• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1066-1073
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• 2017

Objective: Growth-related traits are important economic traits in the swine industry. However, the genetic mechanism of growth-related traits is little known. The aim of this study was to screen the candidate genes and molecular markers associated with body dimension and body weight traits in pigs. Methods: A genome-wide association study (GWAS) on body dimension and body weight traits was performed in a White $Duroc{\times}Erhualian$ $F_2$ intercross by the illumina PorcineSNP60K Beadchip. A mixed linear model was used to assess the association between single nucleotide polymorphisms (SNPs) and the phenotypes. Results: In total, 611 and 79 SNPs were identified significantly associated with body dimension traits and body weight respectively. All SNPs but 62 were located into 23 genomic regions (quantitative trait loci, QTLs) on 14 autosomal and X chromosomes in Sus scrofa Build 10.2 assembly. Out of the 23 QTLs with the suggestive significance level ($5{\times}10^{-4}$), three QTLs exceeded the genome-wide significance threshold ($1.15{\times}10^{-6}$). Except the one on Sus scrofa chromosome (SSC) 7 which was reported previously all the QTLs are novel. In addition, we identified 5 promising candidate genes, including cell division cycle 7 for abdominal circumference, pleiomorphic adenoma gene 1 and neuropeptides B/W receptor 1 for both body weight and cannon bone circumference on SSC4, phosphoenolpyruvate carboxykinase 1, and bone morphogenetic protein 7 for hip circumference on SSC17. Conclusion: The results have not only demonstrated a number of potential genes/loci associated with the growth-related traits in pigs, but also laid a foundation for studying the genes' role and further identifying causative variants underlying these loci.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1061-1065
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• 2017

Objective: This study was conducted to locate quantitative trait loci (QTL) influencing fatty acid (FA) composition in a large $F_2$ intercross between Landrace and Korean native pigs. Methods: Eighteen FA composition traits were measured in more than 960 $F_2$ progeny. All experimental animals were genotyped with 165 microsatellite markers located throughout the pig autosomes. Results: We detected 112 QTLs for the FA composition; Forty seven QTLs reached the genome-wide significant threshold. In particular, we identified a cluster of highly significant QTLs for FA composition on SSC12. QTL for polyunsaturated fatty acid on pig chromosome 12 (F-value = 97.2 under additive and dominance model, nominal p-value $3.6{\times}10^{-39}$) accounted for 16.9% of phenotypic variance. In addition, four more QTLs for C18:1, C18:2, C20:4, and monounsaturated fatty acids on the similar position explained more than 10% of phenotypic variance. Conclusion: Our findings of a major QTL for FA composition presented here could provide helpful information to locate causative variants to improve meat quality traits in pigs.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.565-570
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• 2006

The viviparous germination (VG) with lodging caused the yield reduction and quality deterioration in rice. We carried out the evaluation of VG tolerance (on the 40th day after heading) and mapping QTLs associated with VG tolerance using the recombinant inbred lines (M/G RILs) from a cross between Milyang 23 (japonica/indica) and Gihobyeo (japonica). The VG rates of Milyang 23 and Gihobyeo were 0.0 and 7.0%, respectively. The averaged VG rate of 162 M/G RILs was 7.7%, and their range was from 0.0 to 50.9%. Of the 162 RILs, 144 lines were tolerant less than 10%, and 18 lines were susceptible more than 10%. Using the M/G RIL Map, three QTLs associated with the viviparous trait were detected on chromosome 2 (qVG 2-1 and qVG 2-2) and 8 (qVG 8). qVG 2-1 was linked to RM 32D and RZ 166, and had LOD score of 2.97. qVG 2-2 was tightly linked to E13M59.119-Pl and E13M59.M003-P2, and showed higher LOD score of 3.41. qVG 8 was linked to RM33 and TCT116, and had LOD score of 2.67. The total phenotypic variance explained by the three QTLs was about 24.4% of the total variance in the population. The detection of new QTLs associated with VG tolerance will provide important informations for the seed dormancy, low temperature germination, or comparative genetics.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.105-110
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• 2010

