• Journal of Korean Society of Forest Science
• /
• v.95 no.4
• /
• pp.435-442
• /
• 2006

A total of 167 peculiar haplotypes confirmed from 28 cpSR variants that were observed in 19 populations of Japanese red pine in Korea through cpSSR marker analysis. Thirteen individuals that showed identical haplotype dispersed evenly in 10 populations, and the average number of effective haplotype within population was 13.37. Estimate of genetic diversity (He) was 0.987 on the basis of cpSSR haplotype variants that was equivalent to or higher than the estimates reported in other studies on some forest tree species. Estimation of genetic diversity (S.I.) on the basis of cpSSR variants composing each haplotype revealed the highest estimate of 1.109 for the population of Gangwon-Yeongwol and the lowest estimate of 0.411 for the population of Gyeongbuk Mungyeong with the average of 0.887. Most of observed cpSSR variants appeared to exist commonly in 19 populations (97.62%), and genetic differentiation of cpSSR variants among populations was turned out to be weak (${\Phi}_{ST}=0.024$). Relatively fast rate of mutation of cpSSR marker might be a major cause for such weak population differentiation. There was no identical haplotype shared between 39 population pairs of 173 pair-wise population pairs. Estimation of genetic distance among 19 populations on the basis of population pairs was also impossible, that might be resulted from restricted migration among 19 populations. Considering the observed distribution patterns of cpSSR variants in addition to the previous studies on I-SSR variants, informations on the present geographic location and genetic status of populations should be considered together for effective sustainable management of the genetic resources of Japanese red pine in Korea.

• Journal of Korean Society of Forest Science
• /
• v.87 no.3
• /
• pp.422-428
• /
• 1998

Polymerase chain reaction(PCR)-based inter-simple sequence repeats(I-SSR) markers were analyzed in 48 megagametophytes of a single tree of Abies koreana $W_{ILS}$. Nineteen of the 35 primers, screened with 6 megagametophyte DNA and produced the clearest amplification products in the preliminary experiment, were used for PCR with 48 megagametophyte DNAs sampled from a single tree. On the basis of the chi-square test, a total of 51 amplicons, amplified by the 19 primers, were revealed to be segregated according to the Mendelian ratio(i.e., 1 : 1 segregation ratio) in the 48 megagametophytes at 5% significance level. Based on the linkage analysis, the observed 51 Mendelian loci turned out to be unlinked each other, which suggested that they are evenly distributed in the genome. However, majority of RAPD markers are known to belong to the independent linkage blocks, which frequently results in the amplification of RAPD markers from the restricted regions of the genome. Owing to the nature of even distribution of the 51 loci observed in this study, the I-SSR markers could give better resolution of estimating genetic diversity from the whole genome than RAPD markers. And I-SSR markers are also more suitable than RAPD markers for reconstructing phylogenetic relationship by a cladistic method which requires to fulfil the assumption of independent evolution of the different characters.

• Journal of Korean Society of Forest Science
• /
• v.102 no.1
• /
• pp.59-65
• /
• 2013

The jujube is an important fruit tree species in Korea. Traditionally, classifications of jujube cultivars have been based on morphological characters; however, morphological identification can be problematic because morphological traits are affected by environmental conditions. Therefore, DNA markers are now being used for the rapid and accurate identification of plant species. Inter-simple sequence repeat (I-SSR) is one of the best DNA-based molecular marker techniques, which is useful for studying genetic relations and for the identification of closely related cultivars. In this study, 5 Korean jujube trees and 1 jujube tree imported from China were analyzed for 16 I-SSR primers. Amplification of the genomic DNA of jujube cultivars by using I-SSR analysis generated 100 bands, with an average of 6.25 bands per primer, of which 45 bands (45%) were polymorphic. The number of amplified fragments with I-SSR primers ranged from 2 to 13. The percentage of polymorphism ranged from 10% to 100%. I-SSR finger printing profiles showed that 'Boeun jujube' and 'Daeri jujube' had characteristic DNA patterns, indicating unequivocal cultivar identification at molecular level. According to the results of clustering analysis, the genetic similarity coefficient ranged from 0.68 to 0.92. 'Boeun jujube' and 'Daeri jujube' were divided into independent groups, and 'Bokjo jujube', 'Geumseong jujube', 'Wolchul jujube', and 'Mudeung jujube' were placed in the same group. Therefore, I-SSR markers are suitable for the discrimination of 'Boeun jujube' and 'Daeri jujube' cultivars.

