European and Asian Pears: Simple Sequence Repeat–Polyacrylamide Gel Electrophoresis-based Analysis of Commercially Important North American Cultivars

The genus Pyrus (pear) includes species and cultivars of great diversity. We have tested the feasibility of a polyacrylamide gel eletrophoresis (PAGE)-based +/– simple sequence repeat (SSR) screen as a means of defining relationships amongst pears of commercial importance in North America. The screen included 28 pear accessions, including economically important cultivars, numbered selections from breeding programs and interspecific hybrids. It relied on 18 SSR primer pairs, each of which produced polymorphic banding patterns in all the genotypes examined. Fragments were scored for presence or absence within genotypes. The results show that amplification and analysis of a small number of SSR loci enable identification of cultivars and reasonable definition of genetic relationships in North American pears. Seven primer pairs were sufficient to distinguish the 28 pear cultivars. Analyses using both distance and parsimony criteria grouped cultivars in a manner consistent with known pedigrees and sites of origin.

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Simple Sequence Repeat Marker Analysis of Genetic Relationships within Hydrangea macrophylla

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.132.3.341 ◽

2007 ◽

Vol 132 (3) ◽

pp. 341-351 ◽

Cited By ~ 12

Author(s):

Sandra M. Reed ◽

Timothy A. Rinehart

Keyword(s):

Genetic Diversity ◽

Simple Sequence Repeat ◽

Genetic Relationships ◽

Allelic Diversity ◽

Sequence Repeat ◽

Hydrangea Macrophylla ◽

Total Genetic Diversity ◽

Ssr Loci ◽

Diversity Studies ◽

Simple Sequence

Genetic diversity studies using 39 simple-sequence repeat (SSR) markers were carried out with 114 taxa of Hydrangea macrophylla (Thunb.) Ser., including 87 H. macrophylla ssp. macrophylla cultivars and 20 members of H. macrophylla ssp. serrata (Thunb.) Makino. The SSR loci were highly variable among the taxa, producing a mean of 8.26 alleles per locus. Overall allelic richness was relatively high at 5.12 alleles per locus. H. macrophylla ssp. serrata contained nearly twice the allelic diversity of H. macrophylla ssp. macrophylla. The majority of genetic diversity was found to reside within the subspecies, with only 12% of the total genetic diversity observed occurring between subspecies. Although the elevation of H. macrophylla ssp. serrata to species level has recently been recommended by several hydrangea authorities, these data support the subspecies designation. Four cultivars (Preziosa, Pink Beauty, Tokyo Delight, and Blue Deckle) appeared to be hybrids between the two subspecies. Genetic similarities were found among five remontant cultivars (Bailmer, Oak Hill, David Ramsey, Decatur Blue, and Penny Mac) and several nonremontant cultivars, including General Vicomtesse de Vibraye, Nikko Blue, All Summer Beauty, and La France. No close genetic relationship was found between the remontant cultivar Early Sensation and other remontant cultivars. Genetic similarities were found among variegated and double-flower cultivars. Within H. macrophylla ssp. macrophylla, cultivars with mophead inflorescences clustered separately from most lacecap cultivars. This indicates the cultivars with lacecap inflorescences that were among some of the earliest introductions to Europe were not widely used in the breeding of mophead forms. Some presumed synonyms were found to be valid (‘Preziosa’ and ‘Pink Beauty’, ‘Rosalba’ and ‘Benigaku’, ‘Geoffrey Chadbund’ and ‘Mowe’), whereas others were not (‘Harlequin’ and ‘Monrey’, ‘Nigra’ and ‘Mandschurica’). This study identified potentially unexploited sources of germplasm within H. macrophylla and relationships between existing cultivars of this popular shrub. This information should be of value when selecting parents for breeding programs.

