• 한국약용작물학회지
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• 제13권1호
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• pp.48-51
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• 2005

보호식물이며, 약용식물인 깽깽이풀 (Jeffersonia dubia)을 대상으로 핵형 분석과 McFISH 기법을 이용한 염색체 분석을 수행하여 다음과 같은 결과를 얻었다. 체세포 염색체 수는 2n=2x=12였으며, 2쌍의 중부 염색체 (염색체 1, 3), 2쌍의 차중부 염색체 (염색체 2, 4) 그리고 2쌍의 차단부 염색체 (염색체 5, 6)로 구분되었고, 염색체의 평균 길이는 $1.95{\sim}3.50{\mu}M$이었다. McFISH기법을 이용하여 45S와 5S rDNA의 염색체상의 위치를 확인한 바, 3쌍의 45S rDNA signal은 4번, 5번 그리고 6번 염색체의 단완 말단 부위에서 관찰되었고, 한 쌍의 5S rDNA signal은 2번 염색체의 동원체 부위에서 관찰되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1999년도 춘계 학술대회지
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• pp.162-163
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• 1999

The goal of this research was (1) to describe the conditions and parameters required for the cell cycle synchronization and the accumulation of large number of metaphase cells in maize and other cereal root tips, (2) to isolate intact metaphase chromosomes from root tips suitable for characterization by flow cytometry, and (3) to construct chromosome-specific libraries from maize. Plant metaphase chromosomes have been successfully synchronized and isolated from many cereal root-tips. DNA synthesis inhibitor (hydroxyurea) was used to synchronize cell cycle, follwed by treatement with trifluralin to accumulate metaphase chromosomes. Maize flow karyotypes show substantial variation among inbred lines. thish variation should be sueful in isolating individual chromosome types. In addition, flow cytometry is a useful method to measure DNA content of individual chromosomes in a genotyps, and to detect chromosomal variations. Individual chromosome peaks have been sorted from the maize hybrid B73/Mol7. Libraries were generated form the DOP-PCR amplification product from each peak. To date, we have analyzed clones from a library constructed from the maize chromosome 1 peak. Hybridization of labeled genomic DNA to clone inserts indicated that $24\%,\;18\%,\;and\;58\%$ of the clones were highly repetitive, medium repetitive, and low copy, respectively. Fifty percent of putative low cpoy clones showed single bands on inbred screening, blots, and the remaining $50\%$ were low copy repeats. Single copy clones showing polymorphism will be mapped using recombinant inbred mapping populations. Repetitive clones are being characterized by Southern blot analysis, and will be screened by in situ hybridization for their potential utility as chromosome specific markers.

• 한국육종학회지
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• 제41권4호
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• pp.429-436
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• 2009

We conducted a QTL analysis of grain quality traits using 117 $BC_3F_4$ and $BC_3F_5$ lines developed from a cross between Ilpumbyeo and Moroberekan. Genotypes of 117 $BC_3F_5$ lines were determined using 134 simple sequence repeat (SSR) markers. A linkage map constructed using 134 SSR markers was employed to characterize quantitative trait loci (QTL). The 117 $BC_3F_4$ and $BC_3F_5$ lines were evaluated for eleven grain quality traits in 2005 and 2006. A total of 18 QTLs were identified for eleven traits, and the phenotypic variance explained by each QTL ranged from 9.9% to 35.2%. Moroberekan alleles contributed positive effects in the Ilpumbyeo background at two QTL loci for 1,000 grain weight. Four QTLs, two for chalky rice and one each for 1,000 grain weight and head rice were consistently detected in two consecutive years indicating that these QTLs are stable. Clusters of QTLs were observed in three chromosome regions. One cluster harboring five QTLs including head rice and brown rice ratio near SSR markers RM190 and RM314 was detected on chromosome 6. Another cluster harboring grain weight and white belly was detected on chromosome 2. Increase in white belly at this locus might be due to the increase in grain weight due to the presence of the Moroberekan allele. The Moroberekan alleles at two QTL loci, gw3 and gw4 associated with increased grain weight might be useful in breeding programs to develop high-yielding cultivars.

