• Journal of the Korean Society of Tobacco Science
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• v.14 no.2
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• pp.126-132
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• 1992

This experiment was conducted to examine estimates of heterosis, degree of dominance, heritability and phenotypic and genotypic correlation for several mutant characters in flue-cured tobacco variety. Significant heterosis was noted, recording 2.73 and 6.16% for leaf width, -6.86 and -4.72 for leaf shape index, 19.8 and 23.4% for bacterial wilt disease index in Fl an4 F2 generation, respectively, and -1.44 for days to flower in F2 generation. And also leaf width was appeared partial dominance in Fl, and leaf shape index in Fl and F2, Leaf width in F2 was appeared overdominance. Estimated heritabilities in the broad sense ranged from 0.77 to 0.87 for plant and stalk height and days to flower, while those of leaf number, leaf length and width, leaf shape index and bacterial wilt disease index ranged from 0.50 to 0.65. And the heritabilities in the narrow sense were appeared 0.64 and 0.72 for stalk and plant height, respectively, and the others were ranged from 0.32 to 0.47 Positive genotpic correlations appeared among plant height, stalk height, leaf length and leaf width, and between leaf shape index ands day to flower. And negative genotypic correlations appeared between leaf shape index and plant height and stalk height and leaf width, and between bacterial wilt disease index and leaf length.

• Journal of Sericultural and Entomological Science
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• v.35 no.2
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• pp.100-104
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• 1993

The genetics analysis for weight of matured silkworm(WMS) and number of eggs produced per moth(NEM) was studied by the seven parents diallel. Mean squares of additive effect, dominant effect, maternal effect and reciprocal effect were significant for two characters observed. The component of genetic variance analysis for WMS and NEM showed that dominant effect was higher than additive effect. Narrow sense heritability(h2ns) estimates were 0.773 and 0.228, in the WMS and NEM. The estimate of broad sense heritability(h2bs) value was higher than that of h2ns because of the low importance of dominance effect. Incomplete dominance was shown by Vr-Wr graphic analysis in the weight of matured silkworm and overdominance in the number of eggs produced per moth. In general combining ability effect, Jam 107 and Jam 124 was showed positively high for WMS and Jam 107 and S1 was expressed positively high for NEM. In specific combining ability effect, hybrids in S1XC51, S1XJam124 and Jam 107XJam 108 were exhibited positively high for WMS and Jam 107XN63, S1XC51, N74XJam 108 and Jam 107XJam 108 were found positively high for NEM.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.77-83
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• 2014

To improve the breeding efficiency of oriental pear, the inheritance of major fruit traits were analyzed using 4,035 seedlings of 15 cross combinations combined with 13 cultivars. Yearly variation of parental cultivars, broad-sense heritability of the traits, and frequency of seedlings with commercially acceptable characteristics by the mid-parent values were studied. Despite the heritabilities of traits related with pear the fruit texture were different depending on cross combination, the average narrow-sense heritability ($h^2$) for firmness, flesh hardness, flesh density and grit were over 0.6, a relatively high value. However fruit firmness showed different heritability among the cross combination and its value of cross combination between 'Niitaka' and 'Choju' was very low as 0.11. Positive correlation was not observed on fresh hardness, fresh density and grit but observed on firmness between mid-parent value and average value of offspring. Regression of offspring on firmness, fresh hardness, fresh density and grit between mid-parent value and average value of offspring were 0.778, 0.343, -0.273, 0.313, respectively. Frequency distributions of fruit texture in 15 cross combinations of pear seedling was influenced by parental characteristics. When fruit firmness was estimated as low, low ${\times}$ high and high ${\times}$ high values in parental fruits, firmness in their offspring exhibited low, medium and high, respectively. In addition, when parental grit by sensory evaluation were light ${\times}$ light and light-medium ${\times}$ medium-heavy, most of offsprings showed light and medium grit, respectively.

• Journal of Life Science
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• v.12 no.2
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• pp.213-218
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• 2002

The experiment was conducted to get basic information for cotton breeding program through four-variety diallel cross population. Additive, dominant, maternal, and reciprocal effect were observed significantly for days to maturity. Based on the Vr-Wr graphical analysis, the characters, number of bolls per plant, boll weight, seed and lint weight per boll, lint weight per boll, width of seed, 100-seed weight, days to flowering, and days to maturity were found to inherit incomplete dominance, and the characters of number of bolls per plant, width of seed, number of seeds per boll, and length of seed were assumed to inherit over dominance. The component of genetic variance analysis for boll weight, seed and lint weight per boll, lint weight per boll, number of seeds per boll, length of seed, and days to flowering showed that additive effects were higher than dominant effects. The narrow-sense heritability(h$_2$N) for boll weight, seed and lint weight per boll, lint weight per boll, days to flowering, and days to maturity showed high values as more than 43.19%. The estimate of broad-sense heritability(h$_2$B) value was higher than that of h$_2$N because of the low importance of dominance effects.

