linkage map was constructed using an F2 population derived from a cross between K 9484 (PI 298639 and GKBSPSc 30081 (PI 468327 in the B-genome species A. batizocoi. A high degree of macrosynteny was observed

Genomic validation of PB 260 clone of rubber (Hevea brasiliensis) at Cikumpay Plantation by SSR marker

Science.gov (United States)

Royani, J. I.; Safarrida, A.; Rachmawati, I.; Khairiyah, H.; Mustika, I. P.; Suyono, A.; Rudiyana, Y.; Kubil; Nurjaya; Arianto, A.

2017-05-01

Rubber from Hevea brasiliensis is the only commercial natural rubber in the world. Propagation of rubber trees usually done by grafting and seed germination. BPPT had been producing rubber tree by in vitro technique with embryo somatic methods. Validation of mother plant for in vitro propagation is important to compare between mother plant and propagated plants. The aim for this research was to validation of PB 260 clone that planted at Cikumpay Plantation by SSR marker. Sampling of 10 rubber leaves were done at Cikumpay Plantation based on GPS position from the area of PB 260 clone. Rubber leaves were isolated with CTAB modification method to obtained DNA. Four of SSR primers from rubber, i.e.: hmac 4, hmac 5, hmct 1, and hmct 5, were used as primers to amplification of rubber DNA. The result showed that no band that different from 10 rubber of PB 260 clone at Cikumpay Plantation. This research will continue to compare genomic validation between mother plant and propagated plants that had been produced from BPPT.

Comparative Genomics Analyses Reveal Extensive Chromosome Colinearity and Novel Quantitative Trait Loci in Eucalyptus

Science.gov (United States)

Weng, Qijie; Li, Mei; Yu, Xiaoli; Guo, Yong; Wang, Yu; Zhang, Xiaohong; Gan, Siming

2015-01-01

Dense genetic maps, along with quantitative trait loci (QTLs) detected on such maps, are powerful tools for genomics and molecular breeding studies. In the important woody genus Eucalyptus, the recent release of E. grandis genome sequence allows for sequence-based genomic comparison and searching for positional candidate genes within QTL regions. Here, dense genetic maps were constructed for E. urophylla and E. tereticornis using genomic simple sequence repeats (SSR), expressed sequence tag (EST) derived SSR, EST-derived cleaved amplified polymorphic sequence (EST-CAPS), and diversity arrays technology (DArT) markers. The E. urophylla and E. tereticornis maps comprised 700 and 585 markers across 11 linkage groups, totaling at 1,208.2 and 1,241.4 cM in length, respectively. Extensive synteny and colinearity were observed as compared to three earlier DArT-based eucalypt maps (two maps with E. grandis × E. urophylla and one map of E. globulus) and with the E. grandis genome sequence. Fifty-three QTLs for growth (10–56 months of age) and wood density (56 months) were identified in 22 discrete regions on both maps, in which only one colocalizaiton was found between growth and wood density. Novel QTLs were revealed as compared with those previously detected on DArT-based maps for similar ages in Eucalyptus. Eleven to 585 positional candidate genes were obained for a 56-month-old QTL through aligning QTL confidence interval with the E. grandis genome. These results will assist in comparative genomics studies, targeted gene characterization, and marker-assisted selection in Eucalyptus and the related taxa. PMID:26695430

Comparative Genomics Analyses Reveal Extensive Chromosome Colinearity and Novel Quantitative Trait Loci in Eucalyptus.

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Fagen Li

Full Text Available Dense genetic maps, along with quantitative trait loci (QTLs detected on such maps, are powerful tools for genomics and molecular breeding studies. In the important woody genus Eucalyptus, the recent release of E. grandis genome sequence allows for sequence-based genomic comparison and searching for positional candidate genes within QTL regions. Here, dense genetic maps were constructed for E. urophylla and E. tereticornis using genomic simple sequence repeats (SSR, expressed sequence tag (EST derived SSR, EST-derived cleaved amplified polymorphic sequence (EST-CAPS, and diversity arrays technology (DArT markers. The E. urophylla and E. tereticornis maps comprised 700 and 585 markers across 11 linkage groups, totaling at 1,208.2 and 1,241.4 cM in length, respectively. Extensive synteny and colinearity were observed as compared to three earlier DArT-based eucalypt maps (two maps with E. grandis × E. urophylla and one map of E. globulus and with the E. grandis genome sequence. Fifty-three QTLs for growth (10-56 months of age and wood density (56 months were identified in 22 discrete regions on both maps, in which only one colocalizaiton was found between growth and wood density. Novel QTLs were revealed as compared with those previously detected on DArT-based maps for similar ages in Eucalyptus. Eleven to 585 positional candidate genes were obained for a 56-month-old QTL through aligning QTL confidence interval with the E. grandis genome. These results will assist in comparative genomics studies, targeted gene characterization, and marker-assisted selection in Eucalyptus and the related taxa.

SSR allelic variation of rice variety Hangxiangnuo bred by space mutation

International Nuclear Information System (INIS)

Yang Tifeng; Liu Chuanguang; Pan Dajian; Fan Zhilan; Li Chen; Chen Jianyou; Liu Bin; Jiang Yijun; Gao Yun; Zhou Hanqin

2011-01-01

Hangxiangnuo, an indica fragrant glutinous rice mutant, was induced by space environment. Comparing with its wild type Nanfengnuo, the yield and blast resistance of Hangxiangnuo are improved significantly and the grain shape became slender and with fragrance. To understand the mechanisms of space mutation and identify the changes at molecular level associated with phenotypic variations, SSR allelic variation analysis were performed on Hangxiangnuo and Nanfengnuo in this study. The results showed that 45 loci were polymorphic among the 156 SSR loci tested throughout the genome, the frequency of variation was 28.85%. Among the polymorphic loci, 42 loci only showed variations in the molecular weight of the amplified bands, only on locus increased the number of amplification bands in Hangxiangnuo and two loci were differed by heterozygous loci (with two amplification bands at one locus) detected in Nanfengnuo and homozygous loci in Hangxiangnuo. It suggests that the change of some loci in mutants was due to the normal segregation and recombination of heterozygous loci of the wild type. The variation frequencies among different chromosomes were quite different, with the highest one at 50.00% detected on chromosomes 7, 8 and 12, and the lowest at 6.25% on chromosome 6. The polymorphic loci were clustered on chromosomes throughout the genome indicating that large DNA segments mutation is one of the major variation patterns induced by space environment. Some of reported QTLs involved in grain shape, yield, fragrance and blast resistance were found to be located exactly in the mutated regions. Therefore, further study is needed to confirm that these QTLs are responsible for the trait variations. (authors)

Characterization of functional SSR markers in Prosopis alba and their transferability across Prosopis species

OpenAIRE

María F. Pomponio; Cintia Acuña; Vivien Pentreath; Diego L. Lauenstein; Susana M. Poltri; Susana Torales

2015-01-01

Aim of study: The aim of the study was to characterize functional microsatellite markers in Prosopis alba and examine the transferability to species from the Prosopis genus. Area of the study: samples were obtained from natural populations of Argentina. Material and Methods: Eleven SSR functional markers related to stress and metabolism were amplified in a sample of 152 genotypes from P.alba, P. denudans, P. hassleriP. chilensis, P. flexuosa, and interspecific hybrids. Main res...

Analysis of simple sequence repeats in rice bean (Vigna umbellata using an SSR-enriched library

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Lixia Wang

2016-02-01

Full Text Available Rice bean (Vigna umbellata Thunb., a warm-season annual legume, is grown in Asia mainly for dried grain or fodder and plays an important role in human and animal nutrition because the grains are rich in protein and some essential fatty acids and minerals. With the aim of expediting the genetic improvement of rice bean, we initiated a project to develop genomic resources and tools for molecular breeding in this little-known but important crop. Here we report the construction of an SSR-enriched genomic library from DNA extracted from pooled young leaf tissues of 22 rice bean genotypes and developing SSR markers. In 433,562 reads generated by a Roche 454 GS-FLX sequencer, we identified 261,458 SSRs, of which 48.8% were of compound form. Dinucleotide repeats were predominant with an absolute proportion of 81.6%, followed by trinucleotides (17.8%. Other types together accounted for 0.6%. The motif AC/GT accounted for 77.7% of the total, followed by AAG/CTT (14.3%, and all others accounted for 12.0%. Among the flanking sequences, 2928 matched putative genes or gene models in the protein database of Arabidopsis thaliana, corresponding with 608 non-redundant Gene Ontology terms. Of these sequences, 11.2% were involved in cellular components, 24.2% were involved molecular functions, and 64.6% were associated with biological processes. Based on homolog analysis, 1595 flanking sequences were similar to mung bean and 500 to common bean genomic sequences. Comparative mapping was conducted using 350 sequences homologous to both mung bean and common bean sequences. Finally, a set of primer pairs were designed, and a validation test showed that 58 of 220 new primers can be used in rice bean and 53 can be transferred to mung bean. However, only 11 were polymorphic when tested on 32 rice bean varieties. We propose that this study lays the groundwork for developing novel SSR markers and will enhance the mapping of qualitative and quantitative traits and marker

78 FR 9987 - Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations...

Science.gov (United States)

2013-02-12

... SOCIAL SECURITY ADMINISTRATION [Docket No. SSA-2012-0071] Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations of Unfairness, Prejudice, Partiality, Bias, Misconduct, or Discrimination by Administrative Law Judges (ALJs); Correction AGENCY: Social Security...

78 FR 22361 - Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations...

Science.gov (United States)

2013-04-15

... SOCIAL SECURITY ADMINISTRATION [Docket No. SSA-2012-0071] Social Security Ruling, SSR 13-1p; Titles II and XVI: Agency Processes for Addressing Allegations of Unfairness, Prejudice, Partiality, Bias, Misconduct, or Discrimination by Administrative Law Judges (ALJs); Correction AGENCY: Social Security...

Genetic variability assessment in the genus Passiflora by SSR markers

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Claudia Lougon Paiva

2014-09-01

Full Text Available The genus Passiflora encompasses many species that are endemic to the Brazilian territory, including some with economic value. Studies on genetic diversity in this genus are fundamental because they allow understanding genetic variability and distance. The present study aimed to determine the genetic variability and distances among 10 species of the genus Passiflora by using microsatellite markers (Simple Sequence Repeat, SSR. Twenty-eight heterologous microsatellite markers were tested, but only 12 were used in the diversity analysis because they amplified in at least 80% of the species. A clear separation was observed among the subgenuses studied, as well as wide variation among the accessions of Passiflora. This knowledge enables breeders to explore diversity and transfer favorable alleles found in wild species.

Fluorescence- and capillary electrophoresis (CE)-based SSR DNA fingerprinting and a molecular identity database for the Louisiana sugarcane industry

Science.gov (United States)

A database of Louisiana sugarcane molecular identity has been constructed and is being updated annually using FAM or HEX or NED fluorescence- and capillary electrophoresis (CE)-based microsatellite (SSR) fingerprinting information. The fingerprints are PCR-amplified from leaf DNA samples of current ...

Association mapping to discover significant marker-trait associations for resistance against fusarium wilt variant 2 in pigeonpea [Cajanus cajan (L.) Millspaugh] using SSR markers.

Science.gov (United States)

Patil, Prakash G; Dubey, Jyotirmay; Bohra, Abhishek; Mishra, R K; Saabale, P R; Das, Alok; Rathore, Meenal; Singh, N P

2017-08-01

Pigeonpea production is severely constrained by wilt disease caused by Fusarium udum. In the current study, we discover the putative genomic regions that control resistance response to variant 2 of fusarium wilt using association mapping approach. The association panel comprised of 89 diverse pigeonpea genotypes including seven varieties, three landraces and 79 germplasm lines. The panel was screened rigorously for 3 consecutive years (2013-14, 2014-15 and 2015-2016) against variant 2 in a wilt-sick field. A total of 65 pigeonpea specific hypervariable SSR markers (HASSRs) were screened representing seven linkage groups and 29 scaffolds of the pigeonpea genome. A total of 181 alleles were detected, with average values of gene diversity and polymorphism information content (PIC) of 0.55 and 0.47, respectively. Further analysis using model based (STRUCTURE) and distance based (clustering) approaches separated the entire pigeonpea collection into two distinct subgroups (K = 2). The marker trait associations (MTAs) were established based on three-year wilt incidence data and SSR dataset using a unified mixed linear model. Consequently, six SSR markers were identified, which were significantly associated with wilt resistance and explained up to 6% phenotypic variance (PV) across the years. Among these SSRs, HASSR18 was found to be the most stable and significant, accounting for 5-6% PV across the years. To the best of our knowledge, this is the first report of identification of favourable alleles for resistance to variant 2 of Fusarium udum in pigeonpea using association mapping. The SSR markers identified here will greatly facilitate marker assisted resistance breeding against fusarium wilt in pigeonpea.

AcEST(EST sequences of Adiantum capillus-veneris and their annotation) - AcEST | LSDB Archive [Life Science Database Archive metadata

Lifescience Database Archive (English)

Full Text Available List Contact us AcEST AcEST(EST sequences of Adiantum capillus-veneris and their annotation) Data detail Dat...a name AcEST(EST sequences of Adiantum capillus-veneris and their annotation) DOI 10.18908/lsdba.nbdc00839-0...01 Description of data contents EST sequence of Adiantum capillus-veneris and its annotation (clone ID, libr...le search URL http://togodb.biosciencedbc.jp/togodb/view/archive_acest#en Data acquisition method Capillary ...ainst UniProtKB/Swiss-Prot and UniProtKB/TrEMBL databases) Number of data entries Adiantum capillus-veneris

Fostering eGovernment as State Social Responsibility (SSR: Case Study of an Australian City Council

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Sinara Rao Karna

2012-12-01

Full Text Available           Democracies around the world now face Citizen-apathy. This is a concern now more than ever faced by countries around the globe. eGovernment is undoubtedly a platform to deliberate and enable citizens regain confidence and faith in democratic  processes. Citizens now seek Verifiable, Open, Transparent, Empathetic, Responsive and Sensitive Electronic Democracy and Government (VOTERS EDG, Karna, 2012. Similar to corporate world, there are voices stressing on govenments for the need to understand the stakeholders, their involvement, relationships and responsibilities of a state in eGovernance. Citizens everywhere now demand Verifiable, Open, Transparent, Empathetic, Responsive and Sensitive Electronically Democratic Government as a State Social Responsibity (SSR. Peoples movements and outbursts against authorities with the help of Word of Mouse (Karna, 2012 have established that transparent and open governance is the need of the hour. This paper presents findings of the study conducted in an Australian City Council for preparing the city council for ‘City e-readiness’ to initiate e-Government activities. We propose the idea of ‘Centrality of Citizens’ in context of eGovernment. We further build upon the original concept of deeming eGovernment as ‘State Social Responsibility’ (SSR (Karna, 2010, by governments at all levels.  

Identification of QTLs Associated with Callogenesis and Embryogenesis in Oil Palm Using Genetic Linkage Maps Improved with SSR Markers.

NARCIS (Netherlands)

Ting, N.C.; Jansen, J.; Nagappan, J.; Ishak, Z.; Chin, C.W.; Tan, S.G.; Cheah, S.C.; Singh, R.

2013-01-01

Clonal reproduction of oil palm by means of tissue culture is a very inefficient process. Tissue culturability is known to be genotype dependent with some genotypes being more amenable to tissue culture than others. In this study, genetic linkage maps enriched with simple sequence repeat (SSR)

Supplementary data: Eucalyptus microsatellites mined in silico ...

Indian Academy of Sciences (India)

Supplementary data: Eucalyptus microsatellites mined in silico: survey and evaluation. R. Yasodha, R. Sumathi, P. Chezhian, S. Kavitha and M. Ghosh. J. Genet. 87, XX-XX. Tm. CT. 2222. NA. 60 125. 192. Table 1. List of EST-SSR primers developed for E. globulus. No. of. Tm Product. Acc. no. SSR repeats. Forward primer.

Genome survey of pistachio (Pistacia vera L.) by next generation sequencing: Development of novel SSR markers and genetic diversity in Pistacia species.

Science.gov (United States)

Ziya Motalebipour, Elmira; Kafkas, Salih; Khodaeiaminjan, Mortaza; Çoban, Nergiz; Gözel, Hatice

2016-12-07

Pistachio (Pistacia vera L.) is one of the most important nut crops in the world. There are about 11 wild species in the genus Pistacia, and they have importance as rootstock seed sources for cultivated P. vera and forest trees. Published information on the pistachio genome is limited. Therefore, a genome survey is necessary to obtain knowledge on the genome structure of pistachio by next generation sequencing. Simple sequence repeat (SSR) markers are useful tools for germplasm characterization, genetic diversity analysis, and genetic linkage mapping, and may help to elucidate genetic relationships among pistachio cultivars and species. To explore the genome structure of pistachio, a genome survey was performed using the Illumina platform at approximately 40× coverage depth in the P. vera cv. Siirt. The K-mer analysis indicated that pistachio has a genome that is about 600 Mb in size and is highly heterozygous. The assembly of 26.77 Gb Illumina data produced 27,069 scaffolds at N50 = 3.4 kb with a total of 513.5 Mb. A total of 59,280 SSR motifs were detected with a frequency of 8.67 kb. A total of 206 SSRs were used to characterize 24 P. vera cultivars and 20 wild Pistacia genotypes (four genotypes from each five wild Pistacia species) belonging to P. atlantica, P. integerrima, P. chinenesis, P. terebinthus, and P. lentiscus genotypes. Overall 135 SSR loci amplified in all 44 cultivars and genotypes, 41 were polymorphic in six Pistacia species. The novel SSR loci developed from cultivated pistachio were highly transferable to wild Pistacia species. The results from a genome survey of pistachio suggest that the genome size of pistachio is about 600 Mb with a high heterozygosity rate. This information will help to design whole genome sequencing strategies for pistachio. The newly developed novel polymorphic SSRs in this study may help germplasm characterization, genetic diversity, and genetic linkage mapping studies in the genus Pistacia.

The assessment of genetic diversity between and within brassica species and their wild relative (eruca sativa) using ssr markers

International Nuclear Information System (INIS)

Kanwal, M.; Farhatullah, A.; Iqbal, S.; Fayyaz, L.; Rabbani, M.A.

2014-01-01

Microsatellites markers were tested for their ability to distinguish genomic distribution of the Brassica species of the U Triangle and E. sativa. The objectives of the present study were to investigate the genetic diversity of six Brassica species from U-Triangle (representing three genomes, A, B, C) and one from genus Eruca and to identify promising sources of genetic variation for breeding purposes. A total of 54 SSR markers were analyzed in order to detect variation between and within the selected genomes. Three primer pairs depicted the greatest genetic diversity showing 97% polymorphism between Brassica and Eruca genomes (2.55 alleles per locus). Polymorphic Information Content (PIC) values ranged from 0.40 (SSR primer Na14-DO7) to 0.79 (NA10-G09). For comparison within Brassica genomes and Eruca, all the genomes were grouped in three modules i.e., ABE, ACE and BCE (Fig. 1). The tetraploid originating from their parental diploids along-with Eruca was considered in the same module. For the estimation of relatedness within and among genomes, dice coefficients were computed as a measure of genetic similarity matrix. On the basis of genetic distances, dendrogram was constructed through cluster analysis. Two major clusters at coefficient of similarity level (0.47) were observed. One cluster comprised of all Brassica genomes and their accessions, while another consisting of all accessions of Eruca genome. The cluster containing Brassica genomes was further subdivided into four sub-groups that contained diploid and tetraploid species in a way that tetraploid species were grouped in between their diploid parental species with varying genetic distances. Present findings confirmed the validity of SSR markers in genomic studies. (author)

Assessment of Genetic Diversity in Opuntia spp. Portuguese Populations Using SSR Molecular Markers

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Carlos M. G. Reis

2018-04-01

Full Text Available The Opuntia spp., most likely few individuals, were introduced in the Iberian Peninsula in the beginning of the 16th century, after the discovery of America, spreading afterwards throughout the Mediterranean basin. We analysed, for the first time, the genetic diversity in a set of 19 Portuguese Opuntia spp. populations from the species O. ficus-indica, O. elata, O. dillenii and O. robusta using nuclear microsatellite (nuSSR markers. The Italian cultivars ‘Bianca’, ‘Gialla’ and ‘Rossa’ were included in the study for comparison purposes. The nuSSR amplifications produced from five to 16 alleles, with an average of 9.2 alleles per primer pair, and average polymorphism information content of 0.71. The estimated Dice coefficient among populations varied from 0.26 to 1.0, indicating high interspecific genetic diversity but low genetic diversity at the intraspecific level. The hierarchical clustering analysis revealed four major groups that clearly separated the four Opuntia species. Among the O. ficus-indica populations, two sub-clusters were found, one including the white pulp fruits (with cv. Bianca and the other with the orange pulp ones and including the cv. Gialla, the cv. Rossa, and one pale yellow pulp population. No genetic differences were found between the inermis form, O. ficus-indica f. ficus-indica, and the rewilded spiny one, O. ficus-indica f. amyclaea. The dendrogram indicated that the clustering pattern was unrelated to geographical origin. The results revealed a low level of genetic diversity among the Portuguese populations of O. ficus-indica.

