• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1109-1115
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• 2008

The reproduction component traits are important components of sow efficiency. The objective of this study was to evaluate the phenotypic and genetic parameters of four reproduction component traits (age at puberty (AP), preweaning number dead (PND), weaning to service interval (WSI), and intra-individual SD in litter size (IISDLS)) of sows in two Chinese indigenous pig breeds. Available reproductive records including 22,591 piglets born from 2,054 litters by 574 Jiangquhai sows and 464 Meishan sows were used in this investigation. A set of mixed models and restricted maximum likelihood methodology were used for the multiple trait analyses of these traits. The results showed that the estimates of heritabilities (${\pm}$standard error) for AP, PND, WSI and IISDLS were $0.40{\pm}0.05$, $0.06{\pm}0.03$, $0.20{\pm}0.02$ and 0.09{\pm}0.03 in Jiangquhai sows, and $0.35{\pm}0.06$, $0.05{\pm}0.03$, $0.18{\pm}0.03$ and $0.10{\pm}0.04$ in Meishan sows, respectively. There was moderate genetic correlation between AP and WSI, while there were low genetic correlations between the other pairwise traits. The genetic correlations were positive for most of the pairwise traits, except for the one between AP and IISDLS. The results indicated that all traits except for AP were difficult to make genetic improvement by traditional selection methods due to low heritabilities and the favorable improvement of AP might result in unfavorable changes of IISDLS due to the trend of genetic antagonism.

• Korean Journal of Poultry Science
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• v.16 no.1
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• pp.9-15
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• 1989

This study was conducted to estimate genetic parameters for egg yolk cholesterol. Content of egg yok cholesterol was measured for a total of 473 hens of White Leghorn line. Cholesterol values were obtained from tee consecutively laid eggs when hens were 53 weeks of age. The yolk of each egg was weighted and freeze dried. Dried egg yolks were stored at -2$0^{\circ}C$ until analyzed. The results obtained from this study were as follows; 1. Yolk cholesterol content was measured in average $56.00\pm$0.194 mg/g dry yolk. 2. Heritability from the sire component of variance was $0.522\pm$0.215 and from the sire＋dam component of variance $0.33\pm$0.209. 3. Estimates of phenotypic correlation between your cholesterol and other factors such as body weight at 20 weeks of age, age at first egg, 40-week total egg number, egg Production rate: 53-week egg weight and 53-week yolk weight were -0.0208, -0.0321, -0.0378, -0.0834, 0.0790 and 0.1624, respectively. And genetic correlation coefficients for each item in the order were -0.5293, 0.7105, -0.4062, -0.0254, 0.2164 and 0.5027, respectively. 4. These results suggest the possibility that egg Yolk cholesterol should be reduced through selecting of sire families. To breed for low egg yolk cholesterol, it makes age at first egg earlier and enhances total egg number so that we can obtain the high rate of egg Production.

• Journal of Animal Science and Technology
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• v.49 no.2
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• pp.177-182
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• 2007

The objective of this study was to evaluate the genetic relationship between weaning weight (WW) and carcass traits. Carcass traits were eye muscle area(EMA), back fat thickness(BFT), marbling score 1(MS1) in 21 grade scales, marbling score 2(MS2) in 7 grade scales and meat color scores(Mcolor). Parameters were estimated by REML procedure with MTDFREML package. Models included contemporary group as defined by the same year-season-sex at birth, linear covariates of age(days) at weaning, age of dam(days) and age at slaughter(days) as fixed effects and animal random effects for all the traits. Heritability estimates of WW, EMA, BFT, MS1, MS2 and Mcolor were 0.25, 0.20, 0.20, 0.32, 0.32 and 0.22, respectively. Genetic(phenotypic) correlation coefficients of WW with EMA, BFT, MS1, MS2 and Mcolor were 0.75(0.16), 0.18(0.05), －0.41(－0.09), －0.40(0.11) and －0.07(0.05), respectively. Results from this study suggest that single trait selection for weaning weight would lead to progeny population having carcass with large EMA, thick BFT and decreased MS.

• Korean Journal of Poultry Science
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• v.13 no.2
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• pp.173-178
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• 1986

Data on egg production, egg weight and egg mass were obtained from a sample of the Synthetic White Leghorn population which was raised at Poultry Breeding Farm, Seoul National University. Egg mass was not measured directly, but was calculated from the egg numbers and the average egg weight for same period. Phenotypic means, components of variance and covariance, heritabilities and genetic correlations were computed. Egg mass was estimated to be a lowly heritable trait (0.204-0.270). High heritability estimates were found for age at sexual maturity and egg weight. Genetic correlation estimates were high and positive between egg mass and egg number(combined estimates 0.711). Egg mass and egg weight were moderately correlated genetically (0.431). Genetic correlation estimates was -0.280 between egg number and age at sexual maturity, but was 0.524 between egg weight and age at sexual maturity. Results show that selection for total egg mass based on record from a single period will not be satisfactory unless the single period chosen is one in the latter part of the laying year.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.31-37
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• 1986

Seven cultivars of hard and soft wheat were evaluated by regression analysis for five bread quality characteristics to determine varietal response to environments. The regression coefficients were used as the measure of adaptability, and determination coefficients were used as the measure of stability by models of Eberhart and Russell. Phenotypic, genotypic and environmental correlation coefficient estimated for 6 characters tested in this experiments. Statistical analyses confirmed the strong influence of environment on five bread quality. A significant positive correlation exists between protein content, sedimentation value, pelshenke value and specific loaf volume. High heritability was found for sedimentation value ($h^2=0.747$), protein content ($h^2=0.557$) and specific loaf volume ($h^2=0.551$).

