• Journal of Crop Science and Biotechnology
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• 제11권4호
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• pp.263-268
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• 2008

Bacterial leaf pustule (BLP) caused by Xanthomonas axonopodis pv. glycines is a serious disease to make pustule and chlorotic haloes in soybean [Glycine max (L). Merr.]. While inheritance mode and map positions of the BLP resistance gene, rxp are known, no sequence information of the gene was reported. In this study, we made five near isogenic lines (NILs) from separate backcrosses (BCs) of BLP-susceptible Hwangkeumkong $\times$ BLP-resistant SS2-2 (HS) and BLP-susceptible Taekwangkong$\times$ SS2-2 (TS) through foreground and background selection based on the four-stage selection strategy. First, 15 BC individuals were selected through foreground selection using the simple sequence repeat (SSR) markers Satt486 and Satt372 flanking the rxp gene. Among them, 11 BC plants showed the BLP-resistant response. The HS and TS lines chosen in foreground selection were again screened by background selection using 118 and 90 SSR markers across all chromosomes, respectively. Eventually, five individuals showing greater than 90% recurrent parent genome content were selected in both HS and TS lines. These NILs will be a unique biological material to characterize the rxp gene.

• 한국육종학회지
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• 제40권3호
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• pp.223-227
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• 2008

In rice, tillering is an important trait determining yield. To study tillering at the agricultural and molecular aspects, we have examined a spontaneous rice mutant that showed reduction in the number of culms. The mutant was derived from a $F^6$ line of the cross of Junambyeo*4 / IR72. It could produce, on average, 4 tillers per hill in the paddy field while wild-type plants usually have 15. Except the reduced culm numbers, they also show pale green phenotypes. The phenotypes of this mutant were co-segregated as the monogenic Mendelian ratio (${\chi}^b=0.002$, p=0.969). In order to locate a gene responsible for the rcn phenotype, the mutant with the japonica genetic background was crossed with Milyang21 of the indica background. Bulked segregant analysis was used for rapid determination of chromosomal location. Three SSR markers (RM551, RM8213, and RM16467) on chromosome 4 were genetically associated with the mutant phenotype. Each of the 217 $F_2$ plants was genotyped with simple sequence length polymorphisms. The data showed that RM16572 on chromosome 4 was the closest marker that showed perfect co-segregation among the $F_2$ population. We suggest the new rcn gene studied here name as $rcn10^t$ because there was no report which exhibit a rcn phenotype with a pleiotropic effect of pale green (chlorophyll deficiency), and mapped at same position on chromosome 4.

• 한국육종학회지
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• 제42권5호
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• pp.470-480
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• 2010

The objectives of this study were to identify QTLs for agronomic traits using introgression lines from a cross between a japonica weedy rice and a Tongil-type rice. A total of 75 introgression lines developed in the Tongil-type rice were characterized. A total of 368 introgressed segments including 285 homozygous and 83 heterozygous loci were detected on 12 chromosomes based on the genotypes of 136 SSR markers. Each of 75 introgression lines contained 0-9 homozygous and 0-8 heterozygous introgressed segments with an average of 5.8 segments per line. A total of 31 quantitative and 2 qualitative loci were identified for 14 agronomic traits and each QTL explained 4.1% to 76.6% of the phenotypic variance. Some QTLs were clustered in a few chromosomal regions. A first cluster was located near RM315 and RM472 on chromosome 1 with QTLs for 1,000 grain weight, culm length, grain width and thickness. Another cluster was detected with four QTLs for 1,000 grain weight, grain length, grain width and grain length/width ratio near the SSR marker RM249 on chromosome 5. Among the 31 QTLs, 9 (28.1%) Hapcheonaengmi3 alleles were beneficial in the Milyang23 background. ILs would be useful to confirm QTLs putatively detected in a primary mapping population for complex traits and serve as a starting point for map-based cloning of the QTLs. Additional backcrosses are being made to purify nearly isogenic lines (NILs) harboring a few favorable Hapcheonaengmi3 alleles in Milyang23 background.