Discovery and introgression of the wild sunflower-derived novel downy mildew resistance gene Pl 19 in confection sunflower (Helianthus annuus L.).

Science.gov (United States)

Zhang, Z W; Ma, G J; Zhao, J; Markell, S G; Qi, L L

2017-01-01

A new downy mildew resistance gene, Pl 19 , was identified from wild Helianthus annuus accession PI 435414, introduced to confection sunflower, and genetically mapped to linkage group 4 of the sunflower genome. Wild Helianthus annuus accession PI 435414 exhibited resistance to downy mildew, which is one of the most destructive diseases to sunflower production globally. Evaluation of the 140 BC 1 F 2:3 families derived from the cross of CMS CONFSCLB1 and PI 435414 against Plasmopara halstedii race 734 revealed that a single dominant gene controls downy mildew resistance in the population. Bulked segregant analysis conducted in the BC 1 F 2 population with 860 simple sequence repeat (SSR) markers indicated that the resistance derived from wild H. annuus was associated with SSR markers located on linkage group (LG) 4 of the sunflower genome. To map and tag this resistance locus, designated Pl 19 , 140 BC 1 F 2 individuals were used to construct a linkage map of the gene region. Two SSR markers, ORS963 and HT298, were linked to Pl 19 within a distance of 4.7 cM. After screening 27 additional single nucleotide polymorphism (SNP) markers previously mapped to this region, two flanking SNP markers, NSA_003564 and NSA_006089, were identified as surrounding the Pl 19 gene at a distance of 0.6 cM from each side. Genetic analysis indicated that Pl 19 is different from Pl 17 , which had previously been mapped to LG4, but is closely linked to Pl 17 . This new gene is highly effective against the most predominant and virulent races of P. halstedii currently identified in North America and is the first downy mildew resistance gene that has been transferred to confection sunflower. The selected resistant germplasm derived from homozygous BC 2 F 3 progeny provides a novel gene for use in confection sunflower breeding programs.

Using SSR-HRM to Identify Closely Related Species in Herbal Medicine Products: A Case Study on Licorice.

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Li, Jingjian; Xiong, Chao; He, Xia; Lu, Zhaocen; Zhang, Xin; Chen, Xiaoyang; Sun, Wei

2018-01-01

Traditional herbal medicines have played important roles in the ways of life of people around the world since ancient times. Despite the advanced medical technology of the modern world, herbal medicines are still used as popular alternatives to synthetic drugs. Due to the increasing demand for herbal medicines, plant species identification has become an important tool to prevent substitution and adulteration. Here we propose a method for biological assessment of the quality of prescribed species in the Chinese Pharmacopoeia by use of high resolution melting (HRM) analysis of microsatellite loci. We tested this method on licorice, a traditional herbal medicine with a long history. Results showed that nine simple sequence repeat (SSR) markers produced distinct melting curve profiles for the five licorice species investigated using HRM analysis. These results were validated by capillary electrophoresis. We applied this protocol to commercially available licorice products, thus enabling the consistent identification of 11 labels with non-declared Glycyrrhiza species. This novel strategy may thus facilitate DNA barcoding as a method of identification of closely related species in herbal medicine products. Based on this study, a brief operating procedure for using the SSR-HRM protocol for herbal authentication is provided.

EST-PAC a web package for EST annotation and protein sequence prediction

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Strahm Yvan

2006-10-01

Full Text Available Abstract With the decreasing cost of DNA sequencing technology and the vast diversity of biological resources, researchers increasingly face the basic challenge of annotating a larger number of expressed sequences tags (EST from a variety of species. This typically consists of a series of repetitive tasks, which should be automated and easy to use. The results of these annotation tasks need to be stored and organized in a consistent way. All these operations should be self-installing, platform independent, easy to customize and amenable to using distributed bioinformatics resources available on the Internet. In order to address these issues, we present EST-PAC a web oriented multi-platform software package for expressed sequences tag (EST annotation. EST-PAC provides a solution for the administration of EST and protein sequence annotations accessible through a web interface. Three aspects of EST annotation are automated: 1 searching local or remote biological databases for sequence similarities using Blast services, 2 predicting protein coding sequence from EST data and, 3 annotating predicted protein sequences with functional domain predictions. In practice, EST-PAC integrates the BLASTALL suite, EST-Scan2 and HMMER in a relational database system accessible through a simple web interface. EST-PAC also takes advantage of the relational database to allow consistent storage, powerful queries of results and, management of the annotation process. The system allows users to customize annotation strategies and provides an open-source data-management environment for research and education in bioinformatics.

De novo transcriptomic analysis of cowpea (Vigna unguiculata L. Walp.) for genic SSR marker development.

Science.gov (United States)

Chen, Honglin; Wang, Lixia; Liu, Xiaoyan; Hu, Liangliang; Wang, Suhua; Cheng, Xuzhen

2017-07-11

Cowpea [Vigna unguiculata (L.) Walp.] is one of the most important legumes in tropical and semi-arid regions. However, there is relatively little genomic information available for genetic research on and breeding of cowpea. The objectives of this study were to analyse the cowpea transcriptome and develop genic molecular markers for future genetic studies of this genus. Approximately 54 million high-quality cDNA sequence reads were obtained from cowpea based on Illumina paired-end sequencing technology and were de novo assembled to generate 47,899 unigenes with an N50 length of 1534 bp. Sequence similarity analysis revealed 36,289 unigenes (75.8%) with significant similarity to known proteins in the non-redundant (Nr) protein database, 23,471 unigenes (49.0%) with BLAST hits in the Swiss-Prot database, and 20,654 unigenes (43.1%) with high similarity in the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Further analysis identified 5560 simple sequence repeats (SSRs) as potential genic molecular markers. Validating a random set of 500 SSR markers yielded 54 polymorphic markers among 32 cowpea accessions. This transcriptomic analysis of cowpea provided a valuable set of genomic data for characterizing genes with important agronomic traits in Vigna unguiculata and a new set of genic SSR markers for further genetic studies and breeding in cowpea and related Vigna species.

Identification and genetic mapping of highly polymorphic microsatellite loci from an EST database of the septoria tritici blotch pathogen Mycosphaerella graminicola.

Science.gov (United States)

Goodwin, Stephen B; van der Lee, Theo A J; Cavaletto, Jessica R; Te Lintel Hekkert, Bas; Crane, Charles F; Kema, Gert H J

2007-05-01

A database of 30,137 EST sequences from Mycosphaerella graminicola, the septoria tritici blotch fungus of wheat, was scanned with a custom software pipeline for di- and trinucleotide units repeated tandemly six or more times. The bioinformatics analysis identified 109 putative SSR loci, and for 99 of them, flanking primers were developed successfully and tested for amplification and polymorphism by PCR on five field isolates of diverse origin, including the parents of the standard M. graminicola mapping population. Seventy-seven of the 99 primer pairs generated an easily scored banding pattern and 51 were polymorphic, with up to four alleles per locus, among the isolates tested. Among these 51 loci, 23 were polymorphic between the parents of the mapping population. Twenty-one of these as well as two previously published microsatellite loci were positioned on the existing genetic linkage map of M. graminicola on 13 of the 24 linkage groups. Most (66%) of the primer pairs also amplified bands in the closely related barley pathogen Septoria passerinii, but only six were polymorphic among four isolates tested. A subset of the primer pairs also revealed polymorphisms when tested with DNA from the related banana black leaf streak (Black Sigatoka) pathogen, M. fijiensis. The EST database provided an excellent source of new, highly polymorphic microsatellite markers that can be multiplexed for high-throughput genetic analyses of M. graminicola and related species.

Releyendo Frankfurt: la Experiencia Estética en Adorno

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Stra, Sebastián Matías

2013-01-01

Full Text Available [es]Intentaremos en este trabajo explorar la noción de Experiencia Estética en la obra de Theodor Adorno, entendiéndola como una compleja mediación conceptual que nos puede permitir dar cuenta de las oscuras configuraciones de la relación entre arte, cultura y conocimiento en la producción del pensador de Frankfurt. En este marco, cruzaremos las reflexiones estéticas adornianas con lecturas más cercanas a nuestro campo disciplinar, como la noción de Industria Cultural y la interpretación del mito y su derivación en la conformación de la racionalidad moderna. [en] In this work, we will try to explore the notion of Aesthetic Experience in Theodor Adorno`s work, understanding it as a complex conceptual mediation that can allow us getting in the dark settings of the relationship between art, culture and knowledge in the production of Frankfurt`s thinker. Like this, we are going to cross adornians aesthetic reflections with readings that are going to be closer to our disciplinary field, as the notion of cultural industry and the interpretation of myth and its derivation in the configuration of modern rationality.

SSR based genetic diversity of pigmented and aromatic rice (Oryza sativa L.) genotypes of the western Himalayan region of India.

Science.gov (United States)

Ashraf, Humaira; Husaini, Amjad M; Ashraf Bhat, M; Parray, G A; Khan, Salim; Ganai, Nazir A

2016-10-01

A set of 24 of SSR markers were used to estimate the genetic diversity in 16 rice genotypes found in Western Himalayas of Kashmir and Himachal Pradesh, India. The level of polymorphism among the genotypes of rice was evaluated from the number of alleles and PIC value for each of the 24 SSR loci. A total of 68 alleles were detected across the 16 genotypes through the use of these 24 SSR markers The number of alleles per locus generated varied from 2 (RM 338, RM 452, RM 171) to 6 (RM 585, RM 249, RM 481, RM 162). The PIC values varied from 0.36 (RM 1) to 0.86 (RM 249) with an average of 0.62 per locus. Based on information generated, the genotypes got separated in six different clusters. Cluster 1 comprised of 4 genotypes viz; Zag 1, Zag 13, Pusa sugandh 3, and Zag 14, separated from each other at a similarity value of 0.40. Cluster second comprised of 3 landraces viz; Zag 2. Zag 4 and Zag10 separated from each other at a similarity value of 0.45. Cluster third comprised of 3 genotypes viz; Grey rice, Mushk budji and Kamad separated from each other at a similarity value of 0.46. Cluster fourth had 2 landraces viz; Kawa kreed and Loual anzul, and was not sub clustered. Fifth cluster had 3 genotypes viz; Zag 12, Purple rice and Jhelum separated from each other at a similarity value of 0.28. Cluster 6 comprised of a single popular variety i.e. Shalimar rice 1 with independent lineage.

EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

NARCIS (Netherlands)

Studer, B.; Kolliker, R.; Muylle, H.; Asp, T.; Frei, U.; Roldan-Ruiz, I.; Barre, P.; Tomaszewski, C.; Meally, H.; Barth, S.; Skot, L.; Armstead, I.P.; Dolstra, O.; Lubberstedt, T.

2010-01-01

Background: Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps

A genetic linkage map with 178 SSR and 1 901 SNP markers constructed using a RIL population in wheat （Triticum aestivum L.）

Institute of Scientific and Technical Information of China (English)

ZHAI Hui-jie; FENG Zhi-yu; LIU Xin-ye; CHENG Xue-jiao; PENG Hui-ru; YAO Ying-yin; SUN Qi-xin; NI Zhong-fu

2015-01-01

The construction of high density genetic linkage map provides a powerful tool to detect and map quantitative trait loci （QTLs） controlling agronomically important traits. In this study, simple sequence repeat （SSR） markers and Illumina 9K iSelect single nucleotide polymorphism （SNP） genechip were employed to construct one genetic linkage map of common wheat （Triticum aestivum L.） using 191 recombinant inbred lines （RILs） derived from cross Yu 8679xJing 411. This map included 1 901 SNP loci and 178 SSR loci, covering 1 659.9 cM and 1 000 marker bins, with an average interval distance of 1.66 cM. A, B and D genomes covered 719.1,703.5 and 237.3 cM, with an average interval distance of 1.66, 1.45 and 2.9 cM, respectively. Notably, the genetic linkage map covered 20 chromosomes, with the exception of chromosome 5D. Bioinformatics analysis revealed that 1 754 （92.27%） of 1 901 mapped SNP loci could be aligned to 1 215 distinct wheat unigenes, among which 1 184 （97.4%） were located on one single chromosome, and the rest 31 （2.6%） were located on 2 to 3 chromosomes. By performing in silico comparison, 214 chromosome deletion bin-mapped expressed sequence tags （ESTs）, 1 043 Brachypodium genes and 1 033 rice genes were further added onto the genetic linkage map. This map not only integrated genetic and physical maps, SSR and SNP loci, respectively, but also provided the information of Brachypodium and rice genes corresponding to 1 754 SNP loci. Therefore, it will be a useful tool for comparative genomics analysis, fine mapping of QTL/gene controlling agronomically important traits and marker-assisted selection breeding in wheat.

Disomic Inheritance and Segregation Distortion of SSR Markers in Two Populations of Cynodon dactylon (L.) Pers. var. dactylon.

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Guo, Yuanwen; Wu, Yanqi; Anderson, Jeff A; Moss, Justin Q; Zhu, Lan

2015-01-01

Common bermudagrass [C. dactylon (L.) Pers. var. dactylon] is economically and environmentally the most important member among Cynodon species because of its extensive use for turf, forage and soil erosion control in the world. However, information regarding the inheritance within the taxon is limited. Accordingly, the objective of this study was to determine qualitative inheritance mode in common bermudagrass. Two tetraploid (2n = 4x = 36), first-generation selfed (S1) populations, 228 progenies of 'Zebra' and 273 from A12359, were analyzed for segregation with 21 and 12 simple sequence repeat (SSR) markers, respectively. It is concluded that the inheritance mode of tetraploid bermudagrass was complete or near complete disomic. It is evident that the two bermudagrass parents had an allotetraploid genome with two distinct subgenomes since 33 SSR primer pairs amplified 34 loci, each having two alleles. Severe transmission ratio distortions occurred in the Zebra population while less so in the A12359 population. The findings of disomic inheritance and segregation ratio distortion in common bermudagrass is significant in subsequent linkage map construction, quantitative trait locus mapping and marker-assisted selection in the species.

Report on the development of putative functional SSR and SNP markers in passion fruits.

Science.gov (United States)

da Costa, Zirlane Portugal; Munhoz, Carla de Freitas; Vieira, Maria Lucia Carneiro

2017-09-06

Passionflowers Passiflora edulis and Passiflora alata are diploid, outcrossing and understudied fruit bearing species. In Brazil, passion fruit cultivation began relatively recently and has earned the country an outstanding position as the world's top producer of passion fruit. The fruit's main economic value lies in the production of juice, an essential exotic ingredient in juice blends. Currently, crop improvement strategies, including those for underexploited tropical species, tend to incorporate molecular genetic approaches. In this study, we examined a set of P. edulis transcripts expressed in response to infection by Xanthomonas axonopodis, (the passion fruit's main bacterial pathogen that attacks the vines), aiming at the development of putative functional markers, i.e. SSRs (simple sequence repeats) and SNPs (single nucleotide polymorphisms). A total of 210 microsatellites were found in 998 sequences, and trinucleotide repeats were found to be the most frequent (31.4%). Of the sequences selected for designing primers, 80.9% could be used to develop SSR markers, and 60.6% SNP markers for P. alata. SNPs were all biallelic and found within 15 gene fragments of P. alata. Overall, gene fragments generated 10,003 bp. SNP frequency was estimated as one SNP every 294 bp. Polymorphism rates revealed by SSR and SNP loci were 29.4 and 53.6%, respectively. Passiflora edulis transcripts were useful for the development of putative functional markers for P. alata, suggesting a certain level of sequence conservation between these cultivated species. The markers developed herein could be used for genetic mapping purposes and also in diversity studies.

Evaluation of Mungbean Mutant Lines to Drought Stress and Their Genetic Relationships Using SSR Markers

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Yuliasti

2015-12-01

Full Text Available Development of mungbean cultivarstolerant to drought stress through mutation breeding approach would enable us to anticipate the crop yield-reducing effects of climate changes. The objective of this research was to evaluate the yield performance of mungbean mutant lines that showed tolerance to drought stress, and to analyze their genetic diversity and relationship among mutant lines using SSR markers. The study was conducted during the dry season of 2012 in the Muneng experimental farm, Probolinggo, East Java. The experiment was laid out in a randomized block design with four replications. Five mutant lines and two parental lines as control were tested for evaluation of yield and drought tolerance under twoenvironments of two irrigation systems as treatment. The two environmental conditions consisted of optimal irrigation (at least three times: at planting, flowering and during pod filling and suboptimal irrigation (two times at planting and flowering. To evaluate genetic variation among selected mutant lines and their discrimination from parental lines in molecular level, a cluster analysis was performed using Unweighted Pair Group Method with Arithmetic Mean (UPGMA in the NTSYS software. The results showed that three mutant lines, including PsJ30, PsJ31, PsJ32 produced the highest grain yields of 1.17, 1.01, and 1.04 ton/ha, respectively, compared to the other mutant lines and the parents Gelatik (0.85 ton/ha and Perkutut (0.87 ton/ha as control check. Of those mutant lines, PSJ31 was the most tolerant to drought with sensitivity index value of 0.47. The PSJ31 has now been officially released as a new variety ( 2013, named as Muri which was identified to have high yield and tolerant to drought. Based on 23 SSR markers used for clustering analysis of those 3 selected mutant lines,9SSR markers (MBSS R033; satt137; MBSSR008; MBSSR203; MBSSR013; MBSSR021; MBSSR016; MBSSR136; and DMBSSR013 were successfully identified the three mungbean mutant

Development and Characterization of Microsatellite Markers from the Transcriptome of Firmiana danxiaensis (Malvaceae s.l.

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Qiang Fan

2013-11-01

Full Text Available Premise of the study: Firmiana consists of 12–16 species, many of which are narrow endemics. Expressed sequence tag (EST–simple sequence repeat (SSR markers were developed and characterized for size polymorphism in four Firmiana species. Methods and Results: A total of 102 EST-SSR primer pairs were designed based on the transcriptome sequences of F. danxiaensis; these were then characterized in four Firmiana species—F. danxiaensis, F. kwangsiensis, F. hainanensis, and F. simplex. In these four species, 17 primer pairs were successfully amplified, and 14 were polymorphic in at least one species. The number of alleles ranged from one to 13, and the observed and expected heterozygosities ranged from 0 to 1 and 0 to 0.925, respectively. The lowest level of polymorphism was observed in F. danxiaensis. Conclusions: These polymorphic EST-SSR markers are valuable for conservation genetics studies in the endangered Firmiana species.

Species discrimination, population structure and linkage disequilibrium in Eucalyptus camaldulensis and Eucalyptus tereticornis using SSR markers.

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Shanmugapriya Arumugasundaram

Full Text Available Eucalyptus camaldulensis and E. tereticornis are closely related species commonly cultivated for pulp wood in many tropical countries including India. Understanding the genetic structure and linkage disequilibrium (LD existing in these species is essential for the improvement of industrially important traits. Our goal was to evaluate the use of simple sequence repeat (SSR loci for species discrimination, population structure and LD analysis in these species. Investigations were carried out with the most common alleles in 93 accessions belonging to these two species using 62 SSR markers through cross amplification. The polymorphic information content (PIC ranged from 0.44 to 0.93 and 0.36 to 0.93 in E. camaldulensis and E. tereticornis respectively. A clear delineation between the two species was evident based on the analysis of population structure and species-specific alleles. Significant genotypic LD was found in E. camaldulensis, wherein out of 135 significant pairs, 17 pairs showed r(2≥0.1. Similarly, in E. tereticornis, out of 136 significant pairs, 18 pairs showed r(2≥0.1. The extent of LD decayed rapidly showing the significance of association analyses in eucalypts with higher resolution markers. The availability of whole genome sequence for E. grandis and the synteny and co-linearity in the genome of eucalypts, will allow genome-wide genotyping using microsatellites or single nucleotide polymorphims.

Genomic rearrangements and signatures of breeding in the allo-octoploid strawberry as revealed through an allele dose based SSR linkage map

NARCIS (Netherlands)

Dijk, van T.; Pagliarani, G.; Pikunova, A.; Noordijk, Y.; Yilmaz-Temel, H.; Meulenbroek, B.; Visser, R.G.F.; Weg, van de W.E.