• Journal of Korean Society of Forest Science
• /
• v.90 no.2
• /
• pp.169-175
• /
• 2001

Genomic DNAs were extracted from the leaves of 182 ginkgo trees (Ginkgo biloba L.) planted in 6 regions and subjected to the analysis of both I-SSR and RAPD markers. A total of 227 amplicon variants were generated by PCR using 15 I-SSR primers and 67 amplicons by PCR with 5 RAPD primers. Levels of genetic diversity within 6 populations were turned out to be similar (Shannon's Index, I-SSR : 0.35~0.40; mean of 0.38, RAPD : 0.31~0.38; mean of 0.35, combined : 0.35~0.40; mean of 0.37). Ranks of the level of genetic diversity estimated from I-SSR, RAPD, and combined data were not coincided each other. Majority of genetic diversity was allocated among individuals within populations (I-SSR : 94.31%, RAPD : 93.62%, combined : 93.57%), which resulted in pretty low level of population differentiation. Genetic differentiation between male and female groups was turned out to be quite low (I-SSR : 0.03, RAPD : 0.091, combined : 0.043), which slightly fluctuated when analysis was restricted to the data obtained from 3 regions where both male and female trees were sampled (I-SSR : 0.038, RAPD : 0.084, combined : 0.047). Genetic relationships among the populations, reconstructed by UPGMA, were not coincided with geographic affinity, which might be resulted from sharing of seed sources in some regions. Whereas independent cluster analyses with I-SSR data and RAPD data, respectively, reclassified by sexes revealed two sexual groups in which all the male and the female populations were clustered together, cluster analysis with combined data did not show clear sexual grouping.

• Horticultural Science & Technology
• /
• v.32 no.1
• /
• pp.84-90
• /
• 2014

Berchemia racemosa var. magna is only found in Anmyeon Island of South Korea. Genetic diversity and the spatial genetic structure of B. racemosa var. magna in Anmyeon Island were studied by I-SSR marker system. Fifty I-SSR amplicons were produced from 8 selected primers. We used 13 polymorphic markers to analyze the genetic structure. Distribution of 39 individuals in the study plot($90m{\times}70m$) showed aggregate pattern (aggregation index = 0.706). Total 21 genets were observed from 39 individuals through I-SSR genotyping. Proportion of distinguishable genotype (G/N), genotype diversity (D) and genotype evenness (E) were 53.8%, 0.966 and 0.946, respectively. In spite of the small number and the narrow distribution, Shannon's diversity index (I = 0.598) was relatively high as compared with those of the other plant species. For ex situ genetic conservation of B. racemosa var. magna, the sampling strategy based on spatial autocorrelation using Tanimoto distance is efficient at choosing the conserved individuals with a 6 meter interval between individual trees.

• Korean Journal of Plant Resources
• /
• v.19 no.1
• /
• pp.189-195
• /
• 2006

We investigated the genetic variation in Stewartia koreana Nakai by examining 61 I-SSR amplicons in 120 individuals distributed among six natural populations in Korea. The overall percentage of polymorphic I-SSR amplicons was 81.9% and mean number of amplicons per I-SSR primer was 12.2. Levels of genetic diversity within 6 populations were similar each other[Shannon's Index $0.358{\sim}0.467$(mean: 0.407)]. The Mt. Obong population had the highest level of genetic diversity and was most distinctive from the other populations. Most variation existed among individuals within population(88.2%). Genetic differentiation among populations(${\phi}_{ST}$) was 0.118. The UPGMA dendrogram based on the genetic distance failed in showing decisive geographic relationships.