This study was conducted to analyze the relationships between resistance of brown planthopper and traits related to the lodging in rice. For the linkage analysis of traits tested in this study, a genetic linkage map was created with 162 DNA markers spanning 12 rice chromosomes based on 120 doubled haploid (DH) lines, which were derived from a cross between Samgang', a Tongil type cultivar with BPH resistance, and ‘Nagdong’, a japonica cultivar. QTLs were identified to analyze the agronomic traits including lodging by composite interval mapping. Thirteen QTLs were detected for five traits comprised of plant length (PL), 3rd internode length (3rdIL), moments (Mo), lodging index (LI), and breaking weight (BW). The relationships between the BPH resistance and agronomic traits including lodging revealed that two QTLs (qBPR7, qBPR8) were linked to traits related to lodging. Two QTLs, qBPR7 and qBPR8 on chromosome 7 (RM531-7042) and 8 (RM1148- RM544) showed associations with moments and 3rd internode length, respectively.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.1014-1024
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• 2010

Pepper ($Capsicum$ spp.) anthracnose caused by $Colletotrichum$ $acutatum$ is a destructive disease susceptible to areas where chili peppers are grown. $Capsicum$ $baccatum$ var. $pendulum$ (Cbp) is resistant to anthracnose and has actively been used for interspecific hybridization for the introgression of resistance gene(s) into cultivated chili peppers. The goals of this study were to determine the inheritance of resistance to anthracnose within $Capsicum$ $baccatum$ and to map quantitative trait loci (QTLs) for the anthracnose resistance. A genetic mapping population consisting of 126 $F_2$ plants derived from a cross between $Capsicum$ $baccatum$ var. $pendulum$ (resistant) and $Capsicum$ $baccatum$ 'Golden-aji' (susceptible) was used for linkage mapping. The linkage map was constructed with 52 SSRs, 175 AFLPs, and 100 SRAPs covering 1,896cM, with an average interval marker distance of 4.0cM. Based on this map, the number, location, and effect of QTLs for anthracnose resistance were studied using plants inoculated in the laboratory and field. A total of 19 quantitative trait loci (2 major QTLs and 16 minor QTLs) were detected. Two QTLs ($An8.1$, $An9.1$) showed 16.4% phenotypic variations for anthracnose resistance after wounding inoculation. In addition, five minor QTL loci ($An7.3$, $An7.4$, $An4.1$, $An3.1$, $An3.2$) showed a total of 60.73% phenotypic variations of anthracnose resistance in the field test. Several significant QTLs were also detected and their reproducibility was confirmed under different inoculation conditions. These QTLs are now being confirmed with different breeding populations. Markers tightly linked to the QTLs that are reliable under different environmental conditions will help to determine the success of marker-assisted selection for anthracnose -resistant breeding programs in chili pepper.

• Journal of IKEEE
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• v.23 no.2
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• pp.502-507
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• 2019

We investigated theoretically the quantum optical transition properties of qusi 2-Dinensinal Landau splitting system, in Si. We apply the Quantum Transport theory (QTR) to the system in the confinement of electrons by square well confinement potential. We use the projected Liouville equation method with Equilibrium Average Projection Scheme (EAPS). In order to analyze the quantum transition, we compare the temperature and the magnetic field dependencies of the QTLW and the QTLS on two transition processes, namely, the phonon emission transition process and the phonon absorption transition process. Through the analysis of this work, we found the increasing properties of QTLW and QTLS of Si with the temperature and the magnetic fields. We also found the dominant scattering processes are the phonon emission transition process.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.27-27
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• 2022