2014-01-01

Background Breeders in the allo-octoploid strawberry currently make little use of molecular marker tools. As a first step of a QTL discovery project on fruit quality traits and resistance to soil-borne pathogens such as Phytophthora cactorum and Verticillium we built a genome-wide SSR linkage map

Genic Microsatellite Markers in Brassica rapa: Development, Characterization, Mapping, and Their Utility in Other Cultivated and Wild Brassica Relatives

Science.gov (United States)

Ramchiary, Nirala; Nguyen, Van Dan; Li, Xiaonan; Hong, Chang Pyo; Dhandapani, Vignesh; Choi, Su Ryun; Yu, Ge; Piao, Zhong Yun; Lim, Yong Pyo

2011-01-01

Genic microsatellite markers, also known as functional markers, are preferred over anonymous markers as they reveal the variation in transcribed genes among individuals. In this study, we developed a total of 707 expressed sequence tag-derived simple sequence repeat markers (EST-SSRs) and used for development of a high-density integrated map using four individual mapping populations of B. rapa. This map contains a total of 1426 markers, consisting of 306 EST-SSRs, 153 intron polymorphic markers, 395 bacterial artificial chromosome-derived SSRs (BAC-SSRs), and 572 public SSRs and other markers covering a total distance of 1245.9 cM of the B. rapa genome. Analysis of allelic diversity in 24 B. rapa germplasm using 234 mapped EST-SSR markers showed amplification of 2 alleles by majority of EST-SSRs, although amplification of alleles ranging from 2 to 8 was found. Transferability analysis of 167 EST-SSRs in 35 species belonging to cultivated and wild brassica relatives showed 42.51% (Sysimprium leteum) to 100% (B. carinata, B. juncea, and B. napus) amplification. Our newly developed EST-SSRs and high-density linkage map based on highly transferable genic markers would facilitate the molecular mapping of quantitative trait loci and the positional cloning of specific genes, in addition to marker-assisted selection and comparative genomic studies of B. rapa with other related species. PMID:21768136

Evaluation of rice germplasm under salt stress at the seedling stage through SSR markers

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M. Al-Amin

2013-06-01

Full Text Available Twenty eight rice germplasms were used for identification of salt tolerant rice genotypes at the seedling stage at the experimental farm and Biotechnology laboratory of the Bangladesh Institute of Nuclear Agriculture (BINA, Mymensingh during February 2009 to October 2009. Phenotyping for salinity screening of the rice genotypes was done using salinized (EC level 12 dS m-1 nutrient solution in hydroponic system. Genotypes were evaluated for salinity tolerance on 1-9 scale based on seedling growth parameters following modified Standard Evaluation Scoring (SES of IRRI. Phenotypically, on the basis of SES and % total dry matter (TDM reduction of the genotypes viz. PBSAL-614, PBSAL-613, PBSAL-730, Horkuch, S-478/3 Pokkali and PBSAL (STL-15 were found to be salt tolerant; on the other hand Iratom-24, S-653/32, S-612/32, S-604/32, S-633/32, Charnock (DA6, BINA Dhan-6 and S-608/32 were identified as salt susceptible. For genotyping, ten SSR markers were used for polymorphism, where 3 primers (RM127, RM443 and RM140 were selected for evaluation of salt tolerance. In respect of Primer RM127, 7 lines were found salt tolerant and 11 lines were moderately tolerant and 10 lines were susceptible. Nine tolerant, 9 moderately tolerant and 10 susceptible lines were found when the primer RM140 was used and primer RM443 identified 8 lines as tolerant, 9 lines as moderately tolerant and 11 lines as susceptible. Thus, the salt tolerant lines can be used in further evaluation for salinity tolerance and the SSR markers used in this study are proving valuable for identifying salt tolerant genes in marker assisted breeding.

AcEST: DK948090 [AcEST

Lifescience Database Archive (English)

Full Text Available erase A OS=Aspergillus tubingen... 50 1e-05 sp|P0C1S9|DGLB_RAT Sn1-specific diacy...|P47145|YJ77_YEAST Putative lipase YJR107W OS=Saccharomyces ce... 50 8e-06 sp|O42815|FAEA_ASPTU Feruloyl est

Field Performance of Five Soybean Mutants Under Drought Stress Conditions and Molecular Analysis Using SSR Markers

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Y Yuliasti

2017-08-01

Full Text Available The objectives of this research wereto evaluate (1 the performance of soybean mutant lines under drought stress conditions, and(2 the genetic diversity and relationship among the mutant lines using SSR markers.The field evaluation was conducted during the dry season of 2011 and 2012 at the experimental Farm of Mataram University, West Nusa Tenggara, Indonesia. The field experiment was set up in a randomized block design. Ten mutant lines and two control varieties were evaluated in four replications. Genetic distance among evaluated lines were determined based on allelic diversity analysis using 40 simple sequence repeat (SSR loci. Under drought stress conditions, two mutant lines, Kdl3 and Kdl8,showed a better performance compared to the other ones. The high yielding mutant lines were Kdl3and Kdl8, which yielded 1.75 t ha-1and 1.69 t ha-1, respectively, compared to the parent and national control, Panderman 1.43 t ha-1 and Muria 1.32 t ha-1. These mutant linesrequired 30.75 to 32days to flower and 79.75 to 83.75 day to harvest with relatively short plant height 28.25 and 23.35 cmrespectively. Those mutant characters were better than those of the other three mutants, the original parents, and the control soybean species. Since the evaluated soybean mutant lines yielded more under drought stress conditions than the standard varieties, they can be used and registered as drought-tolerant soybean mutants. Moreover, the evaluated soybean accessions showed a wide genetic distance. The accessions were clustered into two groups according to their genetic background, namelygroup I (the Panderman with three mutant lines and group II (the Muria with two mutant lines. Twenty-three out of 40 evaluated SSR loci, including AW31, BE806, CMAC7L, S080, S126, S57, S171, S224, S285, S294, S393, S294, S383, S511, S511, S520, S540, S547, S551, S571, S577, and S578, provided polymorphic alleles between the parents and their mutants and could be used to differentiate

Development and characterization of EST-SSR markers for Artocarpus hypargyreus (Moraceae).

Science.gov (United States)

Liu, Haijun; Tan, Weizheng; Sun, Hongbin; Liu, Yu; Meng, Kaikai; Liao, Wenbo

2016-12-01

Polymorphic microsatellite markers were developed for Artocarpus hypargyreus (Moraceae), a threatened species endemic to China, to investigate the genetic diversity and structure of the species. Based on the transcriptome data of A. hypargyreus , 63 primer pairs were preliminarily designed and tested, of which 34 were successfully amplified and 10 displayed clear polymorphisms across the 67 individuals from four populations of A. hypargyreus . The results showed the number of alleles per locus ranged from three to 10, and the observed heterozygosity and expected heterozygosity per locus varied from 0.000 to 0.706 and from 0.328 to 0.807, respectively. These microsatellite markers will be useful in exploring genetic diversity and structure of A. hypargyreus . Furthermore, most loci were successfully cross-amplified in A. nitidus and A. heterophyllus , indicating that they will be of great value for genetic study across this genus.

SSR mining in oil palm EST database: application in oil palm ...

Indian Academy of Sciences (India)

1Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, P.O. Box 10620,. 50720 Kuala Lumpur .... Genomic DNA was extracted from young leaves. The DNA ..... tries are essential to avoid the risk of genetic erosion. The.

Genetic Linkage Map Construction and QTL Analysis of Two Interspecific Reproductive Isolation Traits in Sponge Gourd.

Science.gov (United States)

Wu, Haibin; He, Xiaoli; Gong, Hao; Luo, Shaobo; Li, Mingzhu; Chen, Junqiu; Zhang, Changyuan; Yu, Ting; Huang, Wangping; Luo, Jianning

2016-01-01

The hybrids between Luffa acutangula (L.) Roxb. and L.cylindrica (L.) Roem. have strong heterosis effects. However, some reproductive isolation traits hindered their normal hybridization and fructification, which was mainly caused by the flowering time and hybrid pollen sterility. In order to study the genetic basis of two interspecific reproductive isolation traits, we constructed a genetic linkage map using an F2 population derived from a cross between S1174 [L. acutangula (L.) Roxb.] and 93075 [L. cylindrica (L.) Roem.]. The map spans 1436.12 CentiMorgans (cM), with an average of 8.11 cM among markers, and consists of 177 EST-SSR markers distributed in 14 linkage groups (LG) with an average of 102.58 cM per LG. Meanwhile, we conducted colinearity analysis between the sequences of EST-SSR markers and the genomic sequences of cucumber, melon and watermelon. On the basis of genetic linkage map, we conducted QTL mapping of two reproductive isolation traits in sponge gourd, which were the flowering time and hybrid male sterility. Two putative QTLs associated with flowering time (FT) were both detected on LG 1. The accumulated contribution of these two QTLs explained 38.07% of the total phenotypic variance (PV), and each QTL explained 15.36 and 22.71% of the PV respectively. Four QTLs for pollen fertility (PF) were identified on LG 1 (qPF1.1 and qPF1.2), LG 3 (qPF3) and LG 7 (qPF7), respectively. The percentage of PF explained by these QTLs varied from 2.91 to 16.79%, and all together the four QTLs accounted for 39.98% of the total PV. Our newly developed EST-SSR markers and linkage map are very useful for gene mapping, comparative genomics and molecular marker-assisted breeding. These QTLs for interspecific reproductive isolation will also contribute to the cloning of genes relating to interspecific reproductive isolation and the utilization of interspecific heterosis in sponge gourd in further studies.

Crystal structure of hyperthermophilic esterase EstE1 and the relationship between its dimerization and thermostability properties

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Koh Eunhee

2007-07-01

Full Text Available Abstract Background EstE1 is a hyperthermophilic esterase belonging to the hormone-sensitive lipase family and was originally isolated by functional screening of a metagenomic library constructed from a thermal environmental sample. Dimers and oligomers may have been evolutionally selected in thermophiles because intersubunit interactions can confer thermostability on the proteins. The molecular mechanisms of thermostabilization of this extremely thermostable esterase are not well understood due to the lack of structural information. Results Here we report for the first time the 2.1-Å resolution crystal structure of EstE1. The three-dimensional structure of EstE1 exhibits a classic α/β hydrolase fold with a central parallel-stranded beta sheet surrounded by alpha helices on both sides. The residues Ser154, Asp251, and His281 form the catalytic triad motif commonly found in other α/β hydrolases. EstE1 exists as a dimer that is formed by hydrophobic interactions and salt bridges. Circular dichroism spectroscopy and heat inactivation kinetic analysis of EstE1 mutants, which were generated by structure-based site-directed mutagenesis of amino acid residues participating in EstE1 dimerization, revealed that hydrophobic interactions through Val274 and Phe276 on the β8 strand of each monomer play a major role in the dimerization of EstE1. In contrast, the intermolecular salt bridges contribute less significantly to the dimerization and thermostability of EstE1. Conclusion Our results suggest that intermolecular hydrophobic interactions are essential for the hyperthermostability of EstE1. The molecular mechanism that allows EstE1 to endure high temperature will provide guideline for rational design of a thermostable esterase/lipase using the lipolytic enzymes showing structural similarity to EstE1.

Comparative expression profiling in grape (Vitis vinifera berries derived from frequency analysis of ESTs and MPSS signatures

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Cook Douglas R

2008-05-01

Full Text Available Abstract Background Vitis vinifera (V. vinifera is the primary grape species cultivated for wine production, with an industry valued annually in the billions of dollars worldwide. In order to sustain and increase grape production, it is necessary to understand the genetic makeup of grape species. Here we performed mRNA profiling using Massively Parallel Signature Sequencing (MPSS and combined it with available Expressed Sequence Tag (EST data. These tag-based technologies, which do not require a priori knowledge of genomic sequence, are well-suited for transcriptional profiling. The sequence depth of MPSS allowed us to capture and quantify almost all the transcripts at a specific stage in the development of the grape berry. Results The number and relative abundance of transcripts from stage II grape berries was defined using Massively Parallel Signature Sequencing (MPSS. A total of 2,635,293 17-base and 2,259,286 20-base signatures were obtained, representing at least 30,737 and 26,878 distinct sequences. The average normalized abundance per signature was ~49 TPM (Transcripts Per Million. Comparisons of the MPSS signatures with available Vitis species' ESTs and a unigene set demonstrated that 6,430 distinct contigs and 2,190 singletons have a perfect match to at least one MPSS signature. Among the matched sequences, ESTs were identified from tissues other than berries or from berries at different developmental stages. Additional MPSS signatures not matching to known grape ESTs can extend our knowledge of the V. vinifera transcriptome, particularly when these data are used to assist in annotation of whole genome sequences from Vitis vinifera. Conclusion The MPSS data presented here not only achieved a higher level of saturation than previous EST based analyses, but in doing so, expand the known set of transcripts of grape berries during the unique stage in development that immediately precedes the onset of ripening. The MPSS dataset also revealed

Open reading frame ssr2016 is required for antimycin A-sensitive photosystem I-driven cyclic electron flow in the cyanobacterium Synechocystis sp. PCC 6803

NARCIS (Netherlands)

Yeremenko, Nataliya; Jeanjean, Robert; Prommeenate, Peerada; Krasikov, Vladimir; Nixon, Peter J.; Vermaas, Wim F. J.; Havaux, Michel; Matthijs, Hans C. P.

2005-01-01

Open reading frame ssr2016 encodes a protein with substantial sequence similarities to PGR5 identified as a component of the antimycin A-sensitive ferredoxin:plastoquinone reductase (FQR) in PSI cyclic photophosphorylation in Arabidopsis thaliana. We studied cyclic electron flow in Synechocystis sp.

Comparative analysis of genetic diversity among Chinese watermelon germplasmsusing SSR and SRAP markers, and implications for future genetic improvement

OpenAIRE

WANG, PANGQIAO; LI, QIONG; Hu, Jianbin; SU, YAN

2015-01-01

The genetic diversity of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] in China, the world's largest producer of watermelon fruits, has not been examined. Two molecular markers, sequence-related amplified polymorphism (SRAP) and simple sequence repeat (SSR), were used to investigate the genetic variation and genetic relationship among 54 Chinese watermelon accessions, as well as 7 accessions from Africa, the United States, and Japan. SRAP assay generated 312 bands, ...

SSR-Based DNA Fingerprinting and Diversity Assessment Among Indian Germplasm of Euryale ferox: an Aquatic Underutilized and Neglected Food Crop.

Science.gov (United States)

Kumar, Nitish; Shikha, Divya; Kumari, Swati; Choudhary, Binod Kumar; Kumar, Lokendra; Singh, Indu Shekhar

2017-10-30

Euryale ferox is native to Southeast Asia and China, and it is one of the important aquatic food crops propagated mostly in eastern part of India. The aim of the present study was to characterize and evaluate the genetic diversity of ex situ collections of E. ferox germplasm from different geographical states of India using microsatellite (simple sequence repeats (SSRs)) markers. Ten SSR markers were analyzed to assess DNA fingerprinting and genetic diversity of 16 cultivated germplasm of E. ferox. Total 37 polymorphic alleles were recorded with an average of 3.7 allele frequency per primer. The polymorphic information content value varied from 0.204 to 0.735 with mean of 0.448. A high range of heterozygosity (Ho 0.228; He 0.512) was detected in the present study. The neighbor-joining (N-J) tree and the principle coordinate analysis showed that the germplasm divided in to three main clusters. The results of the present investigation comply that SSR markers are effective for computing genetic assessment of genetic diversity and similarity with classifying cultivated varieties of E. ferox. Evaluation of genetic diversity among Indian E. ferox germplasm could provide useful information for genetic improvement.

Association mapping of agro-morphological characters among the global collection of finger millet genotypes using genomic SSR markers.

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Kalyana Babu, B; Agrawal, P K; Pandey, Dinesh; Jaiswal, J P; Kumar, Anil

2014-08-01

Identification of alleles responsible for various agro-morphological characters is a major concern to further improve the finger millet germplasm. Forty-six genomic SSRs were used for genetic analysis and population structure analysis of a global collection of 190 finger millet genotypes and fifteen agro-morphological characters were evaluated. The overall results showed that Asian genotypes were smaller in height, smaller flag leaf length, less basal tiller number, early flowering and early maturity nature, small ear head length, and smaller in length of longest finger. The 46 SSRs yielded 90 scorable alleles and the polymorphism information content values varied from 0.292 to 0.703 at an average of 0.442. The gene diversity was in the range of 0.355 to 0.750 with an average value of 0.528. The 46 genomic SSR loci grouped the 190 finger millet genotypes into two major clusters based on their geographical origin by the both phylogenetic clustering and population structure analysis by STRUCTURE software. Association mapping of QTLs for 15 agro-morphological characters with 46 genomic SSRs resulted in identification of five markers were linked to QTLs of four traits at a significant threshold (P) level of ≤ 0.01 and ≤ 0.001. The QTL for basal tiller number was strongly associated with the locus UGEP81 at a P value of 0.001 by explaining the phenotypic variance (R (2)) of 10.8%. The QTL for days to 50% flowering was linked by two SSR loci UGEP77 and UGEP90, explained 10 and 8.7% of R (2) respectively at a P value of 0.01. The SSR marker, FM9 found to have strong association to two agro-morphological traits, flag leaf width (P-0.001, R(2)-14.1 %) and plant height (P-0.001, R(2)-11.2%). The markers linked to the QTLs for above agro-morphological characters found in the present study can be further used for cloning of the full length gene, fine mapping and their further use in the marker assisted breeding programmes for introgression of alleles into locally well

Functional markers based molecular characterization and cloning of resistance gene analogs encoding NBS-LRR disease resistance proteins in finger millet (Eleusine coracana).

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Panwar, Preety; Jha, Anand Kumar; Pandey, P K; Gupta, Arun K; Kumar, Anil

2011-06-01

Magnaporthe grisea, the blast fungus is one of the main pathological threats to finger millet crop worldwide. A systematic search for the blast resistance gene analogs was carried out, using functional molecular markers. Three-fourths of the recognition-dependent disease resistance genes (R-genes) identified in plants encodes nucleotide binding site (NBS) leucine-rich repeat (LRR) proteins. NBS-LRR homologs have only been isolated on a limited scale from Eleusine coracana. Genomic DNA sequences sharing homology with NBS region of resistance gene analogs were isolated and characterized from resistant genotypes of finger millet using PCR based approach with primers designed from conserved regions of NBS domain. Attempts were made to identify molecular markers linked to the resistance gene and to differentiate the resistant bulk from the susceptible bulk. A total of 9 NBS-LRR and 11 EST-SSR markers generated 75.6 and 73.5% polymorphism respectively amongst 73 finger millet genotypes. NBS-5, NBS-9, NBS-3 and EST-SSR-04 markers showed a clear polymorphism which differentiated resistant genotypes from susceptible genotypes. By comparing the banding pattern of different resistant and susceptible genotypes, five DNA amplifications of NBS and EST-SSR primers (NBS-05(504,) NBS-09(711), NBS-07(688), NBS-03(509) and EST-SSR-04(241)) were identified as markers for the blast resistance in resistant genotypes. Principal coordinate plot and UPGMA analysis formed similar groups of the genotypes and placed most of the resistant genotypes together showing a high level of genetic relatedness and the susceptible genotypes were placed in different groups on the basis of differential disease score. Our results provided a clue for the cloning of finger millet blast resistance gene analogs which not only facilitate the process of plant breeding but also molecular characterization of blast resistance gene analogs from Eleusine coracana.

Epidemiology of allergic diseases of the respiratory passages in the Kazakh SSR

Energy Technology Data Exchange (ETDEWEB)

Moshkevich, V.S.

1985-01-01

Over a period of 20 years, the authors have been studying the distribution, aetiology and causes of increasing incidence of allergic respiratory diseases in various climatogeographic zones of the Kazakh SSR. Large groups of people living in towns and in the country were examined by various methods. The number of patients seeking advice in health service establishments because of allergic rhinitis and bronchial asthma was found to increase every year. A number of factors influencing the incidence of disease were pointed out, such as the character of diet, duration of the person's stay, vaccination against brucellosis, pollution of the atmosphere, local flora, climate, and other factors. Morbidity also depended on the methods of studying the epidemiology of respiratory allergoses. The obtained results will help health service authorities in taking specific measures to reduce morbidity from the mentioned pathological condition.

STUDY OF GENETIC VARIABILITY OF TRITICALE VARIETIES BY SSR MARKERS

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Jana Ondroušková

2013-04-01

Full Text Available For the detection of genetic variability ten genotypes of winter triticale (×Triticosecale Wittmack, 2n = 6x = 42; BBAARR were selected: nine varieties and one breeding line with good bread-making quality KM 4-09 with the chromosome translocation 1R.1D 5+10-2. 25 microsatellites markers located in the genome A, B, D and R were chosen for analysis. Eighty-four alleles were detected with an average of 3.36 alleles per locus were detected. For each microsatellite statistical values were calculated diversity index (DI, probabilities of identity (PI and polymorphic information content (PIC were calculated and averages statistical values are: DI 0.55, PI 0.27 and 0.5 PIC. Overall dendrogram based on the UPGMA method (Jaccards similarity coefficient significantly distinguished two groups of genotypes and these groups were divided into sub-clusters. A set of 5 SSR markers (Xwms0752, Xbarc128, Xrems1237, Xwms0861 and Xbrac170 which have the calculated PIC value higher than 0.68 that are sufficient for the identification of the analyzed genotypes was described.

Exploiting a wheat EST database to assess genetic diversity.

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Karakas, Ozge; Gurel, Filiz; Uncuoglu, Ahu Altinkut

2010-10-01

Expressed sequence tag (EST) markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum). In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F(2) individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29%) contigs and 96 (10%) singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs) and metabolism and energy (singletons). EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725) being between Harmankaya99 and Sönmez2001, and the lowest (0.622) between Aytin98 and Izgi01.