• Journal of Korean Society of Forest Science
• /
• v.98 no.1
• /
• pp.1-7
• /
• 2009

We investigated the genetic variation and structure in Korean Arborvitae (Thuja koraiensis Nak.), by 29 examining I-SSR polymorphic loci in 84 individuals distributed among four natural populations in Korea. The level of population genetic diversity ($A_e$=1.44, P=72.42, $H_e$=0.258, S.I.=0.385) was similar to or slightly higher than that of plants with similar ecological traits and life history (Cupressaceae). Most genetic diversity was allocated among individuals within populations (${\Phi}_{ST}$=0.13). The UPGMA dendrogram based on genetic distance failed in showing decisive geographic relationship. The Mt. Bangtae population had the lowest level of genetic diversity and was the most distinctive from the other populations. Mt. Jang population which is possessed of the highest level of genetic variation and Mt. Bangtae population which is consisted of heterogeneous was considered to be a prime candidate for the conservation studies.

• Journal of Korean Society of Forest Science
• /
• v.94 no.4 s.161
• /
• pp.209-213
• /
• 2005

In order to provide the molecular genetic information necessary for conservation of bog whortleberry (Vaccinium uliginosum L), one of the rare species in Korea, I-SSR analysis was performed on two populations on Mt. Halla and Mt. Seorak. A total of 68 I-SSR products were observed, and higher level of genetic diversity was observed in Mt. Halla population (S.I.=0.539) than in the Mt. Seorak population (S.I,=0.401). Level of genetic diversity in this species was relatively higher than those in other rare species analysed with I-SSR marker. From the results of AMOVA, exceptionally large proportion of genetic diversity (33.5%) was resulted from genetic difference between two populations, and only 66.5% of the genetic variation was allocated in common among individuals within each population, compared with the results in other long-lived woody species. This remarkably high degree of genetic heterogeneity existed between Mt. Halla and Mt. Seorak populations might suggest that they might be originated from the independent progenitors before the post glacier ages, respectively, and/or that they undergone random genetic drift respectively due to geographical isolation resulted from dramatic changes in environmental conditions after the post glacier ages.

• Journal of Korean Society of Forest Science
• /
• v.89 no.2
• /
• pp.167-172
• /
• 2000

Inter-simple sequence repeat (I-SSR) markers were analyzed from diploid genomes of 95 nutmeg trees (Torreya nucifera Siev. et Zucc.) in 5 populations. A total of 62 I-SSR amplicons were observed and 7 of them were monomorphic in 95 individuals. DNA fingerprint of each tree was verified by pooling the observed I-SSR amplicons. Most of the genetic diversity was allocated within population (90.65%) and all the populations revealed similar level of I-SSR amplicon diversity within population. Degree of population differentiation (${\phi}_{ST}=9.35%$) was moderate on the basis of criteria obtained from isozyme analysis. Based on the results of the cluster analysis of UPGMA, genetic relationships among 5 populations were not coincided with the pattern of geographic distribution. Non-significant confidence interval at each node also suggests that all the nutmeg populations are genetically not much differentiated.

• Journal of Korean Society of Forest Science
• /
• v.103 no.1
• /
• pp.59-64
• /
• 2014

This study describes analysis of genetic diversity and spatial genetic structure of Korean poplar (Populus koreana Rehder) in Mt. Odae using I-SSR markers. P. koreana is a deciduous broad-leaved tree species that primarily grows in the alpine valleys of China, Russia and North Korea. In South Korea, P. koreana is found limitedly in Gangwon province. Especially, the population in Mt. Odae is located on the southern limit line, its importance is emphasized from the genetic resource conservation perspective. The Shannon's diversity (I=0.230) and the expected heterozygosity (He=0.151) were relatively low as compared with those of other plant species. Spatial autocorrelation analysis using Tanimoto's distance showed that the genetic patch was founded within 400 m. It is suggested that individual trees for ex situ conservation should be sampled with a minimum distance of 400 m between trees.