(-)-Epicatechin (EC), a primary form of flavan-3ol and a building block of proanthocyanidins, has health benefits as it is a potent antioxidant. So far, no quantitative trait loci (QTLs) associated with EC have yet been identified in soybean. In this study, QTLs for EC and hilum color were identified in recombinant inbred lines (RILs) derived from the varieties Jinpung and IT109098 using high-resolution single nucleotide polymorphism linkage mapping. This revealed two major QTLs for EC content, qEC06 and qEC08. qEC06 spanned the T Locus encoding flavonoid 3'-hydroxylase. qEC08, located near the I locus on Chr08, was also a major QTL for hilum color; however, allelic stacking of qEC08 and I revealed no relationship between I and EC content. RILs with IT 109098 alleles at both qEC06 and qEC08 had higher EC content than other lines. These results will enable the production of soybean varieties with high EC content via marker-assisted selection.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.539-545
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• 2004

The purpose of this study was to locate the quantitative trait loci (QTL) associated with quality properties in the recombinant inbred lines derived from the 'Milyang 23' and 'Gihobyeo' cross. Four quality-related traits; protein content, amylose content, fat acid content and sensory value were measured. Eight QTLs for protein content were detected on chromosomes 1 (two loci), 3, 6, 7 and 8 (three loci), each accounting for $6.0\%\~15.2\%$ of the phenotypic variation. Three QTLs for amylose content were detected on chromosomes 6 and 7 (two loci), each explaining from $7.3\%\;to\;24.4\%$ of the phenotypic variation. Six QTLs for fat acid content were detected on chromosomes 2 (two loci), 3, 6 (two loci) and 7, each explaining form $5.5\%\;to\;14.0\%$ of the phenotypic variation. Six QTLs for sensory value were detected on chromosomes 2, 6, 7(two loci) and 8 (two loci), each accounting for $5.5\%\~10.3\%$ of the phenotypic variation.

• Journal of Life Science
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• v.16 no.6
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• pp.949-954
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• 2006

Soybean [Glycine max (L.) Merr.] is an important crop, accounting for 48% of the world market in oil crops. Improvement of the quality and quantity of soybean seed constituents is one of the most important objectives in soybean breeding. Protein content and seed size are important properties to determine the quality of tofu and soy sprouts respectively. The objective of this study was to identify quantitative trait loci (QTLs) that control seed weight, protein and oil content in soybean. The 117 $F_{2:10}$ recombinant inbred lines (RlL) developed from a cross of 'Keunolkong' and 'Shinpaldalkong' were used. Narrow-sense heritability estimates based on a plot mean on seed weight, protein and oil content were 0.8, 0.78 and 0.71, respectively. Four independent QTLs for seed weight were identified from linkage group (LG) F, I and K. Five QTL for protein content were located on LG D1b, E, H, I and L. Oil content was related with six QTLs located on LG D1b, E, G, I, J and N. Protein and oil content have three common QTLs on LG D1b, E and I. Thus, we identified major loci improving soybean seed quality.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.712-721
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• 1997

The objectives of this study were; (1) to identify and localize QTLs for resistance to soybean cyst nematode(SCN) race 5 on RAPD map, (2) to idntify the magnitude and mode of inheritance for each QTL, and (3) to identify the best combinations of QTLs for resistance to SCN race 5. Based on the univariate regression analysis, we detected 26 markers(22 RAPD and 4 RFLP) which showed significant association(P<0.05) with resistance to SCN race 5. From MAPMAKER /QTL analysis, we identified two regions (LGC-20 and Group 2) for resistance to SCN race 5. The QTL that was localized at 8.0 cM from pK418C on LGC-20 showed a recessive mode of inheritance and the QTL that was localized between W03 and E02$^3$ on Group 2 showed a dominant mode of inheritance. Two pairs of flanking markers (E02$^3$ and W03, pK418C and pK418E$_1$) and one unlinked RAPD marker, G10$^1$ were used for multiple regression analysis. Marker combination which was composed of 4 markers, E02$^3$, G10$^1$, W03, and pK418E$_1$, explained the highest amount of phenotypic variation by SCN (35.2％). Further research for the identification of QTLs for resistance to SCN race 5 to explain larger portion of phenotypic variation is needed.