Exploiting a wheat EST database to assess genetic diversity

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Ozge Karakas

2010-01-01

Full Text Available Expressed sequence tag (EST markers have been used to assess variety and genetic diversity in wheat (Triticum aestivum. In this study, 1549 ESTs from wheat infested with yellow rust were used to examine the genetic diversity of six susceptible and resistant wheat cultivars. The aim of using these cultivars was to improve the competitiveness of public wheat breeding programs through the intensive use of modern, particularly marker-assisted, selection technologies. The F2 individuals derived from cultivar crosses were screened for resistance to yellow rust at the seedling stage in greenhouses and adult stage in the field to identify DNA markers genetically linked to resistance. Five hundred and sixty ESTs were assembled into 136 contigs and 989 singletons. BlastX search results showed that 39 (29% contigs and 96 (10% singletons were homologous to wheat genes. The database-matched contigs and singletons were assigned to eight functional groups related to protein synthesis, photosynthesis, metabolism and energy, stress proteins, transporter proteins, protein breakdown and recycling, cell growth and division and reactive oxygen scavengers. PCR analyses with primers based on the contigs and singletons showed that the most polymorphic functional categories were photosynthesis (contigs and metabolism and energy (singletons. EST analysis revealed considerable genetic variability among the Turkish wheat cultivars resistant and susceptible to yellow rust disease and allowed calculation of the mean genetic distance between cultivars, with the greatest similarity (0.725 being between Harmankaya99 and Sönmez2001, and the lowest (0.622 between Aytin98 and Izgi01.

SSR_pipeline: a bioinformatic infrastructure for identifying microsatellites from paired-end Illumina high-throughput DNA sequencing data

Science.gov (United States)

Miller, Mark P.; Knaus, Brian J.; Mullins, Thomas D.; Haig, Susan M.

2013-01-01

SSR_pipeline is a flexible set of programs designed to efficiently identify simple sequence repeats (e.g., microsatellites) from paired-end high-throughput Illumina DNA sequencing data. The program suite contains 3 analysis modules along with a fourth control module that can automate analyses of large volumes of data. The modules are used to 1) identify the subset of paired-end sequences that pass Illumina quality standards, 2) align paired-end reads into a single composite DNA sequence, and 3) identify sequences that possess microsatellites (both simple and compound) conforming to user-specified parameters. The microsatellite search algorithm is extremely efficient, and we have used it to identify repeats with motifs from 2 to 25bp in length. Each of the 3 analysis modules can also be used independently to provide greater flexibility or to work with FASTQ or FASTA files generated from other sequencing platforms (Roche 454, Ion Torrent, etc.). We demonstrate use of the program with data from the brine fly Ephydra packardi (Diptera: Ephydridae) and provide empirical timing benchmarks to illustrate program performance on a common desktop computer environment. We further show that the Illumina platform is capable of identifying large numbers of microsatellites, even when using unenriched sample libraries and a very small percentage of the sequencing capacity from a single DNA sequencing run. All modules from SSR_pipeline are implemented in the Python programming language and can therefore be used from nearly any computer operating system (Linux, Macintosh, and Windows).

SSR_pipeline: a bioinformatic infrastructure for identifying microsatellites from paired-end Illumina high-throughput DNA sequencing data.

Science.gov (United States)

Miller, Mark P; Knaus, Brian J; Mullins, Thomas D; Haig, Susan M

2013-01-01

SSR_pipeline is a flexible set of programs designed to efficiently identify simple sequence repeats (e.g., microsatellites) from paired-end high-throughput Illumina DNA sequencing data. The program suite contains 3 analysis modules along with a fourth control module that can automate analyses of large volumes of data. The modules are used to 1) identify the subset of paired-end sequences that pass Illumina quality standards, 2) align paired-end reads into a single composite DNA sequence, and 3) identify sequences that possess microsatellites (both simple and compound) conforming to user-specified parameters. The microsatellite search algorithm is extremely efficient, and we have used it to identify repeats with motifs from 2 to 25 bp in length. Each of the 3 analysis modules can also be used independently to provide greater flexibility or to work with FASTQ or FASTA files generated from other sequencing platforms (Roche 454, Ion Torrent, etc.). We demonstrate use of the program with data from the brine fly Ephydra packardi (Diptera: Ephydridae) and provide empirical timing benchmarks to illustrate program performance on a common desktop computer environment. We further show that the Illumina platform is capable of identifying large numbers of microsatellites, even when using unenriched sample libraries and a very small percentage of the sequencing capacity from a single DNA sequencing run. All modules from SSR_pipeline are implemented in the Python programming language and can therefore be used from nearly any computer operating system (Linux, Macintosh, and Windows).

Development and characterization of a Psathyrostachys huashanica Keng 7Ns chromosome addition line with leaf rust resistance.

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Wanli Du

Full Text Available The aim of this study was to characterize a Triticum aestivum-Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs disomic addition line 2-1-6-3. Individual line 2-1-6-3 plants were analyzed using cytological, genomic in situ hybridization (GISH, EST-SSR, and EST-STS techniques. The alien addition line 2-1-6-3 was shown to have two P. huashanica chromosomes, with a meiotic configuration of 2n = 44 = 22 II. We tested 55 EST-SSR and 336 EST-STS primer pairs that mapped onto seven different wheat chromosomes using DNA from parents and the P. huashanica addition line. One EST-SSR and nine EST-STS primer pairs indicated that the additional chromosome of P. huashanica belonged to homoeologous group 7, the diagnostic fragments of five EST-STS markers (BE404955, BE591127, BE637663, BF482781 and CD452422 were cloned, sequenced and compared. The results showed that the amplified polymorphic bands of P. huashanica and disomic addition line 2-1-6-3 shared 100% sequence identity, which was designated as the 7Ns disomic addition line. Disomic addition line 2-1-6-3 was evaluated to test the leaf rust resistance of adult stages in the field. We found that one pair of the 7Ns genome chromosomes carried new leaf rust resistance gene(s. Moreover, wheat line 2-1-6-3 had a superior numbers of florets and grains per spike, which were associated with the introgression of the paired P. huashanica chromosomes. These high levels of disease resistance and stable, excellent agronomic traits suggest that this line could be utilized as a novel donor in wheat breeding programs.

SSR240612 [(2R)-2-[((3R)-3-(1,3-benzodioxol-5-yl)-3-[[(6-methoxy-2-naphthyl)sulfonyl]amino]propanoyl)amino]-3-(4-[[2R,6S)-2,6-dimethylpiperidinyl]methyl]phenyl)-N-isopropyl-N-methylpropanamide hydrochloride], a new nonpeptide antagonist of the bradykinin B1 receptor: biochemical and pharmacological characterization.

Science.gov (United States)

Gougat, Jean; Ferrari, Bernard; Sarran, Lionel; Planchenault, Claudine; Poncelet, Martine; Maruani, Jeanne; Alonso, Richard; Cudennec, Annie; Croci, Tiziano; Guagnini, Fabio; Urban-Szabo, Katalin; Martinolle, Jean-Pierre; Soubrié, Philippe; Finance, Olivier; Le Fur, Gérard

2004-05-01

The biochemical and pharmacological properties of a novel non-peptide antagonist of the bradykinin (BK) B(1) receptor, SSR240612 [(2R)-2-[((3R)-3-(1,3-benzodioxol-5-yl)-3-[[(6-methoxy-2-naphthyl)sulfonyl]amino]propanoyl)amino]-3-(4-[[2R,6S)-2,6-dimethylpiperidinyl]methyl]phenyl)-N-isopropyl-N-methylpropanamide hydrochloride] were evaluated. SSR240612 inhibited the binding of [(3)H]Lys(0)-des-Arg(9)-BK to the B(1) receptor in human fibroblast MRC5 and to recombinant human B(1) receptor expressed in human embryonic kidney cells with inhibition constants (K(i)) of 0.48 and 0.73 nM, respectively. The compound selectivity for B(1) versus B(2) receptors was in the range of 500- to 1000-fold. SSR240612 inhibited Lys(0)-desAr(9)-BK (10 nM)-induced inositol monophosphate formation in human fibroblast MRC5, with an IC(50) of 1.9 nM. It also antagonized des-Arg(9)-BK-induced contractions of isolated rabbit aorta and mesenteric plexus of rat ileum with a pA(2) of 8.9 and 9.4, respectively. Antagonistic properties of SSR240612 were also demonstrated in vivo. SSR240612 inhibited des-Arg(9)-BK-induced paw edema in mice (3 and 10 mg/kg p.o. and 0.3 and 1 mg/kg i.p.). Moreover, SSR240612 reduced capsaicin-induced ear edema in mice (0.3, 3 and 30 mg/kg p.o.) and tissue destruction and neutrophil accumulation in the rat intestine following splanchnic artery occlusion/reperfusion (0.3 mg/kg i.v.). The compound also inhibited thermal hyperalgesia induced by UV irradiation (1 and 3 mg/kg p.o.) and the late phase of nociceptive response to formalin in rats (10 and 30 mg/kg p.o.). Finally, SSR240612 (20 and 30 mg/kg p.o.) prevented neuropathic thermal pain induced by sciatic nerve constriction in the rat. In conclusion, SSR240612 is a new, potent, and orally active specific non-peptide bradykinin B(1) receptor antagonist.

EST-derived SNP discovery and selective pressure analysis in Pacific white shrimp ( Litopenaeus vannamei)

Science.gov (United States)

Liu, Chengzhang; Wang, Xia; Xiang, Jianhai; Li, Fuhua

2012-09-01

Pacific white shrimp has become a major aquaculture and fishery species worldwide. Although a large scale EST resource has been publicly available since 2008, the data have not yet been widely used for SNP discovery or transcriptome-wide assessment of selective pressure. In this study, a set of 155 411 expressed sequence tags (ESTs) from the NCBI database were computationally analyzed and 17 225 single nucleotide polymorphisms (SNPs) were predicted, including 9 546 transitions, 5 124 transversions and 2 481 indels. Among the 7 298 SNP substitutions located in functionally annotated contigs, 58.4% (4 262) are non-synonymous SNPs capable of introducing amino acid mutations. Two hundred and fifty nonsynonymous SNPs in genes associated with economic traits have been identified as candidates for markers in selective breeding. Diversity estimates among the synonymous nucleotides were on average 3.49 times greater than those in non-synonymous, suggesting negative selection. Distribution of non-synonymous to synonymous substitutions (Ka/Ks) ratio ranges from 0 to 4.01, (average 0.42, median 0.26), suggesting that the majority of the affected genes are under purifying selection. Enrichment analysis identified multiple gene ontology categories under positive or negative selection. Categories involved in innate immune response and male gamete generation are rich in positively selected genes, which is similar to reports in Drosophila and primates. This work is the first transcriptome-wide assessment of selective pressure in a Penaeid shrimp species. The functionally annotated SNPs provide a valuable resource of potential molecular markers for selective breeding.

Genetic variability of a Brazilian Capsicum frutescens germplasm collection using morphological characteristics and SSR markers.

Science.gov (United States)

Carvalho, S I C; Bianchetti, L B; Ragassi, C F; Ribeiro, C S C; Reifschneider, F J B; Buso, G S C; Faleiro, F G

2017-07-06

Characterization studies provide essential information for the conservation and use of germplasm in plant breeding programs. In this study, 103 Capsicum frutescens L. accessions from the Active Germplasm Bank of Embrapa Hortaliças, representative of all five Brazilian geographic regions, were characterized based on morphological characteristics and microsatellite (or simple sequence repeat - SSR) molecular markers. Morphological characterization was carried out using 57 descriptors, and molecular characterization was based on 239 alleles from 24 microsatellite loci. From the estimates of genetic distances among accessions, based on molecular characterization, a cluster analysis was carried out, and a dendrogram was established. Correlations between morphological and molecular variables were also estimated. Twelve morphological descriptors were monomorphic for the set of C. frutescens accessions, and those with the highest degree of polymorphism were stem length (14.0 to 62.0 cm), stem diameter (1.0 to 4.2 cm), days to flowering (90 to 129), days to fruiting (100 to 140), fruit weight (0.1 to 1.4 g), fruit length (0.6 to 4.6 cm), and fruit wall thickness (0.25 to 1.5 mm). The polymorphism information content for the SSR loci varied from 0.36 (EPMS 417) to 0.75 (CA49), with an overall mean of 0.57. The correlation value between morphological and molecular characterization data was 0.6604, which was statistically significant. Fourteen accessions were described as belonging to the morphological type tabasco, 85 were described as malagueta, and four were malaguetinha, a morphological type confirmed in this study. The typical morphological pattern of malagueta was described. Six similarity groups were established for C. frutescens based on the dendrogram and are discussed individually. The genetic variability analyzed in the study highlights the importance of characterizing genetic resources available for the development of new C. frutescens cultivars with the potential

The first set of EST resource for gene discovery and marker development in pigeonpea (Cajanus cajan L.

Directory of Open Access Journals (Sweden)

Byregowda Munishamappa

2010-03-01

.8% in molecular function. Further, 19 genes were identified differentially expressed between FW- responsive genotypes and 20 between SMD- responsive genotypes. Generated ESTs were compiled together with 908 ESTs available in public domain, at the time of analysis, and a set of 5,085 unigenes were defined that were used for identification of molecular markers in pigeonpea. For instance, 3,583 simple sequence repeat (SSR motifs were identified in 1,365 unigenes and 383 primer pairs were designed. Assessment of a set of 84 primer pairs on 40 elite pigeonpea lines showed polymorphism with 15 (28.8% markers with an average of four alleles per marker and an average polymorphic information content (PIC value of 0.40. Similarly, in silico mining of 133 contigs with ≥ 5 sequences detected 102 single nucleotide polymorphisms (SNPs in 37 contigs. As an example, a set of 10 contigs were used for confirming in silico predicted SNPs in a set of four genotypes using wet lab experiments. Occurrence of SNPs were confirmed for all the 6 contigs for which scorable and sequenceable amplicons were generated. PCR amplicons were not obtained in case of 4 contigs. Recognition sites for restriction enzymes were identified for 102 SNPs in 37 contigs that indicates possibility of assaying SNPs in 37 genes using cleaved amplified polymorphic sequences (CAPS assay. Conclusion The pigeonpea EST dataset generated here provides a transcriptomic resource for gene discovery and development of functional markers associated with biotic stress resistance. Sequence analyses of this dataset have showed conservation of a considerable number of pigeonpea transcripts across legume and model plant species analysed as well as some putative pigeonpea specific genes. Validation of identified biotic stress responsive genes should provide candidate genes for allele mining as well as candidate markers for molecular breeding.

Population structure revealed by different marker types (SSR or DArT) has an impact on the results of genome-wide association mapping in European barley cultivars

NARCIS (Netherlands)

Matthies, I.E.; Hintum, van T.J.L.; Weise, S.; Röder, M.S.

2012-01-01

Diversity arrays technology (DArT) and simple sequence repeat (SSR) markers were applied to investigate population structure, extent of linkage disequilibrium and genetic diversity (kinship) on a genome-wide level in European barley (Hordeum vulgare L.) cultivars. A set of 183 varieties could be

Irradiation facilities on the TRIGA-SSR thermal column

Energy Technology Data Exchange (ETDEWEB)

Roth, C; Aioanei, L; Preda, M; Gugiu, D [Institute for Nuclear Research, Pitesti (Romania); Garlea, I; Kelerman, C; Garlea, C [SENDRA ' Nuclear Technologies' ltd. Bucharest (Romania)

2004-07-01

The development of thermal and intermediate energy neutron irradiation facilities at the steady state core of the Romanian TRIGA Reactor is described. The reference thermal neutron irradiation facility consists of a dry spherical cavity placed into the graphite thermal column of the SSR core and the intermediate energy neutron irradiation facility is a {sigma}{sigma} system located into the thermal flux cavity. The implementation of the irradiation facilities into the under-water thermal column represented an important challenge from the standpoint of instrumentation solutions. The neutron flux and spectrum measurements were performed using foil activation techniques and fission rate measurements by sealed fission chambers, followed by spectrum unfolding procedure. The absolute fission reaction measurements, using calibrated fission chambers, allow the neutron flux density unit transfer from international reference neutron fields. The MCNP-4C code package was used for neutron spectrum computations in the thermal flux cavity and in the {sigma}{sigma} system. The neutron characterization program demonstrates the accuracy of the spectrum characteristics and neutron flux densities reported to the local monitoring system count rates. Some discrepancies, as compared to other similar facilities, were identified and discussed. These are caused by thermal column particularities: the presence of a water layer between the graphite cells (thermal neutron absorption) and smaller geometrical dimensions (neutron escape phenomena). Based on these results the metrological certification process, according to Romanian metrological laws requirements, is now in progress. (nevyjel)

Identification of SNP and SSR Markers in Finger Millet Using Next Generation Sequencing Technologies.

Science.gov (United States)

Gimode, Davis; Odeny, Damaris A; de Villiers, Etienne P; Wanyonyi, Solomon; Dida, Mathews M; Mneney, Emmarold E; Muchugi, Alice; Machuka, Jesse; de Villiers, Santie M

2016-01-01

Finger millet is an important cereal crop in eastern Africa and southern India with excellent grain storage quality and unique ability to thrive in extreme environmental conditions. Since negligible attention has been paid to improving this crop to date, the current study used Next Generation Sequencing (NGS) technologies to develop both Simple Sequence Repeat (SSR) and Single Nucleotide Polymorphism (SNP) markers. Genomic DNA from cultivated finger millet genotypes KNE755 and KNE796 was sequenced using both Roche 454 and Illumina technologies. Non-organelle sequencing reads were assembled into 207 Mbp representing approximately 13% of the finger millet genome. We identified 10,327 SSRs and 23,285 non-homeologous SNPs and tested 101 of each for polymorphism across a diverse set of wild and cultivated finger millet germplasm. For the 49 polymorphic SSRs, the mean polymorphism information content (PIC) was 0.42, ranging from 0.16 to 0.77. We also validated 92 SNP markers, 80 of which were polymorphic with a mean PIC of 0.29 across 30 wild and 59 cultivated accessions. Seventy-six of the 80 SNPs were polymorphic across 30 wild germplasm with a mean PIC of 0.30 while only 22 of the SNP markers showed polymorphism among the 59 cultivated accessions with an average PIC value of 0.15. Genetic diversity analysis using the polymorphic SNP markers revealed two major clusters; one of wild and another of cultivated accessions. Detailed STRUCTURE analysis confirmed this grouping pattern and further revealed 2 sub-populations within wild E. coracana subsp. africana. Both STRUCTURE and genetic diversity analysis assisted with the correct identification of the new germplasm collections. These polymorphic SSR and SNP markers are a significant addition to the existing 82 published SSRs, especially with regard to the previously reported low polymorphism levels in finger millet. Our results also reveal an unexploited finger millet genetic resource that can be included in the regional

Identification of SNP and SSR Markers in Finger Millet Using Next Generation Sequencing Technologies.

Directory of Open Access Journals (Sweden)

Davis Gimode

Full Text Available Finger millet is an important cereal crop in eastern Africa and southern India with excellent grain storage quality and unique ability to thrive in extreme environmental conditions. Since negligible attention has been paid to improving this crop to date, the current study used Next Generation Sequencing (NGS technologies to develop both Simple Sequence Repeat (SSR and Single Nucleotide Polymorphism (SNP markers. Genomic DNA from cultivated finger millet genotypes KNE755 and KNE796 was sequenced using both Roche 454 and Illumina technologies. Non-organelle sequencing reads were assembled into 207 Mbp representing approximately 13% of the finger millet genome. We identified 10,327 SSRs and 23,285 non-homeologous SNPs and tested 101 of each for polymorphism across a diverse set of wild and cultivated finger millet germplasm. For the 49 polymorphic SSRs, the mean polymorphism information content (PIC was 0.42, ranging from 0.16 to 0.77. We also validated 92 SNP markers, 80 of which were polymorphic with a mean PIC of 0.29 across 30 wild and 59 cultivated accessions. Seventy-six of the 80 SNPs were polymorphic across 30 wild germplasm with a mean PIC of 0.30 while only 22 of the SNP markers showed polymorphism among the 59 cultivated accessions with an average PIC value of 0.15. Genetic diversity analysis using the polymorphic SNP markers revealed two major clusters; one of wild and another of cultivated accessions. Detailed STRUCTURE analysis confirmed this grouping pattern and further revealed 2 sub-populations within wild E. coracana subsp. africana. Both STRUCTURE and genetic diversity analysis assisted with the correct identification of the new germplasm collections. These polymorphic SSR and SNP markers are a significant addition to the existing 82 published SSRs, especially with regard to the previously reported low polymorphism levels in finger millet. Our results also reveal an unexploited finger millet genetic resource that can be included

ConiferEST: an integrated bioinformatics system for data reprocessing and mining of conifer expressed sequence tags (ESTs).