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Simple Sequence Repeat and S-Locus Genotyping to Assist the Genetic Characterization and Breeding of Polyploid Prunus Species, P. spinosa and P. domestica subsp. insititia

Biochemical Genetics ◽

10.1007/s10528-021-10090-7 ◽

2021 ◽

Author(s):

Júlia Halász ◽

Noémi Makovics-Zsohár ◽

Ferenc Szőke ◽

Sezai Ercisli ◽

Attila Hegedűs

Keyword(s):

Simple Sequence Repeat ◽

Principal Component ◽

Sequence Repeat ◽

Breeding Programs ◽

Allele Number ◽

Genetic Potential ◽

Ssr Loci ◽

High Level ◽

Diversity Studies ◽

Simple Sequence

AbstractPolyploid Prunus spinosa (2n = 4 ×) and P. domestica subsp. insititia (2n = 6 ×) represent enormous genetic potential in Central Europe, which can be exploited in breeding programs. In Hungary, 16 cultivar candidates and a recognized cultivar ‘Zempléni’ were selected from wild-growing populations including ten P. spinosa, four P. domestica subsp. insititia and three P. spinosa × P. domestica hybrids (2n = 5 ×) were also created. Genotyping in eleven simple sequence repeat (SSR) loci and the multiallelic S-locus was used to characterize genetic variability and achieve a reliable identification of tested accessions. Nine SSR loci proved to be polymorphic and eight of those were highly informative (PIC values ˃ 0.7). A total of 129 SSR alleles were identified, which means 14.3 average allele number per locus and all accessions but two clones could be discriminated based on unique SSR fingerprints. A total of 23 S-RNase alleles were identified and the complete and partial S-genotype was determined for 10 and 7 accessions, respectively. The DNA sequence was determined for a total of 17 fragments representing 11 S-RNase alleles. ‘Zempléni’ was confirmed to be self-compatible carrying at least one non-functional S-RNase allele (SJ). Our results indicate that the S-allele pools of wild-growing P. spinosa and P. domestica subsp. insititia are overlapping in Hungary. Phylogenetic and principal component analyses confirmed the high level of diversity and genetic differentiation present within the analysed accessions and indicated putative ancestor–descendant relationships. Our data confirm that S-locus genotyping is suitable for diversity studies in polyploid Prunus species but non-related accessions sharing common S-alleles may distort phylogenetic inferences.

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Genotyping of Peach and Nectarine Cultivars with SSR and SRAP Molecular Markers

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.129.2.0204 ◽

2004 ◽

Vol 129 (2) ◽

pp. 204-210 ◽

Cited By ~ 37

Author(s):

Riaz Ahmad ◽

Dan Potter ◽

Stephen M. Southwick

Keyword(s):

Molecular Markers ◽

Ssr Markers ◽

Simple Sequence Repeat ◽

Sweet Cherry ◽

Prunus Persica ◽

Sequence Repeat ◽

Srap Markers ◽

Upgma Cluster Analysis ◽

Commercially Important ◽

Simple Sequence

Simple sequence repeat (SSR) and sequence related amplified polymorphism (SRAP) molecular markers were evaluated for detecting intraspecific variation in 38 commercially important peach and nectarine (Prunus persica) cultivars. Out of the 20 SSR primer pairs 17 were previously developed in sweet cherry and three in peach. The number of putative alleles revealed by SSR primer pairs ranged from one to five showing a low level of genetic variability among these cultivars. The average number of alleles per locus was 2.2. About 76% of cherry primers produced amplification products in peach and nectarine, showing a congeneric relationship within Prunus species. Only nine cultivars out of the 38 cultivars could be uniquely identified by the SSR markers. For SRAP, the number of fragments produced was highly variable, ranging from 10 to 33 with an average of 21.8 per primer combination. Ten primer combinations resulted in 49 polymorphic fragments in this closely related set of peaches and nectarines. Thirty out of the 38 peach and nectarine cultivars were identified by unique SRAP fingerprints. UPGMA Cluster analysis based on the SSR and SRAP polymorphic fragments was performed; the relationships inferred are discussed with reference to the pomological characteristics and pedigree of these cultivars. The results indicated that SSR and SRAP markers can be used to distinguish the genetically very close peach and nectarine cultivars as a complement to traditional pomological studies. However, for fingerprinting, SRAP markers appear to be much more effective, quicker and less expensive to develop than are SSR markers.

