• 한국연초학회지
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• 제18권2호
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• pp.126-131
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• 1996

In this study effects of isolation distance, transplanting time of maternal plants, and bagging of flower head with the gauze-cloth bag on the outcrossing of burley tobacco (Nicotiana tabacum L.) were investigated. Also the effect of fertilizer level and control of the number of capsules per plant on seed production and quality were examined. A male sterile line. produced 0.3 to 3.8 capsules Per plant when it was Planted with normally flowering tobacco with the average outcrossing of 7.2 plants, ranging from 2 to 18 out of 20 plants. With the farther the isolation distance between maternal plants and pollen donor plant, the lower the outcrossing occurred. Outcrossing occurred even at the isolation distance of 312 m. When the maternal plants were transplanted 35 days after transplanting the pollen donor ones, the outcrossed plants were not decreased significantly. The bagging of the flower head with the gauze-cloth bas (#0.9∼ 1.0 mm) decreased the outcrossed plants significantly, but couldn't prevent the outcrossing completely. The seed amount per plant was higher in the highly fertilized cultivation. The number of seed capsules per plant affected significantly on seed yield and quality. When the seed capsules was controlled by 30 or 50 capsules per plant, the weight of 1,000 seeds and germination rate were higher than those with 70 or 90 capsules per plant. Key words : Nicotiana tabacum, outcrossing, bagging.

• Journal of Ecology and Environment
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• 제29권5호
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• pp.411-414
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• 2006

The mating systems of two groups of natural populations of Gleditsia japonica var. koraiensis in Korea were determined using allozyme analysis. The result suggests that G. japonica var. koraiensis is predominantly outcrossing. The tm values of eight populations in Korea varied from 0.667 (Mdh-1) to 0.938 (ldh-1), giving an average 0.820. Population and individual outcrossing estimates were associated with flowering tree density or degree of spatial isolation. The reason for relatively low outcrossing rates of some populations could be attributed to reduction of effective population sizes of sib for the medicine, small population size, and isolation of flowering mature trees. The heterozygote excesses were observed in some natural populations, whereas other populations exhibited varying degrees of inbreeding and heterozygotes deficit. Thus, selection against homozygotes operated in the progeny populations throughout the life cycle.

• Journal of Ecology and Environment
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• 제30권3호
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• pp.225-229
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• 2007

The mating systems of natural populations of Potentilla freyniana in Korea were determined using allozyme analysis. The result suggests that P. freyniana is outcrossing as well as employing vegetative reproduction by stolon (self-fertilization rate, s < 0.5). The values of the inbreeding coefficient of eight populations in Korea varied from 0.244 to 0.331, with an average value of 0.274. For eight natural populations, multi-locus estimates of outcrossing (tm) was 0.603 across 13 polymorphic loci, with individual population values ranging from 0.530 to 0.652. The relatively low outcrossing rates of some populations could be attributed to extensive vegetative reproduction by stolon and the isolation of flowering mature plants. Although P. freyniana usually propagated by asexually-produced ramets, I could not rule out the possibility that sexual reproduction occurred at a low rate because each ramet may produce terminal flowers. Although heterozygote excess was observed in some natural populations, most populations exhibited varying degrees of inbreeding and a heterozygote deficit.

• 한국자원식물학회지
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• 제25권1호
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• pp.63-71
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• 2012

To assess parameters of mating system in seed orchard, such as outcrossing rates, number of potential pollen contributors, and degree of pollen contamination, seeds, produced in '77 plot of the Japanese red pine (Pinus densiflora S et Z) seed orchard at Anmyeon island, were collected in 2007 and analysed by nSSR and cpSSR markers. Estimates of outcrossing rates ranged from 91.2 to 100% (mean 97.7%) on the basis of the analysis of cpSSR haplotypes and from 81.6 to 100% (mean 95.3%) on the basis of the analysis of nSSR genotypes. By cross checking of both DNA markers, seeds, presumed to be products of self pollination on the basis of single marker, were confirmed as outcrossed seeds, which resulted in cumulative outcrossing rates of 98.9%. On the basis of pooled cpSSR haplotype of each seed, the number of pollen contributors and paternal contribution rates were estimated as 14.8 and 0.512, respectively. In conclusion, considering pretty high level of outcrossing rates observed in a seed orchard, good genetic potential of the seeds, produced in '77 plot of the seed orchard of Japanese red pines at Anmyeon island, may be guaranteed. Investigated results from the analysis of mating system of Japanese red pines in a '77 plot of the seed orchard may also be expected to provide useful information for the management and establishment of the seed orchard of the progressive generation.

