• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.73-81
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• 1989

This study was conducted to estimate heritabilities, genetic and phenotypic correlations on economic traits in layers. The data analysis were the records of 351 pullets in S. C. W. Leghorn and 326 pullets in R. I. Red from March 1, 1980 to July 31.1981. The results obtained are summarized as follows：1 The average body weights at the first egg, 300 and 500 days of age were 1, 409, 1, 602 and 1, 709g S. C. W. Leghorn, and 1, 965, 2, 305, and 2, 479g in the R. I. Red, respectively. The age at first egg of the S. C. W, Leghorn and R. I. Red were 156 days and 163 days, respectively. The number of egg produced by the S. C. W. Leghorn and R. I. Red to 300 days and 500 days of age were 101.18, 214.39, and 101.05, 214.93, respectively. The egg weight at first egg, 300 and 500 days of age were 41.93, 57.65 and 60.33g in the S. C. W. Leghorn and 41.52, 57.62 and 60.57g in the R. I. Red, respectively. 2. The heritability estimates based on the variance of sire and dam components were 0.402-0.612 and 0.275-0.458 in the S. C. W. Leghorn, 0.309-0.523 and 0.134-0.380 in R. I. Red for body weight； 0.167 and 0.139 in the 5. C. W. Leghorn, 0.169 and 0.095 in the R.1. Red for age at first egg：0.214-0.139 and 0.336-0.341 in S. C. W Leghorn, 0.137-0.259 and 0.024-0.102 in the R. I. Red for number of egg production； 0.537-0.769 and 0.374-0.686 in the S. C. W. Leghorn, 0.519-0.631 and 0.116-0.365 in the R. I. Red for egg weight, respectively. 3. The genetic correlation coefficients of economic traits were as follows： In the S. C. W. Leghorn and R. I. Red , the coefficients between body weights and age at the first egg, 0.328-0.426 and 0.186-0.244：between body weights and number of egg production, -0.666--0.498 and -0.452--0.073：between body weight and egg weight, 0.384-0.774 and 0.126-0.612； between age at first egg and number of egg production, -0.639--0.452 and -0.754--0.320； between age at first egg and egg weight, 0.475-0.705 and 0.021-0.605； between number of egg production and egg weight, -0.623--0.355 and -0.861--0.327, respectively.

• Korean Journal of Breeding Science
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• v.41 no.3
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• pp.228-235
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• 2009

Growth and branch characteristics of 35 half-sib families were surveyed in a seedling seed orchard of Quercus acutissima at ages 10 and 12. The averages of height, DBH (diameter at breast height), branch height, crown width, branch angle and stem straightness at age 12 were 9.96 m, 14.50 cm, 1.04 m, 6.80 m, $18.82^{\circ}$ and 2.58, respectively. Families of 075 and 052 showed superior height growth and 0511 and 0517 were inferior ones. For DBH growth, 075 and 0413 were best families and 0725 and 0511 were inferior families. Pearson's product moment and Spearman's rank correlation coefficients were all positive for all growth traits except branch angle at ages 10 and 12. This result showed that the families with good height and DBH growth were also superior in stem straightness. In ANOVA, there was a highly significant difference among families in height, DBH, cylindric volume and stem straightness. Branch height, crown width and branch angle were also significantly different among families. Family heritability was higher than individual heritability at ages 10 and 12. Height, DBH and stem straightness were under strong genetic control, showing high family heritability. This implies that high genetic gain could be expected by family selection. Expected genetic gain for each trait was estimated based on the family selection. The highest genetic gain was expected for the traits of branch angle, height and DBH because of the large phenotypic standard deviation and the high family heritability. The growth performance and branch characteristics were weighted by the magnitude of genetic variation and heritability. The weighted values were then subjected to estimate family breeding values. This family breeding value would be applied as a criterion in the genetic thinning of the seed orchard.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.641-651
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• 2022

The biodiversity research of barley, a functional food, is proceeding to conserve germplasms and develop new cultivar of barley to improve its functional effects. In this study, with 25,104 barley germplasms in the National Agrobiodiversity Center, South Korea, the biodiversity index of species was much lower (1.17) than the origins (24.73) because of the presence of a biased species, Hordeum vulgare subsp. vulgare, but the species and origin of germplasms were significantly different with regard to genetic traits. In the clustering analysis based on genetic traits, we found that 97% barley germplasms could mostly be distributed between 1~7 clusters out of a total of 15 clusters; 'normal and uzu type', 'lodging', and 'loose smut' were commonly represented in the 1~7 clusters and some clusters showed specific differences in five genetic traits including 'growth habit'. In correlation of each genetic trait, the infection of 'barley yellow mosaic virus' was highly correlated to 'number of grains per spike'. '1000 grain weight' was weakly correlated with seven genetic traits including 'number of grains per spike'. Our analysis for barley's biodiversity can provide a useful guide to the species' phenotypes that need to be collected to conserve biodiversity and to breed new barley varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.1
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• pp.1-8
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• 1992