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Determination of genetic relationships among elite thermosensitive genic male sterile lines (TGMS) of rice (Oryza sativa L.) employing morphological and simple sequence repeat (SSR) markers

Journal of Genetics ◽

10.1007/s12041-011-0018-5 ◽

2011 ◽

Vol 90 (1) ◽

pp. 11-19 ◽

Cited By ~ 8

Author(s):

VIKAS KUMAR SINGH ◽

PRITI UPADHYAY ◽

PALLAVI SINHA ◽

ASHISH KUMAR MALL ◽

SANJAY KUMAR JAISWAL ◽

...

Keyword(s):

Oryza Sativa ◽

Ssr Markers ◽

Simple Sequence Repeat ◽

Oryza Sativa L ◽

Genetic Relationships ◽

Sequence Repeat ◽

Male Sterile ◽

Simple Sequence

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Analysis of genetic relationships and identification of lily cultivars based on inter-simple sequence repeat markers

Genetics and Molecular Research ◽

10.4238/2014.july.29.5 ◽

2014 ◽

Vol 13 (3) ◽

pp. 5778-5786 ◽

Cited By ~ 3

Author(s):

G.F. Cui ◽

L.F. Wu ◽

X.N. Wang ◽

W.J. Jia ◽

Q. Duan ◽

...

Keyword(s):

Simple Sequence Repeat ◽

Genetic Relationships ◽

Inter Simple Sequence Repeat ◽

Sequence Repeat ◽

Simple Sequence Repeat Markers ◽

Simple Sequence

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Evaluation of Genetic Diversity and Pedigree within Crapemyrtle Cultivars Using Simple Sequence Repeat Markers

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.136.2.116 ◽

2011 ◽

Vol 136 (2) ◽

pp. 116-128 ◽

Cited By ~ 14

Author(s):

Xinwang Wang ◽

Phillip A. Wadl ◽

Cecil Pounders ◽

Robert N. Trigiano ◽

Raul I. Cabrera ◽

...

Keyword(s):

Genetic Diversity ◽

Simple Sequence Repeat ◽

Interspecific Hybrids ◽

Size Variation ◽

Sequence Repeat ◽

Allele Size ◽

Low Genetic Diversity ◽

Ssr Loci ◽

Diversity Estimates ◽

Simple Sequence

Genetic diversity was estimated for 51 Lagerstroemia indica L. cultivars, five Lagerstroemia fauriei Koehne cultivars, and 37 interspecific hybrids using 78 simple sequence repeat (SSR) markers. SSR loci were highly variable among the cultivars, detecting an average of 6.6 alleles (amplicons) per locus. Each locus detected 13.6 genotypes on average. Cluster analysis identified three main groups that consisted of individual cultivars from L. indica, L. fauriei, and their interspecific hybrids. However, only 18.1% of the overall variation was the result of differences between these groups, which may be attributable to pedigree-based breeding strategies that use current cultivars as parents for future selections. Clustering within each group generally reflected breeding pedigrees but was not supported by bootstrap replicates. Low statistical support was likely the result of low genetic diversity estimates, which indicated that only 25.5% of the total allele size variation was attributable to differences between the species L. indica and L. fauriei. Most allele size variation, or 74.5%, was common to L. indica and L. fauriei. Thus, introgression of other Lagestroemia species such as Lagestroemia limii Merr. (L. chekiangensis Cheng), Lagestroemia speciosa (L.) Pers., and Lagestroemia subcostata Koehne may significantly expand crapemyrtle breeding programs. This study verified relationships between existing cultivars and identified potentially untapped sources of germplasm.

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Genetic diversity among silkworm (Bombyx mori L., Lep., Bombycidae) germplasms revealed by microsatellites

Genome ◽

10.1139/g05-053 ◽

2005 ◽

Vol 48 (5) ◽

pp. 802-810 ◽

Cited By ~ 30

Author(s):

Muwang Li ◽

Li Shen ◽

Anying Xu ◽

Xuexia Miao ◽

Chengxiang Hou ◽

...

