scholarly journals Development and application of microsatellites in plant breeding

2011 ◽  
Vol 11 (spe) ◽  
pp. 66-72 ◽  
Author(s):  
Maria Celeste Gonçalves-Vidigal ◽  
Luciana Benchimol Rubiano

Molecular markers are powerful tools for analyzing genome diversity within a species, and to evaluate genetic relationships between individuals and populations. Among them, microsatellites (SSRs) are one of the most important polymorphic markers that can be used effectively to distinguish germplasm accessions. These markers present high informative content due to their codominant inheritance, multiallelism, mendelian pattern and good genome coverage. The enrichment methodology for microsatellite development has a superior efficiency in plants, especially when performed using biotin-labeled microsatellite oligoprobes and streptavidin-coated magnetic beads. The development of EST-SSR markers has become a fast and relatively inexpensive way but it is limited to species for which this type of database exists. Given the high polymorphism level of microsatellites when compared to other markers, SSRs have been used to study population structure, for genetic diversity analysis, genetic mapping and marker assisted selection.

Author(s):  
Mohamed Abd. S. El zayat ◽  
Mahmoud El Sayd Ali ◽  
Mohamed Hamdy Amar

Abstract Background The Capparaceae family is commonly recognized as a caper, while Cleomaceae represents one of small flowering family within the order Brassicales. Earlier, Cleomaceae was included in the family Capparaceae; then, it was moved to a distinct family after DNA evidence. Variation in habits and a bewildering array of floral and fruit forms contributed to making Capparaceae a “trash-basket” family in which many unrelated plants were placed. Indeed, family Capparaceae and Cleomaceae are in clear need of more detailed systematic revision. Results Here, in the present study, the morphological characteristics and the ecological distribution as well as the genetic diversity analysis among the twelve species of both Capparaceae and Cleomaceae have been determined. The genetic analysis has been checked using 15 ISSR, 30 SRAP, and 18 ISTR to assess the systematic knots between the two families. In order to detect the molecular phylogeny, a comparative analysis of the three markers was performed based on the exposure of discriminating capacity, efficiency, and phylogenetic heatmap. Our results indicated that there is a morphological and ecological variation between the two families. Moreover, the molecular analysis confirmed that ISTR followed by SRAP markers has superior discriminating capacity for describing the genetic diversity and is able to simultaneously distinguish many polymorphic markers per reaction. Indeed, both the PCA and HCA data have drawn a successful annotation relationship in Capparaceae and Cleome species to evaluate whether the specific group sort individual or overlap groups. Conclusion The outcomes of the morphological and ecological characterization along with the genetic diversity indicated an insight solution thorny interspecies in Cleome and Gynandropsis genera as a distinct family (Cleomaceae) and the other genera (Capparis, Cadaba, Boscia, and Maerua) as Capparaceae. Finally, we recommended further studies to elucidate the systematic position of Dipterygium glaucum.


2020 ◽  
Author(s):  
Yusen Shen ◽  
Jiansheng Wang ◽  
Huifang Yu ◽  
Xiaoguang Sheng ◽  
Zhenqing Zhao ◽  
...  

Abstract Background: Broccoli (Brassica oleracea var. italica) is a vegetable widely cultivated in China. Many new-type broccoli cultivars were bred and developed by Chinese breeders during the recent three decades. However, the broccoli cultivar nomenclature and detailed information of genetic relationships among broccoli germplasms are unclear. Results: The present study identified millions of SNPs by next-generation sequencing of 23 representative broccoli lines. Through several steps of selection, 100 SNPs were successfully converted into KASP markers, and used to evaluate the genetic diversity, genetic relationship, and population structure of 392 broccoli accessions, which represent the mainly broccoli breeding materials in China. The initial, introduced and improved accessions were well clustered, though some accessions were overlapped between groups, probably reflecting the fact that breeding activities led to genetic similarities. To make the KASP genotyping more efficient and cost-effective, 25 of the 100 KASPs were selected for fingerprinting of all accessions, and the 2D barcode contained fingerprinting information were generated for elite varieties. Conclusion: The KASP markers developed in this study provided an efficient way for germplasm characterization, DNA fingerprinting, seed purity identification, and marker-assisted selection of broccoli in China.


2021 ◽  
pp. 36-48
Author(s):  
Farhana Afrin Vabna ◽  
Mohammad Zahidul Islam ◽  
Md. Ferdous Rezwan Khan Prince ◽  
Md. Ekramul Hoque

Aims: The aim of the study was to determine the genetic diversity of twenty four Boro rice landraces using rice genome specific twelve well known SSR markers. Study Design: Genomic DNA extraction, PCR amplification, Polyacrylamide gel electrophoresis (PAGE) and data analysis-these steps were followed to perform the research work. Data was analysed with the help of following software; POWERMAKER version 3.25, AlphaEaseFC (Alpha Innotech Corporation) version 4.0. UPGMA dendrogram was constructed using MEGA 5.1 software. Place and Duration of Study: The study was conducted at the Genetic Resources and Seed Division (GRSD), Bangladesh Rice Research Institute (BRRI), Joydebpur, Gazipur, Bangladesh during the period of November 2017 to March 2018. Methodology: Simple Sequence Repeat (SSR) markers were used to assay 24 landraces of Boro rice collected from the Gene Bank of Bangladesh Rice Research Institute (BRRI). Results: A total fifty four (54) alleles were detected, out of which forty five (45) polymorphic alleles were identified. The Polymorphic Information Content (PIC) of SSR markers ranged from 0.08 (RM447) to 0.84 (RM206) with an average value of PIC = 0.49. Gene diversity ranges from 0.08 (RM447) to 0.86 (RM206) with an average value of 0.52. The RM206 marker can be considered as the best marker among the studied markers for 24 rice landraces. Dendrogram based on Nei’s genetic distance using Unweighted Pair Group Method of Arithmetic Mean (UPGMA) indicated the segregation of 24 genotypes into three main clusters. Conclusion: The result revealed that SSR markers are very effective tools in the study of genetic diversity and genetic relationships and this result can be conveniently used for further molecular diversity analysis of rice genotypes to identify diverse parent for the development of high yielding variety in rice.