• Forest Science and Technology
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• 제14권4호
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• pp.181-191
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• 2018

This study was carried out in the teaching and research forest of the University of Dschang in Belabo, with the aim of analysing land-cover and land-use changes as well as carbon stocks dynamic. The databases used are composed of three Landsat satellite images (5TM of 1984, 7ETM + of 2000 and 8OLI of 2016), enhanced by field missions. Satellite images were processed using ENVI and ArcGIS software. Interview, focus group discussion methods and participatory mapping were used to identify the activities carried out by the local population. An inventory design consisting of four transects was used to measure dendrometric parameters and to identify land-use types. An estimation of carbon stocks in aboveground and underground woody biomass was made using allometric models based on non-destructive method. Dynamic of land-cover showed that the average annual rate of deforestation is 0.48%. The main activities at the base of this change are agriculture, house built-up and logging. Seven types of land-use were identified; adult secondary forests (64.10%), young secondary forests (7.54%), wetlands (7.39%), fallows (3.63%), savannahs (9.59%), cocoa farms (4.28%) and mixed crop farms (3.47%). Adult secondary forests had the highest amount of carbon ($250.75\;t\;C\;ha^{-1}$). This value has decreased by more than 60% for mixed crop farms ($94.67\;t\;C\;ha^{-1}$), showing the impact of agricultural activities on both forest cover and carbon stocks. Agroforestry systems that allow conservation and introduction of woody species should be encouraged as part of a participatory management strategy of this forest.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.201-201
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• 2022

Rice bakanae disease is a serious global threat in major rice-cultivating regions worldwide causing high yield loss. It is caused by the fungal pathogen Fusarium fujikuroi. Varying degree of resistance or susceptibility to bakanae disease had been reported among Korean japonica rice varieties. We developed a modified in vitro bakanae disease bioassay method and tested 31 Korean japonica rice varieties. Nampyeong and Samgwang varieties showed highest resistance while 14 varieties including Junam and Hopum were highly susceptible with 100% mortality rate. We carried out mapping QTLs for bakanae disease resistance with four F2:F3 populations derived from the crosses between Korean japonica rice varieties. The Kompetitive Allele-Specific PCR (KASP) markers developed in our laboratory based on the SNPs detected in Korean japonica rice varieties were used in genotyping F2 plants in the populations. We found four major QTLs on chromosome 1, 4, 6, and 9 with LOD scores of 21.4, 6.9, 6.0, and 60.3, respectively. In addition, we are doing map-based cloning of the QTLs on chromosome 1 and 9 which were found with Junam/Nampyeong F2:F3 population and Junam/Samgwang F2:F3 population, respectively. These QTLs will be very useful in developing bakanae disease resistant high quality rice varieties.

• 한국육종학회지
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• 제50권4호
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• pp.387-395
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• 2018

다산 등 15개의 통일형 벼 품종을 이용하여 mesotrione을 처리한 후 5일부터 다산 등 13개 품종들은 신엽에서 백화현상이 발생하였으나, 밀양154호와 수원382호는 백화현상이 발생하지 않아 저항성 품종으로 선발되었다. Mesotrione 처리 후 다산 등 13개 품종들의 초장 및 건물중 억제율은 밀양154호와 수원382호보다 더 높았으며 약량에 따른 억제율이 증가하였다. 한아름2호/밀양154호의 $F_2$ 집단을 이용한 유전분석 결과 저항성이 149개체, 감수성이 41개체로 이론적 분리비 3:1($X^2=1.19$, P=0.31)에 적합하여, mesotrione 저항성 관련 유전자는 1개의 우성유전자에 지배되는 것으로 나타났다. BSA방법을 이용하여 mesotrione 저항성 관련 유전자를 탐색한 결과, 2번 염색체의 10.2 Mb에 위치한 SSR marker RM1358과 RM3501을 선발하였다. Fine mapping을 위해 선발된 5개의 저항성 개체 중에서 $F_2-137$은 RM12921부터 RM3501까지 재조환이 일어났고, $F_2-76$은 RM324부터 RM5101까지 재조환이 일어났다. 따라서, mesotrione 저항성 관련 유전자는 RM3501과 RM324 사이인 10.2 Mb~11.4 Mb에 존재하며, RM3501과 RM324의 조환률이 각각 0.53%과 2.65%이므로, RM3501을 mesotrione저항성 유전자 DNA 연관 marker로 선발하였다. 다산 등 20개 통일형 품종 및 mesotrione에 저항성을 나타내는 자포니카 품종인 운광과 감수성인 통일형 한아름의 $BC_2F_2$ 집단을 이용하여 RM3501의 MAS 이용 가능성을 검토한 결과, mesotrione 저항성 선발 marker로 활용은 가능하나, 정확한 선발 maker로 활용하기 위해서는 추가적인 실험이 필요할 것으로 판단된다.