• 원예과학기술지
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• 제28권4호
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• pp.618-626
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• 2010

장미속 종간교잡 후대에서 발견되는 경모유전(matroclinal inheritance) 현상은 세포질 유전, 단위결과, 그리고 비대합적 배우자생식(asynaptic heterogamy)의 결과로 설명될 수 있다. 비대합적 배우자생식은 $Caninae$ 아절($Rosa$ $hybrida$ L. sect. $Caninae$ DC.)의 종간교잡에서 독특하게 관찰되며, 5배체의 경우, 화분세포를 통해서는 2가염색체(2x=14)를 이루는 상동게놈 중 한 게놈(x=7)만이, 난세포에서는 이러한 게놈(x=7)과 더불어 1가 염색체를 이루는 나머지 게놈들(3x=21)이 동시에 유전되어 후대에서 종자친의 배수성(5x=35)이 회복된다. 본 연구에서는 절화장미 품종간 정역교배시 대립유전자의 후대유전 빈도를 관찰함으로써, 4배체 품종교배에서 관찰되는 경모유전의 요인을 분석하고자 하였다. 절화장미 6품종을 이용한 6개 정역교배조합 당 8개의 후대개체를 총 30개의 EST-SSR 마커로 검정해 본 결과, 뚜렷한 세포질 유전의 경우는 발견되지 않았다. 또한, 단위결과의 경우도 'Redtem' ${\times}$ 'Red Sandra' 조합의 후대개체 하나에서만 발견되어, $Caninae$ 아절의 종간교잡에서와 비교하여 상당히 낮은 빈도였다. 비대합적 배우자생식의 예도 $Caninae$ 아절의 경우처럼 뚜렷하게 나타나지는 않았다. 하지만, 6개 공시품종 중, 4개의 품종에서 화분친 보다 종자친으로 교배시 품종 특이적 마커의 후대유전빈도가 상대적으로 높게 나타나 품종에 따라 대립유전자의 모계유전적 성향이 존재함을 증명하였다. 특히 'Yellow King'의 경우, 11개의 대립유전자 중 10개가 종자친일 경우에 후대집단에서 높은 빈도로 나타나 공시품종 중 가장 강한 모계유전성을 보였다.

• 한국작물학회지
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• 제60권4호
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• pp.448-457
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• 2015

다양한 가공제품을 개발하여 쌀 소비를 확대시키기 위하여 가공용도에 적합한 물성을 지닌 벼 품종을 개발하려는 노력이 계속되고 있는데, 특히 중간찰은 현미밥, 떡, 과자, 식혜, 술 등 다양한 가공식품 소재로 이용성이 높다. 국립식량과학원에서는 조생, 다수성 품종인 '남일'에 돌연변이원으로 아지드화나트륨을 처리하여 다수의 배유변이 계통을 확보한바 있다. 본 연구는 중간찰 특성을 발현하는 'Namil(SA)-dull1'의 작물학적 특성을 평가하고 아밀로스 함량을 지배하는 주동유전자위의 염색체상 위치를 규명하고자 수행되었다. 주요 결과는 아래와 같다. 1. 생산력 시험을 통해 'Namil(SA)-dull1'의 주요 작물학적 특성을 평가한 결과, 원품종인 '남일'에 비해 출수는 약 9일정도 늦은 중생종으로 간장과 수당립수가 유의하게 증가하였으나, 수수와 천립중은 다소 감소하여 수량성은 다소 낮게 평가되었다. 2. 'Namil(SA)-dull1'과 통일형인 '밀양23호'와의 교잡에서 유래한 94개 $F_2$ 개체로 구성된 유전분석집단에 대해 53개 SSR 마커의 유전자형을 검정하고, $F_{2:3}$ 종자의 아밀로스 함량을 조사하여 연관성분석(association analysis)를 수행한 결과 목표 유전자위는 염색체 6번 하단으로 추정되었다. 3. 염색체 6번 하단부위의 분자표지 밀도를 높이기 위하여 8개 SSR 마커를 추가로 배치하여 연관성분석을 수행한 결과, 염색체 6번 하단을 표지하는 RM7555의 유전자형변이가 유전분석집단의 아밀로스 함량변이의 81%를 설명한다는 것을 확인하였다. 4. 유전자지도 작성에 사용된 분자표지들이 표지하는 염색체 부위를 벼 전장유전체정보(rice pseudomolecule)에서 확인한 결과, 중간찰 특성을 지배하는 유전자위를 염색체 6번 28.95~29.89 Mbp 영역에 해당하는 약 0.94 Mbp 절편으로 제한할 수 있었으며, 향후 추가분리집단을 이용하여 목표 유전자를 동정하고 다양한 아밀로스 함량을 지니는 벼 신품종 육성의 효율성을 제고할 수 있는 초정밀분자표지를 개발할 계획이다.

• Journal of Plant Biotechnology
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• 제5권4호
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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.

