• Mycobiology
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• 제46권1호
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• pp.72-78
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• 2018

The fruiting body pattern is an important agronomic trait of the edible fungus Auricularia auricula-judae, and an important breeding target. There are two types of fruiting body pattern: the cluster type and the chrysanthemum type. We identified the fruiting body pattern of 26 test strains, and then constructed two different near-isogenic pools. Then, we developed sequence characterized amplified region (SCAR) molecular markers associated with the fruiting body pattern based on sequence-related amplified polymorphism (SRAP) markers. Ten different bands (189-522 bp) were amplified using 153 pairs of SRAP primers. The SCAR marker "SCL-18" consisted of a single 522-bp band amplified from the cluster-type strains, but not the chrysanthemum strains. This SCAR marker was closely associated with the cluster-type fruiting body trait of A. auricula-judae. These results lay the foundation for further research to locate and clone genes controlling the fruiting body pattern of A. auricula-judae.

• Animal Bioscience
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• 제34권8호
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• pp.1303-1308
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• 2021

Objective: The objective of this study was to define a new composite trait for Holstein dairy cows and evaluate the possibility of joint improvement in milk and fertility traits. Methods: A data set consisting 35,882 fertility related records (days open [DO], calving interval [CI], and number of services per conception [NSC], and total milk yield in each lactation [TMY]) was collected from 1998 to 2016 in Polish Holstein-Friesian breed herds. In this study TMY, DO, CI, and lactation length of each cow was used to obtain composite milk and fertility traits (CMF). Results: Moderate heritability (0.15) was estimated for composite trait that was higher than heritability of female fertility related traits: DO 0.047, CI 0.042, and NSC 0.014, and slightly lower than heritability of TMY 0.19. Favourable genetic correlations (-0.87) were estimated between CMF with TMY. Spearman rank correlation coefficients between breeding value of CMF with DO, CI, and TMY were high (>0.94) but with NSC were moderate (0.64). Selection on CMF caused favourable correlated genetic gains for DO, CI, and TMY. Different selection indices with different emphasis on fertility and milk production were constructed. The amount of correlated genetic gains obtained for DO and total milk production according to selection in CMF were higher than of genetic gains obtained for DO and TMY in selection indices with different emphasis on milk and fertility. Conclusion: The animal selection only based on a composite trait - CMF proposed in current study would simultaneously lead to favourable genetic gains for both milk and fertility related traits. In this situation CMF introduced in current study can be used to overcome to limitations of selection index and CMF could be useful for countries that have problems in recording traits, especially functional traits.

• Asian-Australasian Journal of Animal Sciences
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• 제14권4호
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• pp.587-596
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• 2001

In the last decade, rapid developments in molecular biotechnology and of genomic tools have enabled the creation of dense linkage maps across whole genomes of human, plant and animals. Successful development and implementation of interval mapping methodologies have allowed detection of the quantitative trait loci (QTL) responsible for economically important traits in experimental and commercial livestock populations. The candidate gene approach can be used in any general population with the availability of a large resource of candidate genes from the human or rodent genomes using comparative maps, and the validated candidate genes can be directly applied to commercial breeds. For the QTL detected from primary genome scans, two incipient fine mapping approaches are applied by generating new recombinants over several generations or utilizing historical recombinants with identity-by-descent (IBD) and linkage disequilibrium (LD) mapping. The high resolution definition of QTL position from fine mapping will allow the more efficient implementation of breeding programs such as marker-assisted selection (MAS) or marker-assisted introgression (MAI), and will provide a route toward cloning the QTL.

• 한국작물학회지
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• 제60권1호
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• pp.75-84
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• 2015

Sesame (Sesamum indicum L.) is one of the most important oilseed crops with high oil contents and rich nutrient value. The development of a core collection could facilitate easier access to sesame genetic resources for their use in crop improvement programs and simplify the genebank management. The present study was initiated to the development and evaluation of a core collection of sesame based on 5 qualitative and 10 quantitative trait descriptors on 2,751 sesame accessions. The accessions were different countries of origin. About 10.1 percent of accessions were selected by using the power core program to constitute a core collection consisting of 278 accessions. Mean comparisons using t-test, Nei's diversity index of 10 morphological descriptors and correlation coefficients among traits indicated that the existing genetic variation for these traits in the entire collection has been preserved in the core collection. The results from this study will provide effective information for future germplasm conservation and improvement programs in sesame.

• 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.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1525-1531
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• 2015

Using next-generation sequencing, we conducted a genome-wide scan of selective sweeps associated with selection toward genetic improvement in Thoroughbreds. We investigated potential phenotypic consequence of putative candidate loci by candidate gene association mapping for the finishing time in 240 Thoroughbred horses. We found a significant association with the trait for Ral GApase alpha 2 (RALGAP2) that regulates a variety of cellular processes of signal trafficking. Neighboring genes around RALGAP2 included insulinoma-associated 1 (INSM1), pallid (PLDN), and Ras and Rab interactor 2 (RIN2) genes have similar roles in signal trafficking, suggesting that a co-evolving gene cluster located on the chromosome 22 is under strong artificial selection in racehorses.