• The Plant Pathology Journal
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• v.37 no.4
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• pp.315-328
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• 2021

Fusarium and Rhizoctonia genera are important pathogens of many field crops worldwide. They are constantly evolving and expanding their host range. Selecting resistant cultivars is an effective strategy to break their infection cycles. To this end, we screened a collection of Medicago truncatula accessions against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solani strains isolated from different plant species. Despite the small collection, a biodiversity in the disease response of M. truncatula accessions ranging from resistant phenotypes to highly susceptible ones was observed. A17 showed relative resistance to all fungal strains with the lowest disease incidence and ratings while TN1.11 was among the susceptible accessions. As an initiation of the characterization of resistance mechanisms, the antioxidant enzymes' activities, at the early stages of infections, were compared between these contrasting accessions. Our results showed an increment of the antioxidant activities within A17 plants in leaves and roots. We also analyzed the responses of a population of recombinant inbred lines derived from the crossing of A17 and TN1.11 to the infection with the same fungal strains. The broad-sense heritability of measured traits ranged from 0.87 to 0.95, from 0.72 to 0.96, and from 0.14 to 0.85 under control, F. oxysporum, and R. solani conditions, respectively. This high estimated heritability underlines the importance of further molecular analysis of the observed resistance to identify selection markers that could be incorporated into a breeding program and thus improving soil-borne pathogens resistance in crops.

• 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.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.442-448
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• 1985

The objective of this study was to compare year variations of heritability, phenotypic, genotypic and environmental correlations as well as pathway coefficients for main characters of tea tree to provide useful selection information for improving tea tree. The data collected from the performance yield trials from 1979 to 1981 were used in this study. 1. The genetic variance of height of stem and length of first branch was not only greatly varied with year. but also the largest among all characteristics studied. Other characteristics showed higher genetic variance than environmental variances, and year variances were very small. 2. Both year and variety x year interaction were highly significant sources of variation for height of stem, length of first branch and number of fruits in main stem pooled from three year data. 3. All characteristics showed high broad sense heritabilities, and the broad sense heritability was not varied with year. 4. The genetic correlation coefficients between Gigolpi and height of stem, length of first branch and number of fruits in main stem were positive, and the year variation was not large. 5. The pathway coefficients of the character was not only greatly varied with year and the height of stem, length of first branch and weight of dryed root affected directly on the Giglopi.

• Korean Journal of Plant Resources
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• v.20 no.2
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• pp.168-176
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• 2007

Heterosis, combining ability, genetic components, effective factor no. and heritability for yield of seed cotton per plant, boll no., seeds per boll, seed length, seed width and lint weight per boll were investigated in $5{\times}5$ half diallel set of crosses involving diverse upland cultivars. Both heterosis and heterobeltiosis for yield per plant, boll number, seed length and lint weight showed significantly negative values. Both general combining ability (GCA) and specific combining ability (SCA) showed highly significant. Overdominance was observed for yield per plant, boll number, seeds per boll and seed width, complete dominance for seed length and partial dominance for lint weight. The number of effective factor was estimated as two for yield per plant, boll number and seed length and estimated as one for seeds per boll, seed width and lint weight. Narrow sense heritability was low for yield per plant, boll number and seeds per boll. Broad sense heritability was very high for all the characters excepting lint weight.

• Current Research on Agriculture and Life Sciences
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• v.20
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• pp.1-8
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• 2002

This study was conducted to obtain the information of varietal development using wild soybean through investigation of variation and heredity of major agronomic characters in $F_2$ generation of interspecific cross between Glycine max and G. soja. In segregating populations of two crosses, all characters observed except 100-seed weight showed transgressive segregation. Days to flowering showed normal distribution; mean days to flowering in $F_1$, and $F_2$ was approximately mean of parent. Mean of $F_1$ for 100-seed weight was 6.2g and 5.7g for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which were somewhat skewed distribution to small seeded parents. Mean seed yield of $F_2$ was about mean of two parents. Degree of vine was 6.4 and 5.7 in $F_1$ for two crosses but it was 6.0 in $F_2$ for Eonbakong/KLG10084, which revealed the degree of vine as partial dominance while 4.6 for Sobaegnamulkong/KLG10084, somewhat different results from the previous cross. Broad-sense heritability($h^2B$) for plant height, days to flowering, pods per plant, seed yield, and degree of vine was comparatively high and narrow-sense heritability($h^2B$) for 100-seed weight which is the moot important character in the development of small seed-size sprout soybean was 52.3% and 65.6% for Eunhakong/KLG10084 and Sohaegnamulkong/KLG10084, respectively, which indicated that selection for the character in early generation was possible.

• Journal of Korean Society of Forest Science
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• v.69 no.1
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• pp.1-5
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• 1985

Growth characters such as height, DBH, crown width, branch length and branch diameter were measured from 23 clones of plus trees of Pinus koraiensis. The results were as follows; 1) Differences between the largest and smallest clones were amounted to 41% in height, 81% in DBH, 50% in crown width, 55% in branch length and 83% in branch diameter. 2) There were significant differences between clones in every growth characters and correlation coefficients between growth characters were positive and significant ($r=0.418^*{\sim}0.917^{**}$). 3) The broad sense heritabilities were 0.46 for height, 0.45 for DBH, 0.28 for crown width, 0.26 for branch length and 0.18 for branch diameter. 4) The genetic gains predicted for each characters were ranged from 4.1% to 11.1%, when selecting the best 3 out of 23 clones.