• 한국육종학회지
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• 제51권4호
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• pp.395-403
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• 2019

우리나라의 도열병 균계에 내구저항성을 보이는 자포니카 벼 품종 팔공의 저항성 유전좌위를 분석한 결과, 팔공 allele에 의한 저항성 관련 putative QTLs가 2번, 4번, 7번, 11번 염색체상에서 9개 좌위들이 확인되었다. 팔공의 allele에 의한 도열병 저항성 연관 유전자좌들 중 qBn2.3 (Ch r. 2), qBn4.2 (Ch r. 4), qBn11.1 및 qBn11.2 (Ch r. 11) 등 4개 좌위는 표현형 변이의 28-56.7%를 설명하는 major QTL이었고, 이들 좌위에서는 1-4개의 저항성 관련 유전자들이 위치하는 것으로 보고되었다. 팔공 allele의 5개 QTLs qBn2.1, qBn2.4 (Ch r. 2), qBn4.1 (Chr. 4), qBn7.1 및 qBn7.2 (Ch r. 7) 등은 표현형 변이를 9.7-18.8% 설명하였으며, 이들 좌위들 중 2번 염색체상의 qBn2.1를 제외한 4개 QTLs 좌위에서는 다른 유전자의 보고가 없어 팔공 고유의 도열병 저항성 관련 유전 요소들로 추정 된다. 팔공의 도열병 내구 저항성은 2번, 4번, 7번, 11번 염색체상의 9개 QTLs들의 상호 작용에 의한 것으로 생각되며, 특히 목도열병 내구 저항성 유전자 Pb1이 위치하는 것으로 보고된 좌위의 qBn11.2는 표현형 변이 56.7%를 설명하였고 내구저항성에서 중요한 역할을 하는 것으로 생각된다. 팔공의 줄무늬잎마름병 저항성은 qBn11.2 좌위의 Stvb-i 유전자에 의한 것으로 생각된다.

• Plant Biotechnology Reports
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• 제4권1호
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• pp.61-73
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• 2010

Quantitative trait loci (QTL) associated with six physical traits of cooked rice and seven chemical properties of rice grain were identified using a recombinant inbred (RI) population of rice evaluated over 3 years at the National Honam Agricultural Research Institute in Korea. The RI population consisted of 164 lines derived from a cross between Milyang23 and Gihobyeo, and the genetic map consisted of 414 molecular markers. A total of 49 QTL were identified for the 13 physico-chemical properties using composite interval mapping. Of these, 13 QTL were identified for 2 or more years, while 36 were detected in only 1 year. Five QTL were identified over all 3 years and will be useful for marker-assisted improvement of rice grain quality in Korea. The two QTL with the highest LOD scores, adhesiveness1.2 and potassium content7.1, provide a valuable starting point for positional cloning of genes underlying these QTL.

• 한국기계가공학회지
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• 제18권8호
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• pp.98-103
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• 2019

A more accurate method of feature point extraction and matching for three-dimensional reconstruction using low-resolution images of crops is proposed herein. This method is important in basic computer vision. In addition to three-dimensional reconstruction from exact matching, map-making and camera location information such as simultaneous localization and mapping can be calculated. The results of this study suggest applicable methods for low-resolution images that produce accurate results. This is expected to contribute to a system that measures crop growth condition.

• The Plant Pathology Journal
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• 제37권1호
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• pp.1-23
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• 2021

Resistance to diseases caused by turnip mosaic virus (TuMV) in crop species of the family Brassicaceae has been studied extensively, especially in members of the genus Brassica. The variation in response observed on resistant and susceptible plants inoculated with different isolates of TuMV is due to a combination of the variation in the plant resistome and the variation in the virus genome. Here, we review the breadth of this variation, both at the level of variation in TuMV sequences, with one eye towards the phylogeny and evolution of the virus, and another eye towards the nature of the various responses observed in susceptible vs. different types of resistance responses. The analyses of the viral genomes allowed comparisons of pathotyped viruses on particular indicator hosts to produce clusters of host types, while the inclusion of phylogeny data and geographic location allowed the formation of the host/geographic cluster groups, the derivation of both of which are presented here. Various studies on resistance determination in particular brassica crops sometimes led to further genetic studies, in many cases to include the mapping of genes, and in some cases to the actual identification of the genes. In addition to summarizing the results from such studies done in brassica crops, as well as in radish and Arabidopsis (the latter as a potential source of candidate genes for brassica and radish), we also summarize work done using nonconventional approaches to obtaining resistance to TuMV.