• Journal of Plant Biotechnology
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• v.5 no.4
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• pp.193-195
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• 2003

A major goal of agricultural biotechnology is the discovery of genes or genetic loci which are associated with characteristics beneficial to crop production. This knowledge of genetic loci may then be applied to improve crop breeding. Agriculturally important genes may also benefit crop production through transgenic technologies. Recent years have seen an application of high throughput technologies to agricultural biotechnology leading to the production of large amounts of genomic data. The challenge today is the effective structuring of this data to permit researchers to search, filter and importantly, make robust associations within a wide variety of datasets. At the Plant Biotechnology Centre, Primary Industries Research Victoria in Melbourne, Australia, we have developed a series of tools and computational pipelines to assist in the processing and structuring of genomic data to aid its application to agricultural biotechnology resear-ch. These tools include a sequence database, ASTRA, for the processing and annotation of expressed sequence tag data. Tools have also been developed for the discovery of simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) molecular markers from large sequence datasets. Application of these tools to Brassica research has assisted in the production of genetic and comparative physical maps as well as candidate gene discovery for a range of agronomically important traits.

• Journal of Ginseng Research
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• v.35 no.4
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• pp.399-412
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• 2011

Little is known about the genetics or genomics of Panax ginseng. In this study, we developed 70 expressed sequence tagderived polymorphic simple sequence repeat markers by trials of 140 primer pairs. All of the 70 markers showed reproducible polymorphism among four Panax species and 19 of them were polymorphic in six P. ginseng cultivars. These markers segregated 1:2:1 manner of Mendelian inheritance in an $F_2$ population of a cross between two P. ginseng cultivars, 'Yunpoong' and 'Chunpoong', indicating that these are reproducible and inheritable mappable markers. A phylogenetic analysis using the genotype data showed three distinctive groups: a P. ginseng-P. japonicus clade, P. notoginseng and P. quinquefolius, with similarity coefficients of 0.70. P. japonicus was intermingled with P. ginseng cultivars, indicating that both species have similar genetic backgrounds. P. ginseng cultivars were subdivided into three minor groups: an independent cultivar 'Chunpoong', a subgroup with three accessions including two cultivars, 'Gumpoong' and 'Yunpoong' and one landrace 'Hwangsook' and another subgroup with two accessions including one cultivar, 'Gopoong' and one landrace 'Jakyung'. Each primer pair produced 1 to 4 bands, indicating that the ginseng genome has a highly replicated paleopolyploid genome structure.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.401-408
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• 2015

Horticultural traits and genetic relationship were evaluated for 83 melon (Cucumis melo L.) cultivars. Survey of a total of 36 characteristics for seedling, leaf, stem, flower, fruit, and seed and subsequent multiple analysis of variance (MANOVA) were conducted. Principal component analysis (PCA) showed that 8 principle components including fruit weight, fruit length, fruit diameter, cotyledon length, seed diameter, and seed length accounted for 76.3% of the total variance. Cluster analysis of the 83 melon cultivars using average linkage method resulted in 5 clusters at coefficient of 0.7. Cluster I consisted of cultivars with high values for fruit-related traits, Cluster II for soluble solid content, and Cluster V for high ripening rate. Genotyping of the 83 cultivars was conducted using 15 expressed-sequence tagged-simple sequence repeat (EST-SSR) from the Cucurbit Genomics Initiative (ICuGI) database. Analysis of genetic relatedness by UPGMA resulted in 6 clusters. Mantel test indicated that correlation between morphological and genetic distance was very low (r = -0.11).

• Korean Journal of Plant Taxonomy
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• v.50 no.1
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• pp.22-26
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• 2020

Chrysosplenium aureobracteatum Y. I. Kim & Y. D. Kim (Saxifragaceae) is a recently described endemic species growing in the central part of the Korean peninsula. It requires constant monitoring for conservation due to its limited distributions. There is also a need for molecular markers for proper assessments of the genetic differentiation of C. aureobracteatum from species morphologically similar to it. In this study, we developed microsatellite markers that can be used to evaluate the genetic diversity of this species, representing fundamental data with which to conserve the natural populations of the species. A total of 17 expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed by the Illumina pair-end sequencing of the transcriptomes of C. aureobracteatum. These markers were successfully applied to populations of C. aureobracteatum and to its most closely related species, C. barbatum, revealing high polymorphism in both species. The EST-SSR markers developed in this study were proven to be useful not only to monitor the population genetic structure of C. aureobracteatum for conservation purposes but also to study the genetic delimitation of the species from species closely related to it.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.443-451
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• 2021