1995 ◽  
Vol 66 (1) ◽  
pp. 71-83 ◽  
Author(s):  
J. Ruane ◽  
J. J. Colleau

SummaryA Monte Carlo simulation study to evaluate the benefits of marker assisted selection (MAS) in small populations with one marked bi-allelic quantitative trait locus (QTL) is described. In the base generation, linkage phase equilibrium between the markers, QTL and polygenes was assumed and frequencies of 0·5 for the two QTL alleles were used. Six discrete generations of selection for a single character measured on both sexes followed. An additive genetic model was used with the QTL positioned midway between two highly polymorphic markers. Schemes were simulated with a distance of 10 cM between the QTL and either of the two markers and with the QTL explaining 1/8 of the total genetic variance in the base generation. Values of 0·5, 0·25 or 0·1 were assumed for the heritability. Eight males and 16, 32 or 64 females were selected each generation with each dam producing four sons and four daughters as candidates for the next generation. Animals were evaluated with a conventional BLUP animal model or with a model using marker information. MAS resulted in substantially higher QTL responses (4–54%), especially with low heritabilities, than conventional BLUP but lower polygenic responses (up to 4%) so that the overall effect on the total genetic response, although in the majority of cases favourable, was relatively small. With QTLs of larger size (explaining 25% of the genetic variance) comparable results were found. When the distance between the QTL and the markers was reduced to 2 cM, genetic responses were increased very slightly with a heritability of 0·5 whereas with a heritability of 0·1 responses were increased by up to 10%, compared with conventional BLUP. Results emphasize that MAS should be most useful for lowly heritable traits and that once QTLs for such traits have been identified the search for closely linked polymorphic markers should be intensified.


2011 ◽  
Vol 63 (3) ◽  
pp. 667-679 ◽  
Author(s):  
Kumar Mishra ◽  
Sandhyarani Nishani ◽  
J Jayarama

The identification and genetic relationships of 23 coffee species and one coffee-related species Canthium diccocum were studied using ISSR and SRAP markers. The average polymorphism information content of SRAP primers (0.81) was lower than ISSR primers (0.86), whereas the average resolving power of the SRAP primers (9.74) is higher than the ISSR primers (8.64). The genetic similarity among the species ranged from 0.30 to 0.89 using ISSR and 0.11 to 0.90 using SRAP marker systems. Based on marker analysis, all twenty three coffee species were clustered into two major groups. Both the markers amplified species-specific fragments and are useful in genetic diversity analysis of coffee.


Genetika ◽  
2015 ◽  
Vol 47 (3) ◽  
pp. 983-992
Author(s):  
Zelmíra Balázová ◽  
Andrej Trebichalský ◽  
Zdenka Gálová ◽  
Radomíra Hornyák-Gregáňová

Present study aims to testify usefulness of particular wheat SSR markers for the detection of genetic diversity degree in the set of 59 triticale cultivars and new lines coming from different European countries and USA. For this purpose, a set of fifteen SSR markers were used. One SSR marker (Xwmc429) gave a uniform spectrum. The set of fourteen polymorphic markers provided 94 alleles with an average frequency of 6.71 alleles per locus. The number of alleles ranged between 2 (Xbarc 195) and 10 (Xbarc 137). Resulting from the number and frequency of alleles, diversity index (DI), polymorphic information content (PIC) and probabilities of identity (PI) were calculated. An average value of PIC for 14 markers was 0.640, the highest value was calculated for wheat SSR marker Xgwm 46 (0.809). Based on UPGMA algorithm, a dendrogram was constructed. It was able to separate 57 of 59 cultivars (96,6 %) from each other. American new-line NE-422T significantly separated from all cultivars and new lines. Only two french cultivars Bienvenu and Wilfried had not been separated from each other. A tested set of SSR markers allowed to better understand genetic relationships among European cultivars and American new lines. In general, a dendrogram along with results of calculated genetic indicators such as PIC, PI and DI point out at SSRs markers as high informative and usefull tool in genetic diversity research between close-related species.


Genome ◽  
1994 ◽  
Vol 37 (3) ◽  
pp. 506-508 ◽  
Author(s):  
S. A. Aitken ◽  
N. A. Tinker ◽  
D. E. Mather ◽  
M. G. Fortin

Molecular markers linked to loci of interest can be used for fine mapping a particular area of a genome or for marker-assisted selection. We present an approach for screening individual plants with polymorphic markers that facilitates phenotyping in large populations. Polymorphic DNA fragments, amplified by PCR, are labelled with digoxigenin and used as probes on slot blots of amplified DNA from the individual plants to be tested. DNA is obtained by a simple two-tube purification method. The colorimetric detection of alleles on the blots is more reliable, and more amenable to automation, than conventional staining of electrophoresis gels.Key words: molecular markers, RAPD, genetic mapping, breeding.


Sign in / Sign up

Export Citation Format

Share Document