Science.gov (United States)

Liang, Chun; Wang, Gang; Liu, Lin; Ji, Guoli; Fang, Lin; Liu, Yuansheng; Carter, Kikia; Webb, Jason S; Dean, Jeffrey F D

2007-05-29

With the advent of low-cost, high-throughput sequencing, the amount of public domain Expressed Sequence Tag (EST) sequence data available for both model and non-model organism is growing exponentially. While these data are widely used for characterizing various genomes, they also present a serious challenge for data quality control and validation due to their inherent deficiencies, particularly for species without genome sequences. ConiferEST is an integrated system for data reprocessing, visualization and mining of conifer ESTs. In its current release, Build 1.0, it houses 172,229 loblolly pine EST sequence reads, which were obtained from reprocessing raw DNA sequencer traces using our software--WebTraceMiner. The trace files were downloaded from NCBI Trace Archive. ConiferEST provides biologists unique, easy-to-use data visualization and mining tools for a variety of putative sequence features including cloning vector segments, adapter sequences, restriction endonuclease recognition sites, polyA and polyT runs, and their corresponding Phred quality values. Based on these putative features, verified sequence features such as 3' and/or 5' termini of cDNA inserts in either sense or non-sense strand have been identified in-silico. Interestingly, only 30.03% of the designated 3' ESTs were found to have an authenticated 5' terminus in the non-sense strand (i.e., polyT tails), while fewer than 5.34% of the designated 5' ESTs had a verified 5' terminus in the sense strand. Such previously ignored features provide valuable insight for data quality control and validation of error-prone ESTs, as well as the ability to identify novel functional motifs embedded in large EST datasets. We found that "double-termini adapters" were effective indicators of potential EST chimeras. For all sequences with in-silico verified termini/terminus, we used InterProScan to assign protein domain signatures, results of which are available for in-depth exploration using our biologist

ConiferEST: an integrated bioinformatics system for data reprocessing and mining of conifer expressed sequence tags (ESTs

Directory of Open Access Journals (Sweden)

Carter Kikia

2007-05-01

Full Text Available Abstract Background With the advent of low-cost, high-throughput sequencing, the amount of public domain Expressed Sequence Tag (EST sequence data available for both model and non-model organism is growing exponentially. While these data are widely used for characterizing various genomes, they also present a serious challenge for data quality control and validation due to their inherent deficiencies, particularly for species without genome sequences. Description ConiferEST is an integrated system for data reprocessing, visualization and mining of conifer ESTs. In its current release, Build 1.0, it houses 172,229 loblolly pine EST sequence reads, which were obtained from reprocessing raw DNA sequencer traces using our software – WebTraceMiner. The trace files were downloaded from NCBI Trace Archive. ConiferEST provides biologists unique, easy-to-use data visualization and mining tools for a variety of putative sequence features including cloning vector segments, adapter sequences, restriction endonuclease recognition sites, polyA and polyT runs, and their corresponding Phred quality values. Based on these putative features, verified sequence features such as 3' and/or 5' termini of cDNA inserts in either sense or non-sense strand have been identified in-silico. Interestingly, only 30.03% of the designated 3' ESTs were found to have an authenticated 5' terminus in the non-sense strand (i.e., polyT tails, while fewer than 5.34% of the designated 5' ESTs had a verified 5' terminus in the sense strand. Such previously ignored features provide valuable insight for data quality control and validation of error-prone ESTs, as well as the ability to identify novel functional motifs embedded in large EST datasets. We found that "double-termini adapters" were effective indicators of potential EST chimeras. For all sequences with in-silico verified termini/terminus, we used InterProScan to assign protein domain signatures, results of which are available

EST-derived SSR markers used as anchor loci for the construction of a consensus linkage map in ryegrass (Lolium spp.)

DEFF Research Database (Denmark)

Studer, Bruno; Kölliker, Roland; Muylle, Hilde

2010-01-01

Background Genetic markers and linkage mapping are basic prerequisites for marker-assisted selection and map-based cloning. In the case of the key grassland species Lolium spp., numerous mapping populations have been developed and characterised for various traits. Although some genetic linkage maps...

Development and characterization of EST-SSR markers for Artocarpus hypargyreus (Moraceae)1

Science.gov (United States)

Liu, Haijun; Tan, Weizheng; Sun, Hongbin; Liu, Yu; Meng, Kaikai; Liao, Wenbo

2016-01-01

Premise of the study: Polymorphic microsatellite markers were developed for Artocarpus hypargyreus (Moraceae), a threatened species endemic to China, to investigate the genetic diversity and structure of the species. Methods and Results: Based on the transcriptome data of A. hypargyreus, 63 primer pairs were preliminarily designed and tested, of which 34 were successfully amplified and 10 displayed clear polymorphisms across the 67 individuals from four populations of A. hypargyreus. The results showed the number of alleles per locus ranged from three to 10, and the observed heterozygosity and expected heterozygosity per locus varied from 0.000 to 0.706 and from 0.328 to 0.807, respectively. Conclusions: These microsatellite markers will be useful in exploring genetic diversity and structure of A. hypargyreus. Furthermore, most loci were successfully cross-amplified in A. nitidus and A. heterophyllus, indicating that they will be of great value for genetic study across this genus. PMID:28101438

Diversity of garlic (Allium sativum L.) using SSR, EST and AFLP markers

Science.gov (United States)

Germplasm from the center of origin/diversity is important for the breeding and fingerprinting crop plants. In this study we utilized both dominant and co-dominant markers for the characterization of garlic samples from diverse geographic origins to assess the relative utility of these markers to id...

Simple Sequence Repeat (SSR Genetic Linkage Map of D Genome Diploid Cotton Derived from an Interspecific Cross between Gossypium davidsonii and Gossypium klotzschianum

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Joy Nyangasi Kirungu

2018-01-01

Full Text Available The challenge in tetraploid cotton cultivars is the narrow genetic base and therefore, the bottleneck is how to obtain interspecific hybrids and introduce the germplasm directly from wild cotton to elite cultivars. Construction of genetic maps has provided insight into understanding the genome structure, interrelationships between organisms in relation to evolution, and discovery of genes that carry important agronomic traits in plants. In this study, we generated an interspecific hybrid between two wild diploid cottons, Gossypium davidsonii and Gossypium klotzschianum, and genotyped 188 F2:3 populations in order to develop a genetic map. We screened 12,560 SWU Simple Sequence Repeat (SSR primers and obtained 1000 polymorphic markers which accounted for only 8%. A total of 928 polymorphic primers were successfully scored and only 728 were effectively linked across the 13 chromosomes, but with an asymmetrical distribution. The map length was 1480.23 cM, with an average length of 2.182 cM between adjacent markers. A high percentage of the markers on the map developed, and for the physical map of G. raimondii, exhibited highly significant collinearity, with two types of duplication. High level of segregation distortion was observed. A total of 27 key genes were identified with diverse roles in plant hormone signaling, development, and defense reactions. The achievement of developing the F2:3 population and its genetic map constructions may be a landmark in establishing a new tool for the genetic improvement of cultivars from wild plants in cotton. Our map had an increased recombination length compared to other maps developed from other D genome cotton species.

Development of expressed sequence tag-simple sequence repeat markers for genetic characterization and population structure analysis of Praxelis clematidea (Asteraceae).

Science.gov (United States)

Wang, Q Z; Huang, M; Downie, S R; Chen, Z X

2016-05-23

Invasive plants tend to spread aggressively in new habitats and an understanding of their genetic diversity and population structure is useful for their management. In this study, expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed for the invasive plant species Praxelis clematidea (Asteraceae) from 5548 Stevia rebaudiana (Asteraceae) expressed sequence tags (ESTs). A total of 133 microsatellite-containing ESTs (2.4%) were identified, of which 56 (42.1%) were hexanucleotide repeat motifs and 50 (37.6%) were trinucleotide repeat motifs. Of the 24 primer pairs designed from these 133 ESTs, 7 (29.2%) resulted in significant polymorphisms. The number of alleles per locus ranged from 5 to 9. The relatively high genetic diversity (H = 0.2667, I = 0.4212, and P = 100%) of P. clematidea was related to high gene flow (Nm = 1.4996) among populations. The coefficient of population differentiation (GST = 0.2500) indicated that most genetic variation occurred within populations. A Mantel test suggested that there was significant correlation between genetic distance and geographical distribution (r = 0.3192, P = 0.012). These results further support the transferability of EST-SSR markers between closely related genera of the same family.

Development of simple sequence repeat (SSR) markers that are ...

African Journals Online (AJOL)

Simple sequence repeats (SSRs) markers were developed through data mining of 3,803 expressed sequence tags (ESTs) previously published. A total of 144 di- to penta-type SSRs were identified and they were screened for polymorphism between two turnip cultivars, 'Tsuda' and 'Yurugi Akamaru'. Out of 90 EST-SSRs for ...

Genome wide SSR high density genetic map construction from an interspecific cross of Gossypium hirsutum × Gossypium tomentosum

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Muhammad Kashif Riaz eKhan

2016-04-01

Full Text Available A high density genetic map was constructed using F2 population derived from an interspecific cross of G. hirsutum x G. tomentosum. The map consisted of 3,093 marker loci distributed across all the 26 chromosomes and covered 4,365.3 cM of cotton genome with an average inter-marker distance of 1.48 cM. The maximum length of chromosome was 218.38 cM and the minimum was 122.09 cM with an average length of 167.90 cM. A sub-genome covers more genetic distance (2,189.01 cM with an average inter loci distance of 1.53 cM than D sub-genome which covers a length of 2,176.29 cM with an average distance of 1.43 cM. There were 716 distorted loci in the map accounting for 23.14% and most distorted loci were distributed on D sub-genome (25.06%, which were more than on A sub-genome (21.23%. In our map 49 segregation hotspots (SDR were distributed across the genome with more on D sub-genome as compared to A genome. Two post-polyploidization reciprocal translocations of A2/A3 and A4/A5 were suggested by 7 pairs of duplicate loci. The map constructed through these studies is one of the three densest genetic maps in cotton however; this is the first dense genome wide SSR interspecific genetic map between G. hirsutum and G. tomentosum.

Evaluation of Advanced Chickpea (Cicer Arietinum L.) Accessions Based on Drought Tolerance Indices and SSR Markers Against Different Water Treatments

International Nuclear Information System (INIS)

Maqbool, M. A.; Aslam, M.

2016-01-01

Chickpea is mainly grown on marginal lands and encounter the problem of erratic rainfall that causes lack of water availability especially at terminal growth stages. Forty advanced chickpea genotypes were grown under irrigated, rainfed and tunnel conditions for two years (2012-13 and 2013-14). Data were collected for seed yield and analyzed by analysis of variance. Highly significant differences among genotypes and water treatments were observed for seed yield. However, across the year differences were insignificant for seed yield of chickpea. Seed yield under rainfed was higher than under irrigated conditions. Forty genotypes were assembled in four distinct groups on the basis of PCA biplot for different drought tolerance indices. These four distinct groups were representative of genotypic performance under normal and stressed conditions. Twenty eight SSR primers were used for sortation of genotypes either as drought tolerant or susceptible and to find association with results of drought tolerance indices. Only nine SSR markers were found to be polymorphic while others were either monomorphic or not amplified. H3DO5 and TA8 with Group-I, TR19 and ICCM0035 with Group-II, ICCM0035 with Group-III and TA25 was strongly correlated with results of Group-IV. Genotypes of group-I were drought tolerant whereas, CH16/06, CH81/06 and D097-11 within this groups were more tolerant. (author)

A SNP and SSR based genetic map of asparagus bean (Vigna. unguiculata ssp. sesquipedialis and comparison with the broader species.

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Pei Xu

Full Text Available Asparagus bean (Vigna. unguiculata ssp. sesquipedialis is a distinctive subspecies of cowpea [Vigna. unguiculata (L. Walp.] that apparently originated in East Asia and is characterized by extremely long and thin pods and an aggressive climbing growth habit. The crop is widely cultivated throughout Asia for the production of immature pods known as 'long beans' or 'asparagus beans'. While the genome of cowpea ssp. unguiculata has been characterized recently by high-density genetic mapping and partial sequencing, little is known about the genome of asparagus bean. We report here the first genetic map of asparagus bean based on SNP and SSR markers. The current map consists of 375 loci mapped onto 11 linkage groups (LGs, with 191 loci detected by SNP markers and 184 loci by SSR markers. The overall map length is 745 cM, with an average marker distance of 1.98 cM. There are four high marker-density blocks distributed on three LGs and three regions of segregation distortion (SDRs identified on two other LGs, two of which co-locate in chromosomal regions syntenic to SDRs in soybean. Synteny between asparagus bean and the model legume Lotus. japonica was also established. This work provides the basis for mapping and functional analysis of genes/QTLs of particular interest in asparagus bean, as well as for comparative genomics study of cowpea at the subspecies level.

A SNP and SSR Based Genetic Map of Asparagus Bean (Vigna. unguiculata ssp. sesquipedialis) and Comparison with the Broader Species

Science.gov (United States)

Xu, Pei; Wu, Xiaohua; Wang, Baogen; Liu, Yonghua; Ehlers, Jeffery D.; Close, Timothy J.; Roberts, Philip A.; Diop, Ndeye-Ndack; Qin, Dehui; Hu, Tingting; Lu, Zhongfu; Li, Guojing

2011-01-01

Asparagus bean (Vigna. unguiculata ssp. sesquipedialis) is a distinctive subspecies of cowpea [Vigna. unguiculata (L.) Walp.] that apparently originated in East Asia and is characterized by extremely long and thin pods and an aggressive climbing growth habit. The crop is widely cultivated throughout Asia for the production of immature pods known as ‘long beans’ or ‘asparagus beans’. While the genome of cowpea ssp. unguiculata has been characterized recently by high-density genetic mapping and partial sequencing, little is known about the genome of asparagus bean. We report here the first genetic map of asparagus bean based on SNP and SSR markers. The current map consists of 375 loci mapped onto 11 linkage groups (LGs), with 191 loci detected by SNP markers and 184 loci by SSR markers. The overall map length is 745 cM, with an average marker distance of 1.98 cM. There are four high marker-density blocks distributed on three LGs and three regions of segregation distortion (SDRs) identified on two other LGs, two of which co-locate in chromosomal regions syntenic to SDRs in soybean. Synteny between asparagus bean and the model legume Lotus. japonica was also established. This work provides the basis for mapping and functional analysis of genes/QTLs of particular interest in asparagus bean, as well as for comparative genomics study of cowpea at the subspecies level. PMID:21253606

Construction of genetic linkage map of the medicinal and ...

Indian Academy of Sciences (India)

semidwarf habit, more salt and drought tolerance, low in al- .... Designed, designed forward/reverse + RAPD and EST-SSR primer sequences investigated for use in genetic ..... cell biology, molecular regulation and metabolic engineering ap-.

Discovery and mapping of a new expressed sequence tag-single nucleotide polymorphism and simple sequence repeat panel for large-scale genetic studies and breeding of Theobroma cacao L.

Science.gov (United States)

Allegre, Mathilde; Argout, Xavier; Boccara, Michel; Fouet, Olivier; Roguet, Yolande; Bérard, Aurélie; Thévenin, Jean Marc; Chauveau, Aurélie; Rivallan, Ronan; Clement, Didier; Courtois, Brigitte; Gramacho, Karina; Boland-Augé, Anne; Tahi, Mathias; Umaharan, Pathmanathan; Brunel, Dominique; Lanaud, Claire

2012-01-01

Theobroma cacao is an economically important tree of several tropical countries. Its genetic improvement is essential to provide protection against major diseases and improve chocolate quality. We discovered and mapped new expressed sequence tag-single nucleotide polymorphism (EST-SNP) and simple sequence repeat (SSR) markers and constructed a high-density genetic map. By screening 149 650 ESTs, 5246 SNPs were detected in silico, of which 1536 corresponded to genes with a putative function, while 851 had a clear polymorphic pattern across a collection of genetic resources. In addition, 409 new SSR markers were detected on the Criollo genome. Lastly, 681 new EST-SNPs and 163 new SSRs were added to the pre-existing 418 co-dominant markers to construct a large consensus genetic map. This high-density map and the set of new genetic markers identified in this study are a milestone in cocoa genomics and for marker-assisted breeding. The data are available at http://tropgenedb.cirad.fr. PMID:22210604

Identification of QTLs Associated with Callogenesis and Embryogenesis in Oil Palm Using Genetic Linkage Maps Improved with SSR Markers

Science.gov (United States)

Ting, Ngoot-Chin; Jansen, Johannes; Nagappan, Jayanthi; Ishak, Zamzuri; Chin, Cheuk-Weng; Tan, Soon-Guan; Cheah, Suan-Choo; Singh, Rajinder

2013-01-01

Clonal reproduction of oil palm by means of tissue culture is a very inefficient process. Tissue culturability is known to be genotype dependent with some genotypes being more amenable to tissue culture than others. In this study, genetic linkage maps enriched with simple sequence repeat (SSR) markers were developed for dura (ENL48) and pisifera (ML161), the two fruit forms of oil palm, Elaeis guineensis. The SSR markers were mapped onto earlier reported parental maps based on amplified fragment length polymorphism (AFLP) and restriction fragment length polymorphism (RFLP) markers. The new linkage map of ENL48 contains 148 markers (33 AFLPs, 38 RFLPs and 77 SSRs) in 23 linkage groups (LGs), covering a total map length of 798.0 cM. The ML161 map contains 240 markers (50 AFLPs, 71 RFLPs and 119 SSRs) in 24 LGs covering a total of 1,328.1 cM. Using the improved maps, two quantitative trait loci (QTLs) associated with tissue culturability were identified each for callusing rate and embryogenesis rate. A QTL for callogenesis was identified in LGD4b of ENL48 and explained 17.5% of the phenotypic variation. For embryogenesis rate, a QTL was detected on LGP16b in ML161 and explained 20.1% of the variation. This study is the first attempt to identify QTL associated with tissue culture amenity in oil palm which is an important step towards understanding the molecular processes underlying clonal regeneration of oil palm. PMID:23382832

Genetic variation and comparison of orchardgrass (Dactylis glomerata L.) cultivars and wild accessions as revealed by SSR markers.

Science.gov (United States)

Xie, W G; Lu, X F; Zhang, X Q; Huang, L K; Cheng, L

2012-02-24

Orchardgrass is a highly variable, perennial forage grass that is cultivated throughout temperate and subtropical regions of the world. Despite its economic importance, the genetic relationship and distance among and within cultivars are largely unknown but would be of great interest for breeding programs. We investigated the molecular variation and structure of cultivar populations, compared the level of genetic diversity among cultivars (Baoxing, Anba, Bote, and Kaimo), subspecies (Dactylis glomerata ssp Woronowii) and advanced breeding line (YA02-116) to determine whether there is still sufficient genetic diversity within presently used cultivars for future breeding progress in China. Twenty individuals were analyzed from each of six accessions using SSR markers; 114 easily scored bands were generated from 15 SSR primer pairs, with an average of 7.6 alleles per locus. The polymorphic rate was 100% among the 120 individuals, reflecting a high degree of genetic diversity. Among the six accessions, the highest genetic diversity was observed in Kaimo (H = 0.2518; I = 0.3916; P = 87.3%) and 02-116 had a lower level of genetic diversity (H = 0.1806; I = 0.2788; P = 58.73%) compared with other cultivars tested. An of molecular variance revealed a much larger genetic variation within accessions (65%) than between them (35%). This observation suggests that these cultivars have potential for providing rich genetic resource for further breeding program. Furthermore, the study also indicated that Chinese orchardgrass breeding has involved strong selection for adaptation to forage production, which may result in restricted genetic base of orchardgrass cultivar.

Development of novel SSR markers for evaluation of genetic diversity and population structure in Tribulus terrestris L. (Zygophyllaceae).

Science.gov (United States)

Kaur, Kuljit; Sharma, Vikas; Singh, Vijay; Wani, Mohammad Saleem; Gupta, Raghbir Chand

2016-12-01

Tribulus terrestris L., commonly called puncture vine and gokhru, is an important member of Zygophyllaceae. The species is highly important in context to therapeutic uses and provides important active principles responsible for treatment of various diseases and also used as tonic. It is widely distributed in tropical regions of India and the world. However, status of its genetic diversity remained concealed due to lack of research work in this species. In present study, genetic diversity and structure of different populations of T. terrestris from north India was examined at molecular level using newly developed Simple Sequence Repeat (SSR) markers. In total, 20 primers produced 48 alleles in a size range of 100-500 bp with maximum (4) fragments amplified by TTMS-1, TTMS-25 and TTMS-33. Mean Polymorphism Information Content (PIC) and Marker Index (MI) were 0.368 and 1.01, respectively. Dendrogram showed three groups, one of which was purely containing accessions from Rajasthan while other two groups corresponded to Punjab and Haryana regions with intermixing of few other accessions. Analysis of molecular variance partitioned 76 % genetic variance within populations and 24 % among populations. Bayesian model based STRUCTURE analysis detected two genetic stocks for analyzed germplasm and also detected some admixed individuals. Different geographical populations of this species showed high level of genetic diversity. Results of present study can be useful in identifying diverse accessions and management of this plant resource. Moreover, the novel SSR markers developed can be utilized for various genetic analyses in this species in future.