Finger millet (Eleusine coracana) is widely cultivated in tropical regions worldwide owing to its high nutritional value. Finger millet is more tolerant against biotic and abiotic stresses such as pests, drought, and salt than other millet crops; therefore, it was proposed as a candidate crop to adapt to climate change in Korea. In 2019, we used expressed sequence tag simple sequence repeat (EST-SSR) markers to evaluate the genetic diversity and structure of 102 finger millet accessions from two geographical regions (Africa and South Asia) to identify appropriate accessions and enhance crop diversity in Korea. In total, 40 primers produced 116 alleles, ranging in size from 135 to 457 bp, with a mean polymorphism information content (PIC) of 0.18225. Polymorphism was detected among the 40 primers, and 13 primers were found to have PIC values > 0.3. Principal coordinate and phylogenetic analyses, based on the combined data of both markers, grouped the finger millet accessions according to their respective collection areas.Therefore, the 102 accessions were classified into two groups, one from Asia and the other from Africa. We have conducted an in-depth study on the finger millet landrace pedigree. By sorting out and using the molecular characteristics of each pedigree, it will be useful for the management and accession identification of the plant resource. The novel SSR markers developed in this study will aid in future genetic analyses of E. coracana.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.772-781
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• 2013

The objective of this study was to develop simple sequence repeat (SSR) markers from expressed sequence tags (EST) of lettuce (Lactuca sativa) and identify 9 germplasms from 3 wild species of lettuce and 61 commercial cultivars using the developed EST-SSR markers. A total of 81,330 lettuce ESTs from NCBI databases were used to search for SSR and 4,229 SSR loci were identified. The highest proportion (59.12%, 2500) was represented by trinucleotide, followed by dinucleotide (29.70%, 1256) and hexanucleotide (6.62%, 280) among SSR repeat motifs. Totally 474 EST-SSR primers were developed from EST and a random set of 267 primers was used to assess the genetic diversity among 9 germplasms and 61 cultivars. Out of 267 primers, 47 EST-SSR markers showed polymorphism between 7 cultivars. Twenty-six EST-SSR markers among 47 EST-SSR markers showed high polymorphism, reproducibility, and band clearance. The relationship between 26 markers genotypes and 70 accessions was analyzed. Totally 127 polymorphic amplified fragments were obtained by 26 EST-SSR markers and two to nine SSR alleles were detected for each locus with an average of 4.88 alleles per locus. Average polymorphism information content was 0.542, ranging from 0.269 to 0.768. Genetic distance of clusters ranged from 0.05 to 0.94 between 70 accessions and dendrogram at a similarity of 0.34 gave 7 main clusters. Analysis of genetic diversity revealed by these 26 EST-SSR markers showed that the 9 germplasms and 61 commercial cultivars were discriminated by marker genotypes. These newly developed EST-SSR markers will be useful for cultivar identification and distinctness, uniformity and stability test of lettuce.

• Korean Journal of Medicinal Crop Science
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• v.20 no.4
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• pp.277-285
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• 2012

In this study, Expressed Sequence Tag-Simple Sequence Repeat (EST-SSR) analyses were used to clarify the genetic polymorphisms among Korean ginseng cultivars and breeding lines and to classify them into distinct genetic groups. Polymorphic and reproducible bands were produced by 14 primers out of total 30 primers used in this study. Fourteen EST-SSR loci generated a total of 123 bands. Amplified PCR products showed the highly reproducible banding patterns at 110~920 bp. The number of amplified bands for each EST-SSR primers ranged from 2 to 19 with a mean of 8.8 bands. P26 and P35 primers showed 13 and 12 banding patterns, respectively. The number of alleles for each EST-SSR locus ranged from 1.67 to 2.00 with a mean of 1.878 alleles. P34 and P60 primers showed the highest and the lowest genetic polymorphism, respectively. Cluster analysis based on genetic similarity estimated by EST-SSR markers classified Korean cultivars and breeding lines into 4 groups. Group included Gopoong and Chunpoong and 9 breeding lines (55%), group included 2 breeding lines (10%), group included 3 breeding lines (15%), group included Gumpoong and 3 breeding lines (20%). Consequently, the EST-SSR marker developed in this study may prove useful for the evaluation of genetic diversity and differentiation of Korean ginseng cultivars and breeding lines.