• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.1
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• pp.19-27
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• 2002

To investigate the dominant species and factors related with plant coverage by road structures and forest environment factors, forest roads elapsed from one year to twelve year after construction had been selected in six county(Gochang-gun, Muju-gun, Imsil-gun, Jangsu-gun, Jeongup-shi and Jinan-gun), and 20m segments were continuously set up in each road. The results obtained from this study are summarized as follows: The species diversity of Gochang, Muju, Imsil, Jangsu, Jeongup and Jinan were 1.304, 1.267, 1.308, 1.193, 1.289 and 1.018, respectively. In process of years, plant coverage was increased gradually and average of plant coverage was 15.3% in forest roads which elapsed three year, and was 86.5% in forest roads which elapsed nine year after construction. The dominant species in the cutting slope of surveyed area were covered with Arundinella hirta, Pinus rigida, Miscanthus sinensis var. purpurascens, Artemisia princeps var. orientalis, Pinus densiflora, Oplismenus undulatifolius, Rubus coreanus, Lysimachia clethroides, Lespedeza bicolor, and Alnus hirsuta of the 152 species. The high correlated factors between plant coverage and variables in cutting slopes appeared elapsed year, soil hardness, mean annual precipitation, vertical grade, inslope and arid humidity in surveyed area.

• Proceedings of the Korean Society of Crop Science Conference
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• 2007.04a
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• pp.76.2-76.2
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• 2007

• The Plant Pathology Journal
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• v.22 no.1
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• pp.28-35
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• 2006

Virulence and genetic diversity were studied using 21 isolates of Sclerospora graminicola, the pearl millet downy mildew pathogen collected from major pearl millet growing areas of India. Variability for virulence was determined by inoculating a set of 10 differential hosts with the S. graminicola isolates in a greenhouse. The isolates varied for latent period (6.4 to 11 days), disease incidence (0 to $98\%$), virulence index (0 to 18.7) and oospore-production potential (1 to 4). Among the 21 isolates, Sg 139 (Rajasthan) was the most virulent and Sg 110 (Tamil Nadu) the least virulent. Based on virulence index (disease incidence$\time$slatent $period^{-1}$), the 21 isolates were classified into eight virulence groups. Genetic diversity among isolates was studied using AFLP markers. Based on similarity index of banding pattern, the 21 isolates were clustered into eight genotypic groups. The AFLP groupings, however, did not match with that of the virulence groupings, and these two were found independent. The isolate Sg 139 that remained distinct in both pathogenic and genetic groupings indicated its highly virulent nature. Implications of these results in downy mildew resistance breeding are discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.256-262
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• 1999

To evaluate the genetic diversity and structure of the South Korean soybean population, 233 landraces collected in various regions of the country were surveyed for 15 allozyme loci and one protein locus. The South Korean population was fixed or nearly fixed at seven of the 16 loci tested. The number of alleles per locus was 2.06 and Nei’s gene diversity was 0.194. These values were lower than the values for the same 16 loci previously reported for the Japanese and Chinese populations. The differences among eight regional groups were not so marked, with only 7.2% of the total variation arising from regional differentiation. Three southern regional groups (Chollabuk-do, Chollanam-do and Kyong-sangnam-do) exhibited a relatively high variability because of frequent occurrence of alleles characteristic of the Japanese population. A marked difference was found in allelic frequencies at the Dial locus between large-seeded landraces and small-seeded ones, suggesting that the latter, which are used mainly for bean sprouts, had been established independently of the former, which are used mostly for soy sauce and cooking with rice. Not only the region but also the usage as food materials should therefore be taken into consideration in designing an efficient collection and preservation method for the Korean soybean landraces.

• Korean Journal of Oriental Medicine
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• v.14 no.3
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• pp.49-56
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• 2008

Glehnia littoralis Fr. Schmidt et Miquel is an important medicinal plants in East Asian countries. This plant species naturally distributed in Korea, Japan, China, and Taiwan, but it is a rare plants living in the coastal dune in Korea. To investigate the genetic variation, genetic diversity and genetic evolutionary relationships of 14 different geographical G. littoralis, ITS sequence and random amplified polymorphic DNA (RAPD) were analyzed. On the basis of ITS sequences, it was clearly showed that the ITS1 and ITS2 sequences among 14 populations are identical regardless of geographical origin excepting 2 bp in pair-wise comparison of ITS1. Furthermore, RAPD results also showed that 14 different geographical G. littoralis produce various polymorphic patterns without critical relationship among neighboring regions. These combined results suggest that the geographical variation and genetic evolution of G. littoralis is stable and provide important information on genetic diversity, and conservation of this rare plant species in situ and ex situ.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.13-24
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• 2012

The genetic diversity of plant growth-promoting rhizobacterial (PGPR) fluorescent pseudomonads associated with the sugarcane (Saccharum officinarum L.) rhizosphere was analyzed. Selected isolates were screened for plant growthpromoting properties including production of indole acetic acid, phosphate solubilization, denitrification ability, and production of antifungal metabolites. Furthermore, 16S rDNA sequence analysis was performed to identify and differentiate these isolates. Based on 16S rDNA sequence similarity, the isolates were designated as Pseudomonas plecoglossicida, P. fluorescens, P. libaniensis, and P. aeruginosa. Differentiation of isolates belonging to the same group was achieved through different genomic DNA fingerprinting techniques, including randomly amplified polymorphic DNA (RAPD), amplified ribosomal DNA restriction analysis (ARDRA), repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC), and bacterial repetitive BOX elements (BOX) analyses. The genetic diversity observed among the isolates and rep-PCR-generated fingerprinting patterns revealed that PGPR fluorescent pseudomonads are associated with the rhizosphere of sugarcane and that P. plecoglossicida is a dominant species. The knowledge obtained herein regarding the genetic and functional diversity of fluorescent pseudomonads associated with the sugarcane rhizosphere is useful for understanding their ecological role and potential utilization in sustainable agriculture.