Mining microsatellite markers from public expressed sequence tag ...

Indian Academy of Sciences (India)

2Shangqiu Vocational and Technical College, Shangqiu 476100, People's Republic of China .... Pomegranate EST data retrieval, assembly and SSR primer .... Single-letter abbreviation for the district of collection of the accessions: G, Gansu ...

Peculiarities of the contamination with radionuclides of the cultured pasture grass of the Lithuanian SSR after the Chernobyl accident

International Nuclear Information System (INIS)

Nedvetskajte, T.N.; Filistovich, V.I.; Petrulis, R.A.; Dauskurdis, S.I.; Tamulenajte, O.P.; Chias, K.V.

1989-01-01

Data on the contamination of pastures in the Lithuanian SSR with 131 I after the Chernobyl accident are given on the basis of measuring the grass samples from the cultured pastures. The predominant radionculides on the grass in the north-eastern and central parts of Lithuanie were 1 31 I and 103 Ru, while in its western and southern parts the 141 Ce, 144 Ce, 134 Cs, 137 Cs and other radioisotopes as well as hot particles predominated. The value of the grass-milk transfer coefficient was specified. 2 refs.; 5 figs

Ortodoncia estética invisible

OpenAIRE

Chávez Sevillano, Manuel Gustavo; Soldevilla Galarza, Luciano

2014-01-01

El adulto suele ofrecer resistencia a los convencionales tratamientos ortodóncicos, debido a la necesidad de llevar brackets visibles, tanto metálicos como estéticos de porcelana. El concepto de Ortodoncia Estética Invisible u Ortodoncia Lingual cubre las expectativas de este tipo de pacientes. La técnica multibrackets con aparatología lingual tiene aproximadamente 25 años de desarrollo y con la experiencia de los casos tratados, se ha llegado a la concepción de una técnica completamente prot...

Leaf margin phenotype-specific restriction-site-associated DNA-derived markers for pineapple (Ananas comosus L.).

Science.gov (United States)

Urasaki, Naoya; Goeku, Satoko; Kaneshima, Risa; Takamine, Tomonori; Tarora, Kazuhiko; Takeuchi, Makoto; Moromizato, Chie; Yonamine, Kaname; Hosaka, Fumiko; Terakami, Shingo; Matsumura, Hideo; Yamamoto, Toshiya; Shoda, Moriyuki

2015-06-01

To explore genome-wide DNA polymorphisms and identify DNA markers for leaf margin phenotypes, a restriction-site-associated DNA sequencing analysis was employed to analyze three bulked DNAs of F1 progeny from a cross between a 'piping-leaf-type' cultivar, 'Yugafu', and a 'spiny-tip-leaf-type' variety, 'Yonekura'. The parents were both Ananas comosus var. comosus. From the analysis, piping-leaf and spiny-tip-leaf gene-specific restriction-site-associated DNA sequencing tags were obtained and designated as PLSTs and STLSTs, respectively. The five PLSTs and two STSLTs were successfully converted to cleaved amplified polymorphic sequence (CAPS) or simple sequence repeat (SSR) markers using the sequence differences between alleles. Based on the genotyping of the F1 with two SSR and three CAPS markers, the five PLST markers were mapped in the vicinity of the P locus, with the closest marker, PLST1_SSR, being located 1.5 cM from the P locus. The two CAPS markers from STLST1 and STLST3 perfectly assessed the 'spiny-leaf type' as homozygotes of the recessive s allele of the S gene. The recombination value between the S locus and STLST loci was 2.4, and STLSTs were located 2.2 cM from the S locus. SSR and CAPS markers are applicable to marker-assisted selection of leaf margin phenotypes in pineapple breeding.

Expressed sequence tag-derived polymorphic SSR markers for Fucus serratus and amplification in other species of Fucus

NARCIS (Netherlands)

Coyer, J. A.; Hoarau, G.; Beszteri, B.; Pearson, G.; Olsen, J. L.

The seaweed genus Fucus is a dominant component of intertidal shores throughout the North Atlantic and North Pacific and has been the focus of considerable developmental, ecological, and evolutionary research for the past century. Here, we present details of 21 expressed sequence tag-derived simple

In silico characterization of microsatellites in Eucalyptus spp.: abundance, length variation and transposon associations

Directory of Open Access Journals (Sweden)

Edenilson Rabello

2005-01-01

Full Text Available This study assessed the abundance of microsatellites, or simple sequence repeats (SSR, in 19 Eucalyptus EST libraries from FORESTs, containing cDNA sequences from five species: E. grandis, E. globulus, E. saligna, E. urophylla and E. camaldulensis. Overall, a total of 11,534 SSRs and 8,447 SSR-containing sequences (25.5% of total ESTs were identified, with an average of 1 SSR/2.5 kb when considering all motifs and 1 SSR/3.1 kb when mononucleotides were not included. Dimeric repeats were the most abundant (41.03%, followed by trimerics (36.11% and monomerics (19.59%. The most frequent motifs were A/T (87.24% for monomerics, AG/CT (94.44% for dimerics, CCG/CGG (37.87% for trimerics, AAGG/CCTT (18.75% for tetramerics, AGAGG/CCTCT (14.04% for pentamerics and ACGGCG/CGCCGT (6.30% for hexamerics. According to sequence length, Class II or potentially variable markers were the most commonly found, followed by Class III. Two sequences presented high similarity to previously published Eucalyptus sequences from the NCBI database, EMBRA_72 and EMBRA_122. Local blastn search for transposons did not reveal the presence of any transposable elements with a cut-off value of 10-50. The large number of microsatellites identified will contribute to the refinement of marker-assisted mapping and to the discovery of novel markers for virtually all genes of economic interest.

EST Vocabulary Instruction

Directory of Open Access Journals (Sweden)

Célia D.S. Bell

2012-05-01

Full Text Available This study aims at contributing to the investigation on the instruction of EST (English for Science and Technology vocabulary, in terms of receptive use of the language. It evaluates the effectiveness of two teaching approaches to the acquisition of vocabulary. The first approach consisted of teaching vocabulary through the use of dictionaries, where the words were merely translated into the learners’ L1 or defined in the target language thus promoting superficial level of word processing. The second approach employed activities promoting deep level of word processing. Data were analysed quantitatively. Results indicated that the two approaches seem to have some equipotentiality, as far as EST vocabulary is concerned.

Association Analysis of Simple Sequence Repeat (SSR Markers with Agronomic Traits in Tall Fescue (Festuca arundinacea Schreb..

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Yanhong Lou

Full Text Available Tall fescue is widely used in temperate regions throughout the world as a dominant forage grass as well as a turfgrass, in pastoral and turf industry. However, the utilization of tall fescue was limited because of its leaf roughness, poor regeneration ability and poor stress resistance. New cultivars were desirable in modern pastoral industries exceed the potential of existing cultivars. Therefore, well understanding the agronomic traits and describing germplasms would help to overcome these constraints, and morphological evaluation of tall fescue germplasm is the key component in selecting rational parents for hybridization breeding. However, describing the morphological traits of tall fescue germplasm is costly and time-consuming. Fortunately, biotechnology approaches can supplement conventional breeding efforts for tall fescue improvement. Association mapping, as a powerful approach to identify association between agronomic traits and molecular markers has been widely used for enhancing the utilization, conservation and management of the tall fescue germplasms. Therefore, in the present research, 115 tall fescue accessions from different origins (25 accessions are cultivars; 31 accessions from America; 32 accessions from European; 7 accessions from Africa; 20 accessions from Asia, were evaluated for agronomic traits and genetic diversity with 90 simple sequence repeat (SSR markers. The panel displayed significant variation in spike count per plant (SCP and spike weight (SW. However, BCS performed the lowest CV among all the observed agronomic traits. Three subpopulations were identified within the collections but no obvious relative kinship (K was found. The GLM model was used to describe the association between SSR and agronomic traits. Fifty-one SSR markers associated with agronomic traits were observed. Twelve single-associated markers were associated with PH; six single-associated markers were associated with BCS; eight single

Genetic diversity and apple leaf spot disease resistance characterization assessed by SSR markers

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Gustavo H.F. Klabunde

2016-09-01

Full Text Available Among the cultivation problems of apple production in Brazil, Apple Leaf Spot (ALS disease represents one of the main breeding challenges. This study aims at analyzing the genetic diversity among 152 apple scion accessions available at the Apple Gene Bank of EPAGRI, located in Caçador, Santa Catarina/ Brazil. Eleven genomic SSR loci were analyzed to assess genetic diversity of ALS resistant and susceptible accessions. Results revealed high genetic diversity of the studied accessions, being 120 exclusive alleles (67 unique from scion accessions resistant to ALS, and a mean PIC of 0.823. The locus Probability of Identity (I ranged from 0.017 to 0.089. The combined I was 4.11 x 10-16, and the Power of Exclusion was 99.99999259%. In addition, the DNA fingerprint patterns will contribute as additional descriptors to select parental for crosses and early identification of apple accessions for breeding purposes, and also for cultivar protection.

Analysis of expressed sequence tags from Prunus mume flower and fruit and development of simple sequence repeat markers

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Gao Zhihong

2010-07-01

Full Text Available Abstract Background Expressed Sequence Tag (EST has been a cost-effective tool in molecular biology and represents an abundant valuable resource for genome annotation, gene expression, and comparative genomics in plants. Results In this study, we constructed a cDNA library of Prunus mume flower and fruit, sequenced 10,123 clones of the library, and obtained 8,656 expressed sequence tag (EST sequences with high quality. The ESTs were assembled into 4,473 unigenes composed of 1,492 contigs and 2,981 singletons and that have been deposited in NCBI (accession IDs: GW868575 - GW873047, among which 1,294 unique ESTs were with known or putative functions. Furthermore, we found 1,233 putative simple sequence repeats (SSRs in the P. mume unigene dataset. We randomly tested 42 pairs of PCR primers flanking potential SSRs, and 14 pairs were identified as true-to-type SSR loci and could amplify polymorphic bands from 20 individual plants of P. mume. We further used the 14 EST-SSR primer pairs to test the transferability on peach and plum. The result showed that nearly 89% of the primer pairs produced target PCR bands in the two species. A high level of marker polymorphism was observed in the plum species (65% and low in the peach (46%, and the clustering analysis of the three species indicated that these SSR markers were useful in the evaluation of genetic relationships and diversity between and within the Prunus species. Conclusions We have constructed the first cDNA library of P. mume flower and fruit, and our data provide sets of molecular biology resources for P. mume and other Prunus species. These resources will be useful for further study such as genome annotation, new gene discovery, gene functional analysis, molecular breeding, evolution and comparative genomics between Prunus species.

Sequence-based SSR marker development and their application in defining the Introgressions of LA0716 (Solanum pennellii in the background of cv. M82 (Solanum lycopersicum.

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Wenbo Long

Full Text Available The introgression lines (ILs from cv. M82 (Solanum lycopersicum × LA0716 (S. pennellii have been proven to be exceptionally useful for genetic analysis and gene cloning. The introgressions were originally defined by RFLP markers at their development. The objectives of this study are to develop polymorphic SSR markers, and to re-define the DNA introgression from LA0716 in the ILs. Tomato sequence data was scanned by software to generate SSR markers. In total, 829 SSRs, which could be robustly amplified by PCR, were developed. Among them, 658 SSRs were dinucleotide repeats, 162 were trinucleotide repeats, and nine were tetranucleotide repeats. The 829 SSRs together with 96 published RFLPs were integrated into the physical linkage map of S. lycopersicum. Introgressions of DNA fragments from LA0716 were re-defined among the 75 ILs using the newly developed SSRs. A specific introgression of DNA fragment from LA0716 was identified in 72 ILs as described previously by RFLP, whereas the specific DNA introgression described previously were not detected in the ILs LA4035, LA4059 and LA4091. The physical location of each investigated DNA introgression was finely determined by SSR mapping. Among the 72 ILs, eight ILs showed a shorter and three ILs (IL3-2, IL12-3 and IL12-3-1 revealed a longer DNA introgression than that framed by RFLPs. Furthermore, 54 previously undefined segments were found in 21 ILs, ranging from 1 to 11 DNA introgressions per IL. Generally, the newly developed SSRs provide additional markers for genetic studies of tomatoes, and the fine definition of DNA introgressions from LA0716 would facilitate the use of the ILs for genetic analysis and gene cloning.

Development of SSR Markers in Hickory (Carya cathayensis Sarg.) and Their Transferability to Other Species of Carya.

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Li, Juan; Zeng, Yanru; Shen, Dengfeng; Xia, Guohua; Huang, Yinzhi; Huang, Youjun; Chang, Jun; Huang, Jianqin; Wang, Zhengjia

2014-10-01

Hickory (Carya cathayensis Sarg.), an important nut-producing species in Southeastern China, has high economic value, but so far there has been no cultivar bred under species although it is mostly propagated by seeding and some elite individuals have been found. It has been found recently that this species has a certain rate of apomixis and poor knowledge of its genetic background has influenced development of a feasible breeding strategy. Here in this paper we first release SSR (Simple sequence repeat) markers developed in this species and their transferability to other three species of the same genus, Carya. A total of 311 pairs of SSR primers in hickory were developed based on sequenced cDNAs of a fruit development-associated cDNA library and RNA-seq data of developing female floral buds and could be used to distinguish hickory, C. hunanensis Cheng et R. H. Chang ex R. H. Chang et Lu, C. illinoensis K. Koch (pecan) and C. dabieshanensis M. C. Liu et Z. J. Li, but they were monomorphic in both hickory and C. hunanensis although multi-alleles have been identified in all the four species. There is a transferability rate of 63.02% observed between hickory and pecan and the markers can be applied to study genetic diversity of accessions in pecan. When used in C. dabieshanensis, it was revealed that C. dabieshanensis had the number of alleles per locus ranging from 2 to 4, observed heterozygosity from 0 to 0.6667 and expected heterozygosity from 0.333 to 0.8667, respectively, which supports the existence of C. dabieshanensis as a separate species different from hickory and indicates that there is potential for selection and breeding in this species.

Identification of QTLs associated with callogenesis and embryogenesis in oil palm using genetic linkage maps improved with SSR markers.

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Ngoot-Chin Ting

Full Text Available Clonal reproduction of oil palm by means of tissue culture is a very inefficient process. Tissue culturability is known to be genotype dependent with some genotypes being more amenable to tissue culture than others. In this study, genetic linkage maps enriched with simple sequence repeat (SSR markers were developed for dura (ENL48 and pisifera (ML161, the two fruit forms of oil palm, Elaeis guineensis. The SSR markers were mapped onto earlier reported parental maps based on amplified fragment length polymorphism (AFLP and restriction fragment length polymorphism (RFLP markers. The new linkage map of ENL48 contains 148 markers (33 AFLPs, 38 RFLPs and 77 SSRs in 23 linkage groups (LGs, covering a total map length of 798.0 cM. The ML161 map contains 240 markers (50 AFLPs, 71 RFLPs and 119 SSRs in 24 LGs covering a total of 1,328.1 cM. Using the improved maps, two quantitative trait loci (QTLs associated with tissue culturability were identified each for callusing rate and embryogenesis rate. A QTL for callogenesis was identified in LGD4b of ENL48 and explained 17.5% of the phenotypic variation. For embryogenesis rate, a QTL was detected on LGP16b in ML161 and explained 20.1% of the variation. This study is the first attempt to identify QTL associated with tissue culture amenity in oil palm which is an important step towards understanding the molecular processes underlying clonal regeneration of oil palm.

Unraveling the efficiency of RAPD and SSR markers in diversity analysis and population structure estimation in common bean.

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Zargar, Sajad Majeed; Farhat, Sufia; Mahajan, Reetika; Bhakhri, Ayushi; Sharma, Arjun

2016-01-01

Increase in food production viz-a-viz quality of food is important to feed the growing human population to attain food as well as nutritional security. The availability of diverse germplasm of any crop is an important genetic resource to mine the genes that may assist in attaining food as well as nutritional security. Here we used 15 RAPD and 23 SSR markers to elucidate diversity among 51 common bean genotypes mostly landraces collected from the Himalayan region of Jammu and Kashmir, India. We observed that both the markers are highly polymorphic. The discriminatory power of these markers was determined using various parameters like; percent polymorphism, PIC, resolving power and marker index. 15 RAPDs produced 171 polymorphic bands, while 23 SSRs produced 268 polymorphic bands. SSRs showed a higher PIC value (0.300) compared to RAPDs (0.243). Further the resolving power of SSRs was 5.241 compared to 3.86 for RAPDs. However, RAPDs showed a higher marker index (2.69) compared to SSRs (1.279) that may be attributed to their higher multiplex ratio. The dendrograms generated with hierarchical UPGMA cluster analysis grouped genotypes into two main clusters with various degrees of sub clustering within the cluster. Here we observed that both the marker systems showed comparable accuracy in grouping genotypes of common bean according to their area of cultivation. The model based STRUCTURE analysis using 15 RAPD and 23 SSR markers identified a population with 3 sub-populations which corresponds to distance based groupings. High level of genetic diversity was observed within the population. These findings have further implications in common bean breeding as well as conservation programs.

Developing new microsatellite markers in walnut (Juglans regia L.) from Juglans nigra genomic GA enriched library

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Hayat Topcu; Nergiz Coban; Keith Woeste; Mehmet Sutyemez; Salih. Kafkas

2015-01-01

We attempted to develop new polymorphic SSR primer pairs in walnut using sequences derived from Juglans nigra L. genomic enriched library with GA repeat. The designed 94 SSR primer pairs were subjected to gradient PCR in 12 walnut cultivars to determine their optimum annealing temperatures and to determine whether they produce bands. Then, the...

Genome survey of pistachio (Pistacia vera L.) by next generation sequencing: Development of novel SSR markers and genetic diversity in Pistacia species

OpenAIRE

Ziya Motalebipour, Elmira; Kafkas, Salih; Khodaeiaminjan, Mortaza; ?oban, Nergiz; G?zel, Hatice

2016-01-01

Background Pistachio (Pistacia vera L.) is one of the most important nut crops in the world. There are about 11 wild species in the genus Pistacia, and they have importance as rootstock seed sources for cultivated P. vera and forest trees. Published information on the pistachio genome is limited. Therefore, a genome survey is necessary to obtain knowledge on the genome structure of pistachio by next generation sequencing. Simple sequence repeat (SSR) markers are useful tools for germplasm cha...

Common cause failure data collection and analysis for safety-related components of TRIGA SSR-14MW Pitesti, Romania

International Nuclear Information System (INIS)

Radu, G.; Mladin, D.

2003-01-01

This paper presents a study performed on the set of common cause failures (CCF) of safety-related components of the research reactor TRIGA SSR-14 MW Pitesti. The data collected cover a period of 20 years, from 1979 to 2000. The sources of data are Shift Supervisor Reports, Work Authorizations, and Reactor Log Books. Events collected are analyzed by failure mode and degrees of failure. Qualitative analysis of root causes, coupling factors and corrective actions and quantitative analysis of CCF events are studied. The objective of this work is to develop qualitative insights in the nature of the reported events and to build a site-specific common cause events database. (author)

EST! best practices

Science.gov (United States)

2000-10-05

This booklet presents the eighteen winners in a competition for projects that promote environmentally sustainable transportation (EST). These range from car sharing to hydrogen fueled buses to public transit promotion campaign. Each project is presen...

Strengths and weaknesses of EST-based prediction of tissue-specific alternative splicing

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Vingron Martin

2004-09-01

Full Text Available Abstract Background Alternative splicing contributes significantly to the complexity of the human transcriptome and proteome. Computational prediction of alternative splice isoforms are usually based on EST sequences that also allow to approximate the expression pattern of the related transcripts. However, the limited number of tissues represented in the EST data as well as the different cDNA construction protocols may influence the predictive capacity of ESTs to unravel tissue-specifically expressed transcripts. Methods We predict tissue and tumor specific splice isoforms based on the genomic mapping (SpliceNest of the EST consensus sequences and library annotation provided in the GeneNest database. We further ascertain the potentially rare tissue specific transcripts as the ones represented only by ESTs derived from normalized libraries. A subset of the predicted tissue and tumor specific isoforms are then validated via RT-PCR experiments over a spectrum of 40 tissue types. Results Our strategy revealed 427 genes with at least one tissue specific transcript as well as 1120 genes showing tumor specific isoforms. While our experimental evaluation of computationally predicted tissue-specific isoforms revealed a high success rate in confirming the expression of these isoforms in the respective tissue, the strategy frequently failed to detect the expected restricted expression pattern. The analysis of putative lowly expressed transcripts using normalized cDNA libraries suggests that our ability to detect tissue-specific isoforms strongly depends on the expression level of the respective transcript as well as on the sensitivity of the experimental methods. Especially splice isoforms predicted to be disease-specific tend to represent transcripts that are expressed in a set of healthy tissues rather than novel isoforms. Conclusions We propose to combine the computational prediction of alternative splice isoforms with experimental validation for

Assessment of Genetic Diversity and Population Genetic Structure of Corylus mandshurica in China Using SSR Markers.