Keyword(s):

Genetic Diversity ◽

Bombyx Mori ◽

Ssr Markers ◽

Simple Sequence Repeat ◽

Genetic Relationships ◽

Group Method ◽

Sequence Repeat ◽

Bombyx Mori L ◽

Simple Sequence ◽

Silkworm Bombyx Mori

To determine genetic relationships among strains of silkworm, Bombyx mori L., 31 strains with different origins, number of generations per year, number of molts per generation, and morphological characters were studied using simple sequence repeat (SSR) markers. Twenty-six primer pairs flanking microsatellite sequences in the silkworm genome were assayed. All were polymorphic and unambiguously separated silkworm strains from each other. A total of 188 alleles were detected with a mean value of 7.2 alleles/locus (range 2–17). The average heterozygosity value for each SSR locus ranged from 0 to 0.60, and the highest one was 0.96 (Fl0516 in 4013). The mean polymorphism index content (PIC) was 0.66 (range 0.12–0.89). Unweighted pair group method with arithmetic means (UPGMA) cluster analysis of Nei's genetic distance grouped silkworm strains based on their origin. Seven major ecotypic silkworm groups were analyzed. Principal components analysis (PCA) for SSR data support their UPGMA clustering. The results indicated that SSR markers are an efficient tool for fingerprinting cultivars and conducting genetic-diversity studies in the silkworm.Key words: silkworm, Bombyx mori L., microsatellites, simple sequence repeat (SSR), genetic diversity.

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Genetic relationships of boxwood (Buxus L.) accessions based on genic simple sequence repeat markers

Genetic Resources and Crop Evolution ◽

10.1007/s10722-016-0436-6 ◽

2016 ◽

Vol 64 (6) ◽

pp. 1281-1293 ◽

Cited By ~ 10

Author(s):

Chandra S. Thammina ◽

Richard T. Olsen ◽

Matthew Kramer ◽

Margaret R. Pooler

Keyword(s):

Simple Sequence Repeat ◽

Genetic Relationships ◽

Sequence Repeat ◽

Simple Sequence Repeat Markers ◽

Simple Sequence

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Comparative Analysis of Genetic Similarity between Perennial Ryegrass Genotypes Investigated With AFLPs, ISSRs, RAPDs and SSRs

Czech Journal of Genetics and Plant Breeding ◽

10.17221/3647-cjgpb ◽

2011 ◽

Vol 42 (No. 3) ◽

pp. 87-94 ◽

Cited By ~ 14

Author(s):

U.K. Posselt ◽

P. Barre ◽

G. Brazauskas ◽

L.B. Turner

Keyword(s):

Perennial Ryegrass ◽

Simple Sequence Repeat ◽

Fragment Length Polymorphism ◽

Genetic Relationships ◽

Random Amplified Polymorphic Dna ◽

Correlation Coefficients ◽

Inter Simple Sequence Repeat ◽

Grass Species ◽

Sequence Repeat ◽

Simple Sequence

Perennial ryegrass (Lolium perenne L.) is the most important grass species used in temperate grassland agriculture. Our objective was to obtain an overview of the genetic relationships between 20 individual genotypes of perennial ryegrass of diverse origins, using amplified fragment length polymorphism (AFLP), inter-simple sequence repeat (ISSR), random amplified polymorphic DNA (RAPD) and two sets of simple sequence repeat (SSR) markers. All 20 individuals were uniquely fingerprinted by all four marker systems and comparisons were made on the basis of 85 markers each. Mean genetic similarities were estimated at 0.31, 0.43, 0.23 and 0.15 for AFLPs, ISSRs, RAPDs and SSRs, respectively. Cophenetic values resulted in good (AFLP and SSR-B = 0.88) to moderately good fits (ISSR = 0.76, RAPD = 0.70, and SSR-A = 0.79). Comparing the four marker systems to each other, AFLP and SSR-A were correlated best (r = 0.57). All other comparisons revealed rather low correlation coefficients in the Mantel Z test. With twice as many markers cophenetic values increased to a very good fit for AFLPs (0.90) and SSRs (0.92).      

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