• Journal of Plant Biology
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• v.38 no.4
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• pp.329-336
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• 1995

Raphanus sativus L. var. hortensis f. raphanistroides (wild radish: Brassicaceae), a herbaceous perennial, occurs only on beaches in East Asia. Genetic diversity and population structure of seven Korean populations were investigated using starch gel electrophoresis. Although the Korean populatins are small, isolated with patchy distribution, the population maintain a moderate level of genetic diversity; the mean percentage fo polymorphic loci was 51.4%, mean number of alleles per locus was 1.84, and mean expected heterozygosity was 0.116. A combination of animal-outcrossing breeding system, wide geographical distribution, restricted ecological distribution, and a propensity for high fecundity may in part be explanatory factors contributing the moderate level of genetic diversity within populations. An overall excess of homozygotes relative to Hardy-Weinberg expetations (mean FISa=0.116) indicates that consanguineous mating occur within wild radish populations, leading to a family structure within a circumscribed area. Although population of wild radish experience a limited gene flow, only 5% of the total genetic variation found in Korean wild radish populations examined is due to differences among populations (mean GST=0.052). This value is considerably lower than the mean values of species with similar life history and ecological characteristics. However, significant differences were found in allele frequencies between populations for all polymorphic loci (P<0.01). It is supposed that directional selection toward genetic uniformity (similar gene frequencies) in a relatively homogenous habitat is thought to be operated among Korean wild radish populations.

• Korean Journal of Plant Resources
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• v.25 no.3
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• pp.329-338
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• 2012

Genus Taraxacum has been widely used as a folkloric medicine for treatment of diverse diseases. The genetic diversity and relationship among 32 accessions belonging to five Taraxacum species (T. mongolicum T. coreanum, T. coreanum var. flavescens, T. officinale and T. laevigatum) which collected from field, mountain, island and seaside of Korea were evaluated using ISSR markers. A total of 142 ISSR loci detected in the overall species were all polymorphic loci (100%) and interspecies polymorphisms obtained from Korean native and naturalized species were 98.2% and 94.5%, respectively. The genetic similarity matrix (GSM) among 32 accessions ranged from 0.025 to 0.860 with an average of 0.303. According to the clustering analysis, the Korean native species and naturalized species were divided two major clusters. In addition, the different species were divided into independent groups except for the T. coreanum and T. coreanum var. flavescens, and all the 32 accessions could be classified into 7 categories. The study findings indicate that Taraxacum accessions have a high genetic diversity and the dandelion accessions as breeding materials can be effectively utilized for the improvement of Taraxacum breeding.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.530-539
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• 2007

Genetic variation and structure of 9 subpopulations of Symplocarpus renifolius Schott ex Tzvelev on Mt. Cheonma, in Korea, were determined via starch-gel electrophoresis. The genetic diversity at 10 loci for 8 isozymes ($P_{99}=66%,\;A=2.26,\;H_o=0.212,\;H_e=0.230$) was found to be considerably higher than that seen in other long-lived perennial plants. On the whole, the genotype frequencies were in accordance with Hardy-Weinberg expectations. Approximately 5%($\theta=0.049$) of the total variability was among subpopulations. The high levels of observed genetic diversity in S. renifolius were attributed to a universal outcrossing system and other specific factors like differences in age classes and widely scattered individuals around the main distribution. Heterozygosity was highest at a mid-range of elevation($450m{\sim}600m$). The lowest heterozygosity at lower elevation was attributed to the possible origin of seeds transported by water from upstream regions during the monsoon season. Spatial structure in a subpopulation evidenced a strong autocorrelation between closer individuals within $3{\sim}4m$ of distance. This was assumed to be attributable to the restricted seed dispersal characteristics of S. renifolius. In accordance with the findings generated in this study, some implications regarding the conservation of S. renifolius at the Mt. Cheonma were also presented.

• Korean Journal of Plant Resources
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• v.21 no.3
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• pp.216-221
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• 2008

The Purpose of this study was to offer the raw data for drawing up the conservation plan by analysing natural vegetation in Midongsan, Chungcheongbuk-do, Korea. The period of survey was from July to October, 2004 and the size of plot was 100$m^2$. In the results of analyzing the physical environments, the range of altitude was 303${\sim}$550m and soil pH was 5.4${\sim}$6.8. The angle of slope was 3${\sim}$57% and topographical factor was composed of ridgeline. In the results of analyzing a importance percentage, the dominant species in tree layer, Pinus rigida, P. densiflora, Quercus mongolica, Q. variabilis and Q. acutissima, P. rigida, Q. mongolica, Q. acutissima, Platycarya strobilacea and Q. variabilis in subtree layer, Rhododendron mucronulatum, Symplocos chinensis for pilosa, Lindera obtusiloba, L. erythrocarpa, Rhus trichocarpa and Weigela subsessilis in shrub layer. In the results of species diversity index, species diversity (H') was from 1.2401 to 2.5540, maximum species diversity (H'max), from 1.9459 to 2.8904, evenness (J'), from 0.5644 to 0.8836, dominance (D), from 0.1164 to 0.4356.