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Zong, Jian-Wei; Zhao, Tian-Tian; Ma, Qing-Hua; Liang, Li-Song; Wang, Gui-Xi

2015-01-01

Corylus mandshurica, also known as pilose hazelnut, is an economically and ecologically important species in China. In this study, ten polymorphic simple sequence repeat (SSR) markers were applied to evaluate the genetic diversity and population structure of 348 C. mandshurica individuals among 12 populations in China. The SSR markers expressed a relatively high level of genetic diversity (Na = 15.3, Ne = 5.6604, I = 1.8853, Ho = 0.6668, and He = 0.7777). According to the coefficient of genetic differentiation (Fst = 0.1215), genetic variation within the populations (87.85%) were remarkably higher than among populations (12.15%). The average gene flow (Nm = 1.8080) significantly impacts the genetic structure of C. mandshurica populations. The relatively high gene flow (Nm = 1.8080) among wild C. mandshurica may be caused by wind-pollinated flowers, highly nutritious seeds and self-incompatible mating system. The UPGMA (unweighted pair group method of arithmetic averages) dendrogram was divided into two main clusters. Moreover, the results of STRUCTURE analysis suggested that C. mandshurica populations fell into two main clusters. Comparison of the UPGMA dendrogram and the Bayesian STRUCTURE analysis showed general agreement between the population subdivisions and the genetic relationships among populations of C. mandshurica. Group I accessions were located in Northeast China, while Group II accessions were in North China. It is worth noting that a number of genetically similar populations were located in the same geographic region. The results further showed that there was obvious genetic differentiation among populations from Northeast China to North China. Results from the Mantel test showed a weak but still significant positive correlation between Nei's genetic distance and geographic distance (km) among populations (r = 0.419, P = 0.005), suggesting that genetic differentiation in the 12 C. mandshurica populations might be related to geographic distance. These

Assessment of Genetic Diversity and Population Genetic Structure of Corylus mandshurica in China Using SSR Markers.

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Jian-Wei Zong

Full Text Available Corylus mandshurica, also known as pilose hazelnut, is an economically and ecologically important species in China. In this study, ten polymorphic simple sequence repeat (SSR markers were applied to evaluate the genetic diversity and population structure of 348 C. mandshurica individuals among 12 populations in China. The SSR markers expressed a relatively high level of genetic diversity (Na = 15.3, Ne = 5.6604, I = 1.8853, Ho = 0.6668, and He = 0.7777. According to the coefficient of genetic differentiation (Fst = 0.1215, genetic variation within the populations (87.85% were remarkably higher than among populations (12.15%. The average gene flow (Nm = 1.8080 significantly impacts the genetic structure of C. mandshurica populations. The relatively high gene flow (Nm = 1.8080 among wild C. mandshurica may be caused by wind-pollinated flowers, highly nutritious seeds and self-incompatible mating system. The UPGMA (unweighted pair group method of arithmetic averages dendrogram was divided into two main clusters. Moreover, the results of STRUCTURE analysis suggested that C. mandshurica populations fell into two main clusters. Comparison of the UPGMA dendrogram and the Bayesian STRUCTURE analysis showed general agreement between the population subdivisions and the genetic relationships among populations of C. mandshurica. Group I accessions were located in Northeast China, while Group II accessions were in North China. It is worth noting that a number of genetically similar populations were located in the same geographic region. The results further showed that there was obvious genetic differentiation among populations from Northeast China to North China. Results from the Mantel test showed a weak but still significant positive correlation between Nei's genetic distance and geographic distance (km among populations (r = 0.419, P = 0.005, suggesting that genetic differentiation in the 12 C. mandshurica populations might be related to geographic

Identification of candidate genes for human pituitary development by EST analysis

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Xiao Huasheng

2009-03-01

Full Text Available Abstract Background The pituitary is a critical neuroendocrine gland that is comprised of five hormone-secreting cell types, which develops in tandem during the embryonic stage. Some essential genes have been identified in the early stage of adenohypophysial development, such as PITX1, FGF8, BMP4 and SF-1. However, it is likely that a large number of signaling molecules and transcription factors essential for determination and terminal differentiation of specific cell types remain unidentified. High-throughput methods such as microarray analysis may facilitate the measurement of gene transcriptional levels, while Expressed sequence tag (EST sequencing, an efficient method for gene discovery and expression level analysis, may no-redundantly help to understand gene expression patterns during development. Results A total of 9,271 ESTs were generated from both fetal and adult pituitaries, and assigned into 961 gene/EST clusters in fetal and 2,747 in adult pituitary by homology analysis. The transcription maps derived from these data indicated that developmentally relevant genes, such as Sox4, ST13 and ZNF185, were dominant in the cDNA library of fetal pituitary, while hormones and hormone-associated genes, such as GH1, GH2, POMC, LHβ, CHGA and CHGB, were dominant in adult pituitary. Furthermore, by using RT-PCR and in situ hybridization, Sox4 was found to be one of the main transcription factors expressed in fetal pituitary for the first time. It was expressed at least at E12.5, but decreased after E17.5. In addition, 40 novel ESTs were identified specifically in this tissue. Conclusion The significant changes in gene expression in both tissues suggest a distinct and dynamic switch between embryonic and adult pituitaries. All these data along with Sox4 should be confirmed to further understand the community of multiple signaling pathways that act as a cooperative network that regulates maturation of the pituitary. It was also suggested that EST

Assessment of genetic diversity, population structure and relationships in Indian and non-Indian genotypes of finger millet (Eleusine coracana (L.) Gaertn) using genomic SSR markers.

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Ramakrishnan, M; Antony Ceasar, S; Duraipandiyan, V; Al-Dhabi, N A; Ignacimuthu, S

2016-01-01

We evaluated the genetic variation and population structure in Indian and non-Indian genotypes of finger millet using 87 genomic SSR primers. The 128 finger millet genotypes were collected and genomic DNA was isolated. Eighty-seven genomic SSR primers with 60-70 % GC contents were used for PCR analysis of 128 finger millet genotypes. The PCR products were separated and visualized on a 6 % polyacrylamide gel followed by silver staining. The data were used to estimate major allele frequency using Power Marker v3.0. Dendrograms were constructed based on the Jaccard's similarity coefficient. Statistical fitness and population structure analyses were performed to find the genetic diversity. The mean major allele frequency was 0.92; the means of polymorphic alleles were 2.13 per primer and 1.45 per genotype; the average polymorphism was 59.94 % per primer and average PIC value was 0.44 per primer. Indian genotypes produced an additional 0.21 allele than non-Indian genotypes. Gene diversity was in the range from 0.02 to 0.35. The average heterozygosity was 0.11, close to 100 % homozygosity. The highest inbreeding coefficient was observed with SSR marker UGEP67. The Jaccard's similarity coefficient value ranged from 0.011 to 0.836. The highest similarity value was 0.836 between genotypes DPI009-04 and GPU-45. Indian genotypes were placed in Eleusine coracana major cluster (EcMC) 1 along with 6 non-Indian genotypes. AMOVA showed that molecular variance in genotypes from various geographical regions was 4 %; among populations it was 3 % and within populations it was 93 %. PCA scatter plot analysis showed that GPU-28, GPU-45 and DPI009-04 were closely dispersed in first component axis. In structural analysis, the genotypes were divided into three subpopulations (SP1, SP2 and SP3). All the three subpopulations had an admixture of alleles and no pure line was observed. These analyses confirmed that all the genotypes were genetically diverse and had been grouped based on

Biochemical and Structural Analysis of Hormone-sensitive Lipase Homolog EstE7: Insight into the Stabilized Dimerization of HSL-Homolog Proteins

International Nuclear Information System (INIS)

Nam, Ki Hyun; Park, Sung Ha; Lee, Won Ho; Hwang, Kwang Yeon

2010-01-01

Hormone sensitive lipase (HSL) plays a major role in energy homeostasis and lipid metabolism. Several crystal structures of HSL-homolog proteins have been identified, which has led to a better understanding of its molecular function. HSLhomolog proteins exit as both monomer and dimer, but the biochemical and structural basis for such oligomeric states has not been successfully elucidated. Therefore, we determined the crystal structure of HSL-homolog protein EstE7 from a metagenome library at 2.2 A resolution and characterized the oligomeric states of EstE7 both structurally and biochemically. EstE7 protein prefers the dimeric state in solution, which is supported by its higher enzymatic activity in the dimeric state. In the crystal form, EstE7 protein shows two-types of dimeric interface. Specifically, dimerization via the external β8-strand occurred through tight association between two pseudosymmetric folds via salt bridges, hydrogen bonds and van der Waals interactions. This dimer formation was similar to that of other HSL-homolog protein structures such as AFEST, BEFA, and EstE1. We anticipate that our results will provide insight into the oligomeric state of HSLhomolog proteins

Variation in sequences containing microsatellite motifs in the perennial biomass and forage grass, Phalaris arundinacea (Poaceae).

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Barth, Susanne; Jankowska, Marta Jolanta; Hodkinson, Trevor Roland; Vellani, Tia; Klaas, Manfred

2016-03-22

Forty three microsatellite markers were developed for further genetic characterisation of a forage and biomass grass crop, for which genomic resources are currently scarce. The microsatellite markers were developed from a normalized EST-SSR library. All of the 43 markers gave a clear banding pattern on 3% Metaphor agarose gels. Eight selected SSR markers were tested in detail for polymorphism across eleven DNA samples of large geographic distribution across Europe. The new set of 43 SSR markers will help future research to characterise the genetic structure and diversity of Phalaris arundinacea, with a potential to further understand its invasive character in North American wetlands, as well as aid in breeding work for desired biomass and forage traits. P. arundinacea is particularly valued in the northern latitude as a crop with high biomass potential, even more so on marginal lands.

New polymorphic microsatellite markers derived from hemocyte cDNA library of Manila clam Ruditapes philippinarum challenged by the protozoan parasite Perkinsus olseni

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Kang, Hyun-Sil; Hong, Hyun-Ki; Park, Kyung-Il; Cho, Moonjae; Youn, Seok-Hyun; Choi, Kwang-Sik

2017-03-01

Manila clam Ruditapes philippinarum is one of the most important benthic animals in the coastal north Pacific region, where clam populations have been mixed genetically through trade and aquaculture activities. Accordingly, identification of the genetically different clam populations has become one of the most important issues to manage interbreeding of the local and introduced clam populations. To identify genetically different populations of clam populations, we developed 11 expressed sequence tag (EST)-microsatellite loci (i.e., simple sequence repeat, SSR) from 1,128 clam hemocyte cDNA clones challenged by the protozoan parasite Perkinsus olseni. Genotype analysis using the markers developed in this study demonstrated that clams from a tidal flat on the west coast contained 6 to 19 alleles per locus, and a population from Jeju Island had 4 to 20 alleles per locus. The expected heterozygosity of the 2 clam populations ranged from 0.472 to 0.919 for clams from the west coast, and 0.494 to 0.919 for clams from Jeju Island, respectively. Among the 11 loci discovered in this study, 7 loci significantly deviated from the Hardy-Weinberg equilibrium after Bonferroni correction. The 5 loci developed in this study also successfully amplified the SSRs of R. variegatus, a clam species taxonomically very close to R. philippinarum, from Hong Kong and Jeju Island. We believe that the 11 novel polymorphic SSR developed in this study can be utilized successfully in Manila clam genetic diversity analysis, as well as in genetic discrimination of different clam populations.

Identification of QTLs for resistance to powdery mildew and SSR markers diagnostic for powdery mildew resistance genes in melon (Cucumis melo L.).

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Fukino, Nobuko; Ohara, Takayoshi; Monforte, Antonio J; Sugiyama, Mitsuhiro; Sakata, Yoshiteru; Kunihisa, Miyuki; Matsumoto, Satoru

2008-12-01

Powdery mildew caused by Podosphaera xanthii is an important foliar disease in melon. To find molecular markers for marker-assisted selection, we constructed a genetic linkage map of melon based on a population of 93 recombinant inbred lines derived from crosses between highly resistant AR 5 and susceptible 'Earl's Favourite (Harukei 3)'. The map spans 877 cM and consists of 167 markers, comprising 157 simple sequence repeats (SSRs), 7 sequence characterized amplified region/cleavage amplified polymorphic sequence markers and 3 phenotypic markers segregating into 20 linkage groups. Among them, 37 SSRs and 6 other markers were common to previous maps. Quantitative trait locus (QTL) analysis identified two loci for resistance to powdery mildew. The effects of these QTLs varied depending on strain and plant stage. The percentage of phenotypic variance explained for resistance to the pxA strain was similar between QTLs (R (2) = 22-28%). For resistance to pxB strain, the QTL on linkage group (LG) XII was responsible for much more of the variance (41-46%) than that on LG IIA (12-13%). The QTL on LG IIA was located between two SSR markers. Using an independent population, we demonstrated the effectiveness of these markers. This is the first report of universal and effective markers linked to a gene for powdery mildew resistance in melon.

Simple sequence repeat marker development from bacterial artificial chromosome end sequences and expressed sequence tags of flax (Linum usitatissimum L.).

Science.gov (United States)

Cloutier, Sylvie; Miranda, Evelyn; Ward, Kerry; Radovanovic, Natasa; Reimer, Elsa; Walichnowski, Andrzej; Datla, Raju; Rowland, Gordon; Duguid, Scott; Ragupathy, Raja

2012-08-01

Flax is an important oilseed crop in North America and is mostly grown as a fibre crop in Europe. As a self-pollinated diploid with a small estimated genome size of ~370 Mb, flax is well suited for fast progress in genomics. In the last few years, important genetic resources have been developed for this crop. Here, we describe the assessment and comparative analyses of 1,506 putative simple sequence repeats (SSRs) of which, 1,164 were derived from BAC-end sequences (BESs) and 342 from expressed sequence tags (ESTs). The SSRs were assessed on a panel of 16 flax accessions with 673 (58 %) and 145 (42 %) primer pairs being polymorphic in the BESs and ESTs, respectively. With 818 novel polymorphic SSR primer pairs reported in this study, the repertoire of available SSRs in flax has more than doubled from the combined total of 508 of all previous reports. Among nucleotide motifs, trinucleotides were the most abundant irrespective of the class, but dinucleotides were the most polymorphic. SSR length was also positively correlated with polymorphism. Two dinucleotide (AT/TA and AG/GA) and two trinucleotide (AAT/ATA/TAA and GAA/AGA/AAG) motifs and their iterations, different from those reported in many other crops, accounted for more than half of all the SSRs and were also more polymorphic (63.4 %) than the rest of the markers (42.7 %). This improved resource promises to be useful in genetic, quantitative trait loci (QTL) and association mapping as well as for anchoring the physical/genetic map with the whole genome shotgun reference sequence of flax.

Generation and analysis of blueberry transcriptome sequences from leaves, developing fruit, and flower buds from cold acclimation through deacclimation.

Science.gov (United States)

Rowland, Lisa J; Alkharouf, Nadim; Darwish, Omar; Ogden, Elizabeth L; Polashock, James J; Bassil, Nahla V; Main, Dorrie

2012-04-02

There has been increased consumption of blueberries in recent years fueled in part because of their many recognized health benefits. Blueberry fruit is very high in anthocyanins, which have been linked to improved night vision, prevention of macular degeneration, anti-cancer activity, and reduced risk of heart disease. Very few genomic resources have been available for blueberry, however. Further development of genomic resources like expressed sequence tags (ESTs), molecular markers, and genetic linkage maps could lead to more rapid genetic improvement. Marker-assisted selection could be used to combine traits for climatic adaptation with fruit and nutritional quality traits. Efforts to sequence the transcriptome of the commercial highbush blueberry (Vaccinium corymbosum) cultivar Bluecrop and use the sequences to identify genes associated with cold acclimation and fruit development and develop SSR markers for mapping studies are presented here. Transcriptome sequences were generated from blueberry fruit at different stages of development, flower buds at different stages of cold acclimation, and leaves by next-generation Roche 454 sequencing. Over 600,000 reads were assembled into approximately 15,000 contigs and 124,000 singletons. The assembled sequences were annotated and functionally mapped to Gene Ontology (GO) terms. Frequency of the most abundant sequences in each of the libraries was compared across all libraries to identify genes that are potentially differentially expressed during cold acclimation and fruit development. Real-time PCR was performed to confirm their differential expression patterns. Overall, 14 out of 17 of the genes examined had differential expression patterns similar to what was predicted from their reads alone. The assembled sequences were also mined for SSRs. From these sequences, 15,886 blueberry EST-SSR loci were identified. Primers were designed from 7,705 of the SSR-containing sequences with adequate flanking sequence. One hundred

Generation and analysis of blueberry transcriptome sequences from leaves, developing fruit, and flower buds from cold acclimation through deacclimation

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Rowland Lisa J

2012-04-01

Full Text Available Abstract Background There has been increased consumption of blueberries in recent years fueled in part because of their many recognized health benefits. Blueberry fruit is very high in anthocyanins, which have been linked to improved night vision, prevention of macular degeneration, anti-cancer activity, and reduced risk of heart disease. Very few genomic resources have been available for blueberry, however. Further development of genomic resources like expressed sequence tags (ESTs, molecular markers, and genetic linkage maps could lead to more rapid genetic improvement. Marker-assisted selection could be used to combine traits for climatic adaptation with fruit and nutritional quality traits. Results Efforts to sequence the transcriptome of the commercial highbush blueberry (Vaccinium corymbosum cultivar Bluecrop and use the sequences to identify genes associated with cold acclimation and fruit development and develop SSR markers for mapping studies are presented here. Transcriptome sequences were generated from blueberry fruit at different stages of development, flower buds at different stages of cold acclimation, and leaves by next-generation Roche 454 sequencing. Over 600,000 reads were assembled into approximately 15,000 contigs and 124,000 singletons. The assembled sequences were annotated and functionally mapped to Gene Ontology (GO terms. Frequency of the most abundant sequences in each of the libraries was compared across all libraries to identify genes that are potentially differentially expressed during cold acclimation and fruit development. Real-time PCR was performed to confirm their differential expression patterns. Overall, 14 out of 17 of the genes examined had differential expression patterns similar to what was predicted from their reads alone. The assembled sequences were also mined for SSRs. From these sequences, 15,886 blueberry EST-SSR loci were identified. Primers were designed from 7,705 of the SSR-containing sequences

Generation and analysis of blueberry transcriptome sequences from leaves, developing fruit, and flower buds from cold acclimation through deacclimation

Science.gov (United States)

2012-01-01

Background There has been increased consumption of blueberries in recent years fueled in part because of their many recognized health benefits. Blueberry fruit is very high in anthocyanins, which have been linked to improved night vision, prevention of macular degeneration, anti-cancer activity, and reduced risk of heart disease. Very few genomic resources have been available for blueberry, however. Further development of genomic resources like expressed sequence tags (ESTs), molecular markers, and genetic linkage maps could lead to more rapid genetic improvement. Marker-assisted selection could be used to combine traits for climatic adaptation with fruit and nutritional quality traits. Results Efforts to sequence the transcriptome of the commercial highbush blueberry (Vaccinium corymbosum) cultivar Bluecrop and use the sequences to identify genes associated with cold acclimation and fruit development and develop SSR markers for mapping studies are presented here. Transcriptome sequences were generated from blueberry fruit at different stages of development, flower buds at different stages of cold acclimation, and leaves by next-generation Roche 454 sequencing. Over 600,000 reads were assembled into approximately 15,000 contigs and 124,000 singletons. The assembled sequences were annotated and functionally mapped to Gene Ontology (GO) terms. Frequency of the most abundant sequences in each of the libraries was compared across all libraries to identify genes that are potentially differentially expressed during cold acclimation and fruit development. Real-time PCR was performed to confirm their differential expression patterns. Overall, 14 out of 17 of the genes examined had differential expression patterns similar to what was predicted from their reads alone. The assembled sequences were also mined for SSRs. From these sequences, 15,886 blueberry EST-SSR loci were identified. Primers were designed from 7,705 of the SSR-containing sequences with adequate flanking

¿Qué está pasando con el agua en el Valle de Aburrá (Medellín-Colombia)?

OpenAIRE

Insuasty Rodríguez, Alfonso

2016-01-01

Resumen. El presente artículo, derivado de investigación, presenta un primer avance de algunas preguntas que han surgido respecto del abastecimiento sostenible y real de agua para Medellín, su calidad y los negocios que circulan en torno a este preciado recurso, presenta este texto, algunos hallazgos que nos posibilitan generar algunas líneas de análisis, con el fin de aportar en el necesario debate público, al respecto. Abstract. This article, derived from a piece of research, pres...