• 생명과학회지
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• 제17권11호
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• pp.1477-1481
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• 2007

한국 내 얼치기완두(Vicia tetrasperm) 집단의 교배계를 알로자임 분석으로 실시하였다. 그 결과 얼치기완두는 타가수분 또는 혼합 교배 타가수분을 영위하고 있었다. 집단 수준에서 열 개 집단에 대한 내교배 계수는 0.131에서 0.176까지로 나타나며 평균은 0.154였다. 다대립좌위에서 타가수분 계수(tm)는 열 개 집단에 대해 0.269와 0.423사이에 있으며 평균은 0.333이었다. 다대립좌위와 단일좌위에서 타가수분 계수 차이는 상당히 높게 나타났으며 양친과의 근친교배가 유의하게 일어나고 있었다. 일부 집단에서 낮은 타가수분율은 광범위한 근친교배와 성숙한 개체간 격리에 기인한다. 비록 한 집단에서 이형접합체 과다가 기록되었지만 대부분 집단은 이형접합체의 결핍이 관찰되었다. 따라서 동형접합체에 대한 자연선택이 생활사를 통한 지손집단에 작용하고 있었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.57-57
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• 2017

Chrysanthemum is one of the most important floral crop in Korea produced about 7 billion dollars (1 billion for pot and 6 billion for cutting) in 2013. However, it is difficult to breed and to do genetic study because 1) it is highly self-incompatible, 2) it is outcrossing crop having heterozygotes, and 3) commercial cultvars are hexaploid (2n = 6x = 54). Although low-density genetic map and QTL study were reported, it is not enough to apply for the marker assisted selection and other genetic studies. Therefore, we are trying to make high-density genetic mapping using GBS with about 100 $F_1s$ of C. boreale that is oHohhfd diploid (2n = 2x = 18, about 2.8Gb) instead of commercial culitvars. Since Chrysanthemum is outcrossing, two-way pseudo-testcross model would be used to construct genetic map. Also, genotype-by-sequencing (GBS) would be utilized to generate sufficient number of markers and to maximize genomic representation in a cost effective manner. Those completed sequences would be analyzed with TASSEL-GBS pipeline. In order to reduce sequence error, only first 64 sequences, which have almost zero percent error, would be incorporated in the pipeline for the analysis. In addition, to reduce errors that is common in heterozygotes crops caused by low coverage, two rare cutters (NsiI and MseI) were used to increase sequence depth. Maskov algorithm would also used to deal with missing data. Further, sparsely placed markers on the physical map would be used as anchors to overcome problems caused by low coverage. For this purpose, were generated from transcriptome of Chrysanthemum using MISA program. Among those, 10 simple sequence repeat (SSR) markers, which are evenly distributed along each chromosome and polymorphic between two parents, would be selected.

• 한국산림과학회지
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• 제99권3호
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• pp.344-352
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• 2010

소나무 채종원내 클론 간 교배양식을 구명하기 위해서 4개의 nSSR 표지와 6개의 cpSSR 표지를 이용하여 소나무 채종원 내에서의 타가교배율, 기여 화분친 수, 화분오염율을 산출하였다. cpSSR haplotype에 근거한 타가교배율은 94~100%로, 평균 98.9%의 타가교배율이 산출되었다. nSSR genotype에 근거한 타가교배율은 90.3~100%로, 평균 95.9%의 타가교배율이 산출되었다. 별개의 DNA 표지분석에서 자가교배로 확인 되었던 종자들을 두 표지를 동시에 비교하여 확인한 결과 타가교배 종자로 최종 확인되었다(누적 타가교배율 100%). 화분오염율은 최소 43.6%(강원10)에서 최대 56.4%(강원12)로 평균 48.9%로 계산되었다. 종자의 cpSSR haplotype을 근거로 확인한 기여 화분친은 경북38에서 21개로 최대치가 확인되었으며, 강원10에서 13개로 최소치가 확인되어 평균 16.2개의 기여 화분친이 확인되었다. 결론적으로, 안면도 소나무 채종원 ’77단지내 클론간 높은 타가교배율이 확인됨으로써 채종원산 종자의 유전적 안정성을 기대할 수 있으며, 안면도 소나무 채종원 '77단지 내 교배양식 분석을 통해서 확인된 결과가 향후 전진세대 채종원 조성 및 관리에 유용한 정보를 제공할 것으로 기대된다.