• 식물조직배양학회지
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• 제28권3호
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• pp.129-134
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• 2001

Winter bud explants from 15 individual angelica tree (Aralia elata) were cultured in vitro to find out optimal conditions for somatic embryo induction as well as plant regeneration. Calli are induced and grown on MS medium supplemented with 1.0 mg/L 2,4-D for 4 weeks and subcultured on a half-strength MS medium without phytohormones to induce somatic embryos. Inter-simple sequence repeat (I-SSR) markers were analyzed with total DNAs extracted from the trees. Genotype effects on somatic embryo induction were examined by cluster analysis. Callus induction rate varied from 58.5 to 100% among the genotypes. Somatic embryo induction rate also greatly varied from 0 to 100% among the genotypes. There was a significant difference in somatic embryo induction rate even among the individual trees that showed close genetic relationships each other. This suggested that somatic embryo induction rate in Aralia elata be influenced by a few major specific genes rather than whole genomic similarity among individual trees. Four individuals of Ulneong-7, Cheju-1, Shingu and China, which are recalcitrant to somatic embryo induction, turned out to have a close genetic relationship, suggesting that both physiological and genetic factors affect somatic embryo induction. The results suggest that genotype selection be the most important factor to achieve an efficient propagation, although cultural optimization through medium and explant manipulation may also play crucial roles in somatic embryogensis as well as plant regeneration of these species.

• 한국산림과학회지
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• 제98권5호
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• pp.568-575
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• 2009

Korean wild and forest cultivated ginseng has long been accepted as high medicinal values compared to field cultivated ginseng. Owing to the high price of Korean wild ginseng, Chinese wild and forest cultivated ginseng were smuggled and sold as Korean wild and forest cultivated ginseng. Therefore, an efficient method is required to distinguish Korean ginseng from Chinese ginseng. Microsatellites, simple sequence repeats (SSRs), are highly polymorphic loci present in DNA that consist of repeating units of base pairs. Thus SSR markers are highly advantageous for detection of small genetic variances of intra-species. In the present study, we constructed a microsatellite-enriched genomic library from South Korean wild Panax ginseng. After sequence analysis of 992 randomly picked positive colonies, 126 (12.7%) of the colonies were found to contain microsatellite sequences, and 38 primer pairs were designed. By polymorphism assessment using 36 primer pairs, 4 primers (PG409, PG450, PG491, and PG582) were shown to be polymorphic to distinguish the South Korean ginseng from the Chinese ginseng. These 4 microsatellite markers will provide powerful tools to authenticate South Korean ginseng from Chinese ginseng.

• Journal of Crop Science and Biotechnology
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• 제11권3호
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• pp.163-170
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• 2008

The detection, characterization and use of quantitative traits loci, QTL, have significant potential to improve the efficiency of selective breeding of species. Therefore, a population with 59 advanced backcross lines($BC_2F_5$), derived from a cross between IR64 and Tarome molaei, were studied in Tonekabon Rice Research Station of Iran in order to map QTLs for panicle length, number of grain per panicle, and panicle grain sterility in rice. The parental screening wtih 235 SSR markers in agarose and polyacrylamide gels revealed 114 markers with clear polymorphic bands. To search for QTLs associated with panicle length, number of grain per panicle, and panicle grain sterility, we constructed a genetic linkage map using 114 microsatellite markers. Positive and negative transgressive segregations were observed in $BC_2F_5$ lines for all traits. Using multiple interval mapping(MIM), a total of 20 putative QTLs were detected, of which eight were for panicle length, three for number of grains, and nine for panicle grain sterility. The maximum number of QTLs were mapped on chromosomes 1 and 2 with eight QTLs. These QTL markers could possible be utilized for marker-assisted selection.

• Journal of Crop Science and Biotechnology
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• 제11권3호
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• pp.171-176
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• 2008

The agronomic traits, such as days to flowering and maturity, plant height, 100-seed weight and seed filling period, are quantitatively inherited and important characters in soybean(Glycine max L. Merr.). A total of 126 $F_5$ recombinant inbred lines(RILs) developed from the cross of PI 171451$\times$Hwaeomputkong were used to identify quantitative trait loci(QTLs) for days to flowering(FD), days to maturity(MD), plant height(PH), 100-seed weight(SW), number of branches(NB) and seed filling period(FP). A total of 136 simple sequence repeat(SSR) markers segregated in a RIL population were distributed over 20 linkage groups(LGs), covering 1073.9 cM of the soybean genome with the average distance between adjacent markers of 7.9 cM. Five independent QTLs were identified for FD, three for MD, two for PH, three for SW, one for NB and one for FP. Of these, three QTLs were related to more than two traits of FD, MD, PH, NB and FP and mapped near the same positions on LGs H and O. Thus, these traits could be correlated with biologically controlled major QTLs in this soybean RIL population.