Repressive Actions of the State Security Against True Orthodox Church Structures in the Ukrainian SSR (1944–1953

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Vedeneev Dmitrii

2016-04-01

Full Text Available In the article on the basis of unknown scientific community documents of the Soviet state security bodies provides an analysis of the objectives and key areas of operational work and repressive actions of the security services communities against True Orthodox Church (TOC in the Ukrainian SSR in 1944–1953. The characteristic of agent and operational developments NKGB–MGB–KGB of the USSR against the so-called «catacomb Church», as a form of religious and social protest against aggressive atheistic policy of the Communist authorities, infringement of the rights of believers. The basic forms and methods of intelligence and operational activities of the security organs, aimed at creating informer positions in the environment of the communities of the TOC, making the split in the ranks of the adepts of secret religious sects, the collection of «compromising material» as the basis for the application of harsh repressive measures against the movement of the TOC. The authors pay special attention to the organization and personnel of units of the NKGB–MGB–KGB, engaged, according to the terminology, «the struggle with the Church-sectarian counterrevolution» and «Church-monarchist underground», a leading representative of which was considered in the TOC, particularly active in Chernihiv, Sumy, and Kharkiv oblasts of the Ukrainian SSR and the Donbass, and also in the neighboring regions of the Russian black soil region and the North Caucasus. Given the author’s periodization of the development of the catacomb movement, highlights the historical conditions of its creation and release in the USSR. Through the prism of intelligence documents examines the liturgical aspect of the TOC, its governing structure, forms of secrecy and concealment from the prosecution authorities, the position of the catacomb members in relation to social life and social structure in the USSR.

Rediscovering medicinal plants' potential with OMICS: microsatellite survey in expressed sequence tags of eleven traditional plants with potent antidiabetic properties.

Science.gov (United States)

Sahu, Jagajjit; Sen, Priyabrata; Choudhury, Manabendra Dutta; Dehury, Budheswar; Barooah, Madhumita; Modi, Mahendra Kumar; Talukdar, Anupam Das

2014-05-01

Herbal medicines and traditionally used medicinal plants present an untapped potential for novel molecular target discovery using systems science and OMICS biotechnology driven strategies. Since up to 40% of the world's poor people have no access to government health services, traditional and folk medicines are often the only therapeutics available to them. In this vein, North East (NE) India is recognized for its rich bioresources. As part of the Indo-Burma hotspot, it is regarded as an epicenter of biodiversity for several plants having myriad traditional uses, including medicinal use. However, the improvement of these valuable bioresources through molecular breeding strategies, for example, using genic microsatellites or Simple Sequence Repeats (SSRs) or Expressed Sequence Tags (ESTs)-derived SSRs has not been fully utilized in large scale to date. In this study, we identified a total of 47,700 microsatellites from 109,609 ESTs of 11 medicinal plants (pineapple, papaya, noyontara, bitter orange, bermuda brass, ratalu, barbados nut, mango, mulberry, lotus, and guduchi) having proven antidiabetic properties. A total of 58,159 primer pairs were designed for the non-redundant 8060 SSR-positive ESTs and putative functions were assigned to 4483 unique contigs. Among the identified microsatellites, excluding mononucleotide repeats, di-/trinucleotides are predominant, among which repeat motifs of AG/CT and AAG/CTT were most abundant. Similarity search of SSR containing ESTs and antidiabetic gene sequences revealed 11 microsatellites linked to antidiabetic genes in five plants. GO term enrichment analysis revealed a total of 80 enriched GO terms widely distributed in 53 biological processes, 17 molecular functions, and 10 cellular components associated with the 11 markers. The present study therefore provides concrete insights into the frequency and distribution of SSRs in important medicinal resources. The microsatellite markers reported here markedly add to the genetic

Genetic Diversity in Jatropha curcas L. Assessed with SSR and SNP Markers

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Juan M. Montes

2014-08-01

Full Text Available Jatropha curcas L. (jatropha is an undomesticated plant that has recently received great attention for its utilization in biofuel production, rehabilitation of wasteland, and rural development. Knowledge of genetic diversity and marker-trait associations is urgently needed for the design of breeding strategies. The main goal of this study was to assess the genetic structure and diversity in jatropha germplasm with co-dominant markers (Simple Sequence Repeats (SSR and Single Nucleotide Polymorphism (SNP in a diverse, worldwide, germplasm panel of 70 accessions. We found a high level of homozygosis in the germplasm that does not correspond to the purely outcrossing mating system assumed to be present in jatropha. We hypothesize that the prevalent mating system of jatropha comprise a high level of self-fertilization and that the outcrossing rate is low. Genetic diversity in accessions from Central America and Mexico was higher than in accession from Africa, Asia, and South America. We identified makers associated with the presence of phorbol esters. We think that the utilization of molecular markers in breeding of jatropha will significantly accelerate the development of improved cultivars.

Turismo y estética formativa

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Clara Inés Sánchez Arciniegas

2002-11-01

Full Text Available ¿Existe alguna armonía entre el conocimiento y la estética? Sin duda alguna el hombre con conocimiento y sin virtud de la estética es un autómata; este necesita de las diferentes manifestaciones en las que se encuentra plasmada y necesita recordarlas continuamente. La estética como doctrina de conocimiento no es reciente, en el siglo xviii cuando por primera vez se define teóricamente hasta nuestros días en la Universidad actual. Esta última aparentemente menos evidente debido a las nuevas formas de aprendizaje con herramientas tecnológicas muy avanzadas y contraria a la imagen del universitario que hace dos siglos como complemento a su educación se distraía a través del Gran Tour, partida que tiene el turismo para fomentar el goce estético. ¿Cuál es entonces la relación entre distracción y formación? Se debe entonces reflexionar y comprender que el conocimiento interdisciplinario y la metodología debe procurar en los hombres actitudes adecuadas frente a la cultura y el arte a través del conocimiento.

Construction of a SSR-Based Genetic Map and Identification of QTLs for Catechins Content in Tea Plant (Camellia sinensis)

Science.gov (United States)

Ma, Chun-Lei; Wang, Xin-Chao; Jin, Ji-Qiang; Wang, Xue-Min; Chen, Liang

2014-01-01

Catechins are the most important bioactive compounds in tea, and have been demonstrated to possess a wide variety of pharmacological activities. To characterize quantitative trait loci (QTLs) for catechins content in the tender shoots of tea plant, we constructed a moderately saturated genetic map using 406 simple sequence repeat (SSR) markers, based on a pseudo-testcross population of 183 individuals derived from an intraspecific cross of two Camellia sinensis varieties with diverse catechins composition. The map consisted of fifteen linkage groups (LGs), corresponding to the haploid chromosome number of tea plant (2n = 2x = 30). The total map length was 1,143.5 cM, with an average locus spacing of 2.9 cM. A total of 25 QTLs associated with catechins content were identified over two measurement years. Of these, nine stable QTLs were validated across years, and clustered into four main chromosome regions on LG03, LG11, LG12 and LG15. The population variability explained by each QTL was predominantly at moderate-to-high levels and ranged from 2.4% to 71.0%, with an average of 17.7%. The total number of QTL for each trait varied from four to eight, while the total population variability explained by all QTLs for a trait ranged between 38.4% and 79.7%. This is the first report on the identification of QTL for catechins content in tea plant. The results of this study provide a foundation for further cloning and functional characterization of catechin QTLs for utilization in improvement of tea plant. PMID:24676054

PAVE: Program for assembling and viewing ESTs

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Bomhoff Matthew

2009-08-01

Full Text Available Abstract Background New sequencing technologies are rapidly emerging. Many laboratories are simultaneously working with the traditional Sanger ESTs and experimenting with ESTs generated by the 454 Life Science sequencers. Though Sanger ESTs have been used to generate contigs for many years, no program takes full advantage of the 5' and 3' mate-pair information, hence, many tentative transcripts are assembled into two separate contigs. The new 454 technology has the benefit of high-throughput expression profiling, but introduces time and space problems for assembling large contigs. Results The PAVE (Program for Assembling and Viewing ESTs assembler takes advantage of the 5' and 3' mate-pair information by requiring that the mate-pairs be assembled into the same contig and joined by n's if the two sub-contigs do not overlap. It handles the depth of 454 data sets by "burying" similar ESTs during assembly, which retains the expression level information while circumventing time and space problems. PAVE uses MegaBLAST for the clustering step and CAP3 for assembly, however it assembles incrementally to enforce the mate-pair constraint, bury ESTs, and reduce incorrect joins and splits. The PAVE data management system uses a MySQL database to store multiple libraries of ESTs along with their metadata; the management system allows multiple assemblies with variations on libraries and parameters. Analysis routines provide standard annotation for the contigs including a measure of differentially expressed genes across the libraries. A Java viewer program is provided for display and analysis of the results. Our results clearly show the benefit of using the PAVE assembler to explicitly use mate-pair information and bury ESTs for large contigs. Conclusion The PAVE assembler provides a software package for assembling Sanger and/or 454 ESTs. The assembly software, data management software, Java viewer and user's guide are freely available.

PAVE: program for assembling and viewing ESTs.

Science.gov (United States)

Soderlund, Carol; Johnson, Eric; Bomhoff, Matthew; Descour, Anne

2009-08-26

New sequencing technologies are rapidly emerging. Many laboratories are simultaneously working with the traditional Sanger ESTs and experimenting with ESTs generated by the 454 Life Science sequencers. Though Sanger ESTs have been used to generate contigs for many years, no program takes full advantage of the 5' and 3' mate-pair information, hence, many tentative transcripts are assembled into two separate contigs. The new 454 technology has the benefit of high-throughput expression profiling, but introduces time and space problems for assembling large contigs. The PAVE (Program for Assembling and Viewing ESTs) assembler takes advantage of the 5' and 3' mate-pair information by requiring that the mate-pairs be assembled into the same contig and joined by n's if the two sub-contigs do not overlap. It handles the depth of 454 data sets by "burying" similar ESTs during assembly, which retains the expression level information while circumventing time and space problems. PAVE uses MegaBLAST for the clustering step and CAP3 for assembly, however it assembles incrementally to enforce the mate-pair constraint, bury ESTs, and reduce incorrect joins and splits. The PAVE data management system uses a MySQL database to store multiple libraries of ESTs along with their metadata; the management system allows multiple assemblies with variations on libraries and parameters. Analysis routines provide standard annotation for the contigs including a measure of differentially expressed genes across the libraries. A Java viewer program is provided for display and analysis of the results. Our results clearly show the benefit of using the PAVE assembler to explicitly use mate-pair information and bury ESTs for large contigs. The PAVE assembler provides a software package for assembling Sanger and/or 454 ESTs. The assembly software, data management software, Java viewer and user's guide are freely available.

Journal of Genetics | Indian Academy of Sciences

Indian Academy of Sciences (India)

Construction of an EST-SSR-based interspecific transcriptome linkage map of fibre development in cotton. Chuanxiang Liu ... National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, Hubei, People's Republic of China ...

SNP-finding in pig mitochondrial ESTs

DEFF Research Database (Denmark)

Scheibye-Alsing, Karsten; Cirera Salicio, Susanna; Gilchrist, M.J.

2008-01-01

The Sino-Danish pig genome project produced 685 851 ESTs (Gorodkin et al. 2007), of which 41 499 originated from the mitochondrial genome. In this study, the mitochondrial ESTs were assembled, and 374 putative SNPs were found. Chromatograms for the ESTs containing SNPs were manually inspected, an......, and 112 total (52 non-synonymous) SNPs were found to be of high confidence (five of them are close to disease-causing SNPs in humans). Nine of the high-confidence SNPs were tested experimentally, and eight were confirmed. The SNPs can be accessed online at http://pigest.ku.dk/more.mito...

Los estándares de proyectos en la implementación de los estándares internacionales de información financiera

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Carlos Augusto Rincón-Soto

2014-01-01

Full Text Available La exigencia de la implementación de los estándares internacionales en información financiera está articulada a los términos de otros estándares internacionales, aunque no es una restricción adquirir los estándares contables sin integrar los otros estándares en Colombia, estos se acoplan de manera sistémica, en un apoyo integrador. Realizar una implementación adecuada, requiere de tomar estrategias razonables, este trabajo muestra como los estándares de proyectos ofrecen los fundamentos necesarios para dirigir y gestionar el montaje de un sistema de información contable integral, que incluya las diferentes necesidades de los usuarios.

El leviatán estético

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Jorge Peñuela

2011-05-01

Full Text Available En este ensayo exploro algunos argumentos de Hannah Arendt, con el fin de mostrar las razones que explican el odio que se manifestaba en las discusiones artísticas de comienzos del siglo XX, odio que persiste aún en muchos escenarios artísticos actuales. Con Arendt sostengo que este fenómeno no está superado, porque el odio es la herramienta que despliega el Capital, para amalgamar a todos los desheredados que ha creado. Contextualizo en la práctica artística colombiana el siguiente argumento de Arendt: el capitalismo creó una amalgama de frustrados sociales, políticos y estéticos que destruye la esfera pública como lugar para el acontecer de la política, amalgama que denominó populacho. Introduzco la categoría de populacho estético, para hablar del odio que ha animado las prácticas artísticas en Colombia desde 1940.

Exploring nervous system transcriptomes during embryogenesis and metamorphosis in Xenopus tropicalis using EST analysis

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Wegnez Maurice

2007-05-01

Full Text Available Abstract Background The western African clawed frog Xenopus tropicalis is an anuran amphibian species now used as model in vertebrate comparative genomics. It provides the same advantages as Xenopus laevis but is diploid and has a smaller genome of 1.7 Gbp. Therefore X. tropicalis is more amenable to systematic transcriptome surveys. We initiated a large-scale partial cDNA sequencing project to provide a functional genomics resource on genes expressed in the nervous system during early embryogenesis and metamorphosis in X. tropicalis. Results A gene index was defined and analysed after the collection of over 48,785 high quality sequences. These partial cDNA sequences were obtained from an embryonic head and retina library (30,272 sequences and from a metamorphic brain and spinal cord library (27,602 sequences. These ESTs are estimated to represent 9,693 transcripts derived from an estimated 6,000 genes. Comparison of these cDNA sequences with protein databases indicates that 46% contain their start codon. Further annotation included Gene Ontology functional classification, InterPro domain analysis, alternative splicing and non-coding RNA identification. Gene expression profiles were derived from EST counts and used to define transcripts specific to metamorphic stages of development. Moreover, these ESTs allowed identification of a set of 225 polymorphic microsatellites that can be used as genetic markers. Conclusion These cDNA sequences permit in silico cloning of numerous genes and will facilitate studies aimed at deciphering the roles of cognate genes expressed in the nervous system during neural development and metamorphosis. The genomic resources developed to study X. tropicalis biology will accelerate exploration of amphibian physiology and genetics. In particular, the model will facilitate analysis of key questions related to anuran embryogenesis and metamorphosis and its associated regulatory processes.

Radiosynthesis of 7-chloro-N, N-dimethyl-5-[11C] methyl-4-oxo-3-phenyl-3, 5-dihydro-4H pyridazino [4, 5-b]indole-1-acetamide, [11C]SSR180575, a novel radioligand for imaging the TSPO (peripheral benzodiazepine receptor) with PET

International Nuclear Information System (INIS)

Thominiaux, C.; Damont, A.L.; Kuhnast, B.; Demphel, St.; Le Helleix, St.; Chauveau, F.; Boutin, H.; Van Camp, N.; Boisgard, R.; Tavitian, B.; Dolle, F.; Boisnard, S.; Rivron, L.; Roy, S.; Allen, J.; Chauveau, F.; Boutin, H.; Van Camp, N.; Boisgard, R.; Tavitian, B.; Rooney, T.; Benavides, J.; Hantraye, Ph.

2010-01-01

SSR180575 (7-chloro-N, N, 5-trimethyl-4-oxo-3-phenyl-3, 5-dihydro-4H-pyridazino [4, 5-b]indole-1-acetamide) is the lead compound of an original pyridazino-indole series of potent and highly selective TSPO (peripheral benzodiazepine receptor) ligands. Isotopic labeling of SSR180575 with the short-lived positron-emitter carbon-11 (T1/2: 20.38 min) at its 5-methyl-pyridazino[4, 5-b]indole moiety as well as at its N, N-dimethylacetamide function by methylation of the corresponding nor-analogues was investigated. Best results in terms of radiochemical yields and purities were obtained for the preparation of [indole-N-methyl- 11 C]SSR180575, where routine production batches of 4.5-5.0 GBq of radiochemically pure (499%) i.v. injectable solutions (specific radioactivities: 50-90 GBq/μmol) could be prepared within a total synthesis time of 25 min (HPLC purification included) starting from a 55 GBq [ 11 C]CO 2 cyclotron production batch (non decay-corrected overall radiochemical yields: 8-9%). The process comprises (1) trapping at -10 C of [ 11 C]methyl triflate in DMF (300 μl) containing 0.2-0.3 mg of the indole precursor for labeling and 4 mg of K 2 CO 3 (excess); (2) heating at 120 C for 3 min; (3) dilution of the residue with 0.5 ml of the HPLC mobile phase and (4) purification using semi-preparative reversed phase HPLC (Zorbax R SB-C-18). In vivo pharmacological properties of [indole-N-methyl- 11 C]SSR180575 as a candidate for imaging neuro-inflammation with positron emission tomography are currently evaluated. (authors)

EST Express: PHP/MySQL based automated annotation of ESTs from expression libraries.

Science.gov (United States)

Smith, Robin P; Buchser, William J; Lemmon, Marcus B; Pardinas, Jose R; Bixby, John L; Lemmon, Vance P

2008-04-10

Several biological techniques result in the acquisition of functional sets of cDNAs that must be sequenced and analyzed. The emergence of redundant databases such as UniGene and centralized annotation engines such as Entrez Gene has allowed the development of software that can analyze a great number of sequences in a matter of seconds. We have developed "EST Express", a suite of analytical tools that identify and annotate ESTs originating from specific mRNA populations. The software consists of a user-friendly GUI powered by PHP and MySQL that allows for online collaboration between researchers and continuity with UniGene, Entrez Gene and RefSeq. Two key features of the software include a novel, simplified Entrez Gene parser and tools to manage cDNA library sequencing projects. We have tested the software on a large data set (2,016 samples) produced by subtractive hybridization. EST Express is an open-source, cross-platform web server application that imports sequences from cDNA libraries, such as those generated through subtractive hybridization or yeast two-hybrid screens. It then provides several layers of annotation based on Entrez Gene and RefSeq to allow the user to highlight useful genes and manage cDNA library projects.

EST Express: PHP/MySQL based automated annotation of ESTs from expression libraries

Directory of Open Access Journals (Sweden)

Pardinas Jose R

2008-04-01

Full Text Available Abstract Background Several biological techniques result in the acquisition of functional sets of cDNAs that must be sequenced and analyzed. The emergence of redundant databases such as UniGene and centralized annotation engines such as Entrez Gene has allowed the development of software that can analyze a great number of sequences in a matter of seconds. Results We have developed "EST Express", a suite of analytical tools that identify and annotate ESTs originating from specific mRNA populations. The software consists of a user-friendly GUI powered by PHP and MySQL that allows for online collaboration between researchers and continuity with UniGene, Entrez Gene and RefSeq. Two key features of the software include a novel, simplified Entrez Gene parser and tools to manage cDNA library sequencing projects. We have tested the software on a large data set (2,016 samples produced by subtractive hybridization. Conclusion EST Express is an open-source, cross-platform web server application that imports sequences from cDNA libraries, such as those generated through subtractive hybridization or yeast two-hybrid screens. It then provides several layers of annotation based on Entrez Gene and RefSeq to allow the user to highlight useful genes and manage cDNA library projects.

Discrimination of candidate subgenome-specific loci by linkage map construction with an S1 population of octoploid strawberry (Fragaria × ananassa).

Science.gov (United States)

Nagano, Soichiro; Shirasawa, Kenta; Hirakawa, Hideki; Maeda, Fumi; Ishikawa, Masami; Isobe, Sachiko N

2017-05-12

The strawberry, Fragaria × ananassa, is an allo-octoploid (2n = 8x = 56) and outcrossing species. Although it is the most widely consumed berry crop in the world, its complex genome structure has hindered its genetic and genomic analysis, and thus discrimination of subgenome-specific loci among the homoeologous chromosomes is needed. In the present study, we identified candidate subgenome-specific single nucleotide polymorphism (SNP) and simple sequence repeat (SSR) loci, and constructed a linkage map using an S 1 mapping population of the cultivar 'Reikou' with an IStraw90 Axiom® SNP array and previously published SSR markers. The 'Reikou' linkage map consisted of 11,574 loci (11,002 SNPs and 572 SSR loci) spanning 2816.5 cM of 31 linkage groups. The 11,574 loci were located on 4738 unique positions (bin) on the linkage map. Of the mapped loci, 8999 (8588 SNPs and 411 SSR loci) showed a 1:2:1 segregation ratio of AA:AB:BB allele, which suggested the possibility of deriving loci from candidate subgenome-specific sequences. In addition, 2575 loci (2414 SNPs and 161 SSR loci) showed a 3:1 segregation of AB:BB allele, indicating they were derived from homoeologous genomic sequences. Comparative analysis of the homoeologous linkage groups revealed differences in genome structure among the subgenomes. Our results suggest that candidate subgenome-specific loci are randomly located across the genomes, and that there are small- to large-scale structural variations among the subgenomes. The mapped SNPs and SSR loci on the linkage map are expected to be seed points for the construction of pseudomolecules in the octoploid strawberry.