• 한국산림과학회지
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• 제102권2호
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• pp.264-271
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• 2013

설악산 권금성 일대에 분포하는 잣나무 자연집단을 대상으로 동위효소와 cpSSR 표지를 이용하여 교배양식을 추정하였다. 동위효소를 이용하여 교배양식 모수를 추정한 결과 다수유전자좌 타가교배율($t_m$)은 0.882, 단일유전자좌 타가교배율($t_s$)은 0.881, 부계상관($r_p$)은 0.368로 유효 화분친 수는 평균 2.7개였다. cpSSR 표지를 이용하여 교배양식 모수를 추정한 결과, 타가교배율은 평균 0.831이었으며 유효 화분친 수는 평균 12.4개였다. 두 표지 간 평균 타가 교배율은 0.857로 침엽수종들의 타가교배율과 비슷한 수준이었다. 화분친 수는 동위효소를 이용하여 추정된 결과에 비해 cpSSR 표지로 추정된 결과가 높게 나타나서 DNA 표지의 개체식별력이 동위효소 표지에 비해 교배양식 구명에서 상대적으로 화분친을 정확하게 추정하는데 유리한 것으로 판단되었다.

• Journal of Plant Biotechnology
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• 제34권1호
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• pp.47-53
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• 2007

To assess the risk of genetically modified (GM) rice on the agricultural ecosystem, agronomic characteristics, pollen longevity and outcrossing rate between GM (Iksan 483 and Milyang 204) and non-GM (their wild types and female parents) varieties were investigated using the bar gene as a tracer marker in paddy field. The agronomic characteristics of two GM rice were similar to their female-parents (non-GM rice) except heading date and 1,000 grain weight of Iksan 483, and they did not show a difference by the introgression of the bar gene as the genetic traits of rice varieties. Pollen viability was more than 90% just after shedding, and it was rapidly decreased below 50% at 5 minutes after shedding both GM and non-GM varieties. The Pollen longevity was lost after 30 minutes of anthesis. When the distance of gene flow from GM to non-GM rice detected to 6 m from the edge of GM rice plant, the maximum distance of pollen dispersal was 4.5m and 3.9m in Iksan 483 and Milyang 204, respectively, and that was increased in order of west, south, east, and north to the dominant wind direction, west-south. Mean outcrossing rate was very low as 0.003 and 0.001% within 1.5 m from the edge of Iksan 483 and Milyang 204, and the GM hybrids by the pollen dispersal did not detected over 4.5 m from the edge of GM rice plant. The results may help to establish the strategy which reduce the risk of pollen-mediated gene flow between GM and non-GM rice.

• 한국자원식물학회지
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• 제24권6호
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• pp.702-711
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• 2011

Buckwheat (Fagopyrum esculentum Moench), one of the minor crops grown in Korea belonging to the Polygonaceae family, is an annual crop widely cultivated in Asia, Europe, and America and has a character of outcrossing and self-incompatibility. The objective of this study was to analyze the genetic variability, phylogenetic relationships and population structure of buckwheat landraces of Korea using SSR markers. Ten microsatellite markers have been detected from a total of 79 alleles among the 179 buckwheat accessions were collected from Korea. The number of allele per marker locus ($N_A$) ranged from 2 (GB-FE-001, GB-FE-043 and GB-FE-055) to 31 (GB-FE-035) with an average of 7.9 alleles. GB-FE-035 was the most polymorphic with the highest PIC value 0.93. Major allele frequencies ($M_{AF}$) for the 10 polymorphic loci varied from 0.12 to 0.97 with a mean allele frequency of 0.57. The expected heterozygosity ($H_E$) values ranged from 0.05 to 0.94 with an average of 0.53. The observed heterozygosity ($H_O$) ranged from 0.06 to 0.92 with an average of 0.42. The overall polymorphic information contents (PIC) values ranged from 0.05 to 0.93 with an average of 0.48. The landrace accessions of buckwheat used in the present study were not distinctly grouped according to geographic distribution. The study concludes that the results revealed genetic differentiation was low according to the geographic region because of outcrossing and self-incompatibility. We reported that our analyses on the genetic diversity of common buckwheat cultivars of Korea were performed by using of microsatellite markers.