• Horticultural Science & Technology
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• v.33 no.5
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• pp.737-750
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• 2015

This study was carried out to construct a DNA profile database for 102 watermelon cultivars through the comparison of polymorphism level and genetic relatedness using genomic microsatellite (gMS) and expressed sequence tag (EST)-microsatellite (eMS) markers. Sixteen gMS and 10 eMS primers showed hyper-variability and were able to represent the genetic variation within 102 watermelon cultivars. With gMS markers, an average of 3.63 alleles per marker were detected with a polymorphism information content (PIC) value of 0.479, whereas with eMS markers, the average number of alleles per marker was 2.50 and the PIC value was 0.425, indicating that eMS detects a lower polymorphism level compared to gMS. Cluster analysis and Jaccard's genetic distance coefficients using the unweighted pair group method with arithmetic average (UPGMA) based on the gMS, eMS, and combined data sets showed that 102 commercial watermelon cultivars could be categorized into 6 to 8 major groups corresponding to phenotypic traits. Moreover, this method was sufficient to identify 78 out of 102 cultivars. Correlation analysis with Mantel tests for those clusters using 3 data sets showed high correlation ($r{\geq}0.80$). Therefore, the microsatellite markers used in this study may serve as a useful tool for germplasm evaluation, genetic purity assessment, and fingerprinting of watermelon cultivars.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.474-481
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• 2009

The purpose of this study was to identify the quantitative trait loci (QTL) associated with gel consistency (GC), and to evaluate the relationships between GC and physico-chemical properties related to eating quality in rice. A total of 120 doubled haploid (DH) lines derived from a cross between 'Samgang' and 'Nagdong' and 26 varieties were used for this study. The 120 DH lines were divided into four groups, soft (61~100 mm), medium (41~60 mm), hard (26~40 mm) and whole population, according to the gel length. A negative correlation between GC and amylose content was observed only in the soft group. The GC negatively correlated with lipid content in the medium, and the whole population, but positively correlated with lipid content in the soft group. The positive correlation between GC and protein content was observed in the soft group, while negative correlations were observed in the medium group and the whole population. Two significant QTLs regarding GC were detected on chromosomes 4 and 11. They collectively explained 23% of phenotypic variation with LOD score of 3.1 and 2.9, respectively. The DNA markers of S4026 and RM287 were tightly linked to GC in the DH population and 26 varieties, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.2
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• pp.281-313
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• 1976