• Asian-Australasian Journal of Animal Sciences
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• 제23권4호
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• pp.417-424
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• 2010

The purpose of this study was to detect significant SNPs for carcass quality traits using DNA chips of high SNP density in Hanwoo populations. Carcass data of two hundred and eighty nine steers sired by 30 Korean proven sires were collected from two regions; the Hanwoo Improvement Center of National Agricultural Cooperative Federation in Seosan, Chungnam province and the commercial farms in Gyeongbuk province. The steers in Seosan were born between spring and fall of 2006 and those in Gyeonbuk between falls of 2004 and 2005. The former steers were slaughtered at approximately 24 months, while the latter steers were fed six months longer before slaughter. Among the 55,074 SNPs in the Illumina bovine 50K chip, a total of 32,756 available SNPs were selected for whole genome association study. After adjusting for the effects of sire, region and slaughter age, phenotypes were regressed on each SNP using a simple linear regression model. For the significance threshold, 0.1% point-wise p value from F distribution was used for each SNP test. Among the significant SNPs for a trait, the best set of SNP markers were selected using a stepwise regression procedure, and inclusion and exclusion of each SNP out of the model was determined at the p<0.001 level. A total of 118 SNPs were detected; 15, 20, 22, 28, 20, and 13 SNPs for final weight before slaughter, carcass weight, backfat thickness, weight index, longissimus dorsi muscle area, and marbling score, respectively. Among the significant SNPs, the best set of 44 SNPs was determined by stepwise regression procedures with 7, 9, 6, 9, 7, and 6 SNPs for the respective traits. Each set of SNPs per trait explained 20-40% of phenotypic variance. The number of detected SNPs per trait was not great in whole genome association tests, suggesting additional phenotype and genotype data are required to get more power to detect the trait-related SNPs with high accuracy for estimation of the SNP effect. These SNP markers could be applied to commercial Hanwoo populations via marker-assisted selection to verify the SNP effects and to improve genetic potentials in successive generations of the Hanwoo populations.

• The Plant Pathology Journal
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• 제38권6호
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• pp.572-582
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• 2022

Sheath blight disease caused by the necrotrophic, soilborne pathogen Rhizoctonia solani Kuhn, is the global threat to rice production. Lack of reliable stable resistance sources in rice germplasm pool for sheath blight has made resistance breeding a very difficult task. In the current study, 101 rice landraces were screened against R. solani under artificial epiphytotics and identified six moderately resistant landraces, Jigguvaratiga, Honasu, Jeer Sali, Jeeraga-2, BiliKagga, and Medini Sannabatta with relative lesion height (RLH) range of 21-30%. Landrace Jigguvaratiga with consistent and better level of resistance (21% RLH) than resistant check Tetep (RLH 28%) was used to develop mapping population. DNA markers associated with ShB resistance were identified in F₂ mapping population developed from Jigguvaratiga × BPT5204 (susceptible variety) using bulk segregant analysis. Among 56 parental polymorphic markers, RM5556, RM6208, and RM7 were polymorphic between the bulks. Single marker analysis indicated the significant association of ShB with RM5556 and RM6208 with phenotypic variance (R²) of 28.29 and 20.06%, respectively. Co-segregation analysis confirmed the strong association of RM5556 and RM6208 located on chromosome 8 for ShB trait. This is the first report on association of RM6208 marker for ShB resistance. In silico analysis revealed that RM6208 loci resides the stearoyl ACP desaturases protein, which is involved in defense mechanism against plant pathogens. RM5556 loci resides a protein, with unknown function. The putative candidate genes or quantitative trait locus harbouring at the marker interval of RM5556 and RM6208 can be further used to develop ShB resistant varieties using molecular breeding approaches.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2021년도 추계학술대회
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• pp.17-17
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• 2021

• Asian-Australasian Journal of Animal Sciences
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• 제26권1호
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• pp.19-29
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• 2013

Marbling (intramuscular fat) is an important trait that affects meat quality and is a casual factor determining the price of beef in the Korean beef market. It is a complex trait and has many biological pathways related to muscle and fat. There is a need to identify functional modules or genes related to marbling traits and investigate their relationships through a weighted gene co-expression network analysis based on the system level. Therefore, we investigated the co-expression relationships of genes related to the 'marbling score' trait and systemically analyzed the network topology in Hanwoo (Korean cattle). As a result, we determined 3 modules (gene groups) that showed statistically significant results for marbling score. In particular, one module (denoted as red) has a statistically significant result for marbling score (p = 0.008) and intramuscular fat (p = 0.02) and water capacity (p = 0.006). From functional enrichment and relationship analysis of the red module, the pathway hub genes (IL6, CHRNE, RB1, INHBA and NPPA) have a direct interaction relationship and share the biological functions related to fat or muscle, such as adipogenesis or muscle growth. This is the first gene network study with m.logissimus in Hanwoo to observe co-expression patterns in divergent marbling phenotypes. It may provide insights into the functional mechanisms of the marbling trait.