To obtain fundamental informations on cotton breeding efficiences for Korea, individual genetic relationships and interrelationships between the agronomic characteristics of Upland cotton were investigated. These experiments were couducted at the Mokpo Branch Station $(34^{\circ}48'N, $ $126^{\circ}23'E$ and altitude of 10m above sea level) from 1969 through 1972. Heterosis, combining ability, dominance and recessive gene action, genetic variance, and phenotypic and genotypic correlation were investigated by $F_1'S$ from an 11-parent partial diallel cross and the segregating $F_2$ and $F_3$ populations of the cross Paymaster times Heujueusseo Trice. The following points resulted from this study, 1. Heteroses for number of bolls per plant and lint yield were significant at 27, 84% and 37.26%, respectively. No other character had significant heteroses. 2. The GCA estimates for all studied characteristics were higher than the SCA estimates. Varieties with high GCA effects were Suwon 1 for earliness, Paymaster and Arijona for high lint percent, and Arijona for long fiber, etc, 3. SCA estimates for lint yield varied widely in crosses with Mokpo 4, Mokpo 6 and Heujueusseo Trice. Those crosses with the highest SCA effects were combinations with large characteristics differences, Example of these crosses are Mokpo 4 times Acala 1517W, Mokpo 4 times D. P. L. and Heujueusseo Trice aud Paymaster. 4. Early-maturing varieties were completely dominant to late-maturing varieties in some combinations while other crosses gave intermediate phenotypes. These results suggest additive genetic action by multi-genes. Heujueusseo Trice, Mokpo 6, and Suwon 1 showed highest degree of dominance for earliness. 5. There were no significant trends for inheritance of weight of boll and 100 seeds weight. 6. Long staple was partially to completely dominant to short staple. Though there were single gene ratios the rate of dominance decreased in the $F_2$ and $F_3$ populations in the cross between the long staple variety Paymaster and the short staple variety Heujueusseo Trice. Diallel cross $F_1$ hybrids showed complicated allelic gene action for staple length. Various dominance degree were shown by varieties. 7. Number of bolls per plant indicated strong over-dominance and small non-allelic additive gene action. 8. Lint Yield was characterized by over-dominance and by multiple non-allelic-gene action. High-yielding varieties were dominant to low-yielding ones. However, the low-yielding variety Heujueusseo Trice showed over-dominance, indicating different reactions according to the varieties and combinations. 9. Broad sense heritability for days to flowering was 34-39% while narrow sense heritability was 11%. Large variations of individual plants caused by Korean climatic conditions cause this situation. Heritability estimates for weight of boll was 30% for broad sense and 22% for narrow sense. 10. Heritability estimates for staple length and lint percent were very high suggesting strong selection effects. 11. Narrow sense heritability estimates for number of bolls per plant was 30% in the diallel cross $F_1$ hybrids and 36% in the $F_2$ population of the special cross. Broad sense heritability was estimated at 67% suggesting that. 12. Heritability estimates for lint yield was low due to high over-dominance in the diallel cross $F_1$ hybrids. Heritability estimates for yield was low in the $F_1$ hybrids but high in the $F_2$ and $F_3$ populations. 13. Phenotypic and genotypic correlations between lint percent and days to flowering and between staple length and days to flowering were high in the $F_1, $ $F_2$ and $F_3$ populations. Late-maturing varieties and individuals had long staple and high lint percent in general. As the correlation between days to flowering and lint yield was extremely low, the two traits were considered independent of each other. Days to flowering and number of bolls per plant were negatively correlated in the $F_3$ population, indicating early-maturing individual plants with many bolls may be readily selected. 14. Phenotypic and genotypic correlations between lint percent and staple length were high in $F_1, $ $F_2$ and $F_3$ populations. Accordingly, long staple varieties were high in lint percent. It was recognized that lint yield and lint percent were positively correlated in the diallel cross $F_1$ hybrids, and lint percent and staple length were positively correlated in the $F_2$ population, indicating that lint percent and staple length affect lint yield. 15. Lint yield was significantly and positively phenotypically correlated with number of bolls per plant in $F_1, $ $F_2$ and $F_3$ populations. A high genotypic correlation was also noted indicating a close genetic relationship. The selection efficiencies for a high-yielding variety can be increased when individual plants with many bolls are selected in later generations. The selection efficiencies for good fiber quality can be enhanced when individuals with long staple and high lint percent are selected in early generations.

• Journal of Korean Society of Forest Science
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• v.79 no.1
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• pp.56-70
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• 1990

Eighteen Korean white pine (P. koraiensis S. et Z.) families were tested in 3 different regions from age 5 to 9. Family and site were significant sources of variation for seedling survival and field growth, whereas the effects of family x site interaction ware relatively small as compared with the former sources of variation. Variance components estimated from the separate and combined sites indicated that the most variabilities were associated with individual trees within plot. Family ${\times}$ site interaction components as a percentage of family variance decreased sharply with age. Heritability estimates varied with testing site and tree age. Combined analyses, however, showed a moderate change in heritability with increasing tree ages, and demonstrated high and stable trends of estimates, particularly in family heritabilities of tree height ($h_F{^2}=0.789-0.798$). The gains estimated from combined analysis have expected maximum or near-maximum efficiencies at age 6 or 7. Given equal intensity of selection, mass selection showed the most efficient gains within and across the sites. However, for the differences between mass and combined selections are small, selection made on the combination of family and within-family would be more effective in improving genetic gains. Indirect selection method indicated that 5-and 6-years height were all good predictors of 9-year-old height with little loss of relative efficiency (less than 10%) as compared with direct family selection at age 9. Phenotypic and genetic correlations computed on the basis of family mean values of height and diameter have shown predominantly high, positive, and statistically significant (1% level) relationships between all tested pairs of traits, which indicates that family growth maintained statistically consistent trends with age. The best families are those that maintained a stable superiority overall sites and ages in growth performance, therefore, it can be suggested that early identification of superior families at age 9 is feasible at age 5 or 6 in Pinus koraiensis S. et Z.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.369-380
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• 2023

Developing and breeding improved legume-based food resources require collecting useful genetic traits with heritability even though requiring some time-consuming, costly, and labor intensive. We attempted to infer heritability of nine genetic traits-days to flowering, days to maturity, period from flowering to maturity, the number of seeds per pod, 100-seeds weight, and four contents such as crude protein, crude oil, crude fiber, and dietary fiber-using 455 homologous chloroplast gene sets of six species of legumes. Correlation analysis between genetic trait differences and phylogenetic distance of homologous gene sets revealed that days to flowering, the number of seeds per pod, and crude oil content were influenced by genetic factors rather than environmental factors by 62.86%, 69.45%, 57.14% of correlated genes (P-value ≤ 0.05) and days to maturity showed intermediate genetic effects by 62.42% (P-value ≤ 0.1). The period from flowering to maturity and 100-seeds weight showed different results compared to those of some previous studies, which may be attributed to highly complicated internal (epistatic or additive gene effects) and external effects (cultural environment and human behaviors). Despite being slightly unexpected, our results and method can widely contribute to analyze heritability by including genetic information on mitochondria, nuclear genome, and single nucleotide polymorphisms.