This study was conducted to obtain the basic information on salt-tolerance of rice cultivars in relations with growth retardation and cation content. As the salt-level increased, less retardation in plant height and dry weight were shown in salt-tolerant than salt-susceptible rice cultivars. Salt tolerant cultivars showed lower N $a^{+}$ and higher $K^{+}$ content and lower N $a^{+}$ / $K^{+}$ ratio at each salt-levels than salt-susceptible ones, while there were no significant differences in $Ca^{++}$ and $Mg^{++}$ content. At the tillering stage, the plant height and dry weight of the salt-treated plots were significantly correlated with N $a^{+}$ and $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio, implying that N $a^{+}$ and $K^{+}$ content could be an indicator of salt-tolerance of a rice cultivar. There were no tiller-depending differences in cation content in all cultivars. N $a^{+}$ content and N $a^{+}$ / $K^{+}$ ratio in leaves were lower at the top and higher at the bottom. In three $F_1$ hybrids between salt tolerant parent Pokkali and three salt susceptible parents, plant height, dry weight, $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio were similar to those of Pokkali parent, while N $a^{+}$ content was intermediate of the parents. So, it seemed that salt tolerance is dominant over salt susceptibility. In $F_2$ of Pokkali/wx817 cross, genetic segregation of plant height, dry weight, $K^{+}$ content and N $a^{+}$ / $K^{+}$ ratio varied continuously and was biased onto Pokkali side, while that of N $a^{+}$ content showed normal distribution with intermediate mode. Broad-sense heritability of the characters ranged from 0. 604 to 0. 811. Genotypic and phenotypic correlation coefficients among them were relatively high.fficients among them were relatively high.h.h.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.3
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• pp.89-98
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• 1965

The experimental studies were intended to clarify the effects of selection, and also aimed at estimating the heritabilities, the genotypic correlations among some agronomic characters, and at calculating the selection index on some selective characters for the selection of desirable lines, under different climatic conditions. Finally practical implications of these studies, especially on the selection index, were discussed. Twenty-two varieties, determinate growing habit type, were selected at random from the 138 soybean varieties cultivated the year before, were grown in a randomized block design with three replicates at Chinju, Korea, under May and June sowing conditions. The method of estimating heritabilities for the eleven agronomic characters-flowering date, maturity date, stem length, branch numbers per plant, stem diameter, plant weight, pod numbers per plant, grain numbers per plant and 100 grain weight, shown in Table 3, was the variance components procedures in a replicated trial for the varieties. The analysis of covariance was used to obtain the genotypic correlations and phenotypic correlations among the eight characters, and the selection indexes for some agronomic characters were calculated by Robinson's method. The results are summarized as follows: Heritabilities : The experiment on the genotype-environment interaction revealed that in almost all of the characters investigated the interaction was too large to be neglected and materially affected the estimates of various genotypic parameters. The variation in heritability due to the change of environments was larger in the characters of low heritability than in those of high heritability. Heritability values of flowering date, fruiting period (days from flowering to maturity), stem length and 100 grain weight were the highest in both environments, those of yield(grain weight) and other characters were showed the lower values(Table 3). These heritability values showed a decreasing trend with the delayed sowing in the experiments. Further, all calculated heritability values were higher than anticipated. This was expected since these values, which were the broad sense heritability, contain the variance due to dominance and epistasisf in addition to the additive genetic variance. Genotypic correlations : Genotypic correlations were slightly higher than the corresponding phenotypic correlations in both environments, but the variation in values due to the change of environment appeared between grain weight and some other characters, especially an increase between grain weight and flowering date, and the total growing period(Table 6). Genotypic correlations between grain weight and other characters indicated that high seed yield was genetically correlated with late flowering, late maturity, and the other five characters namely branch numbers per plant, stem diameter, plant weight, pod numbers per plant and grain numbers per plant, but not with 100 grain weight of soybeans. Pod numbers and grain numbers per plant were more closely correlated with seed yields than with other characters. Selection index : For the comparison and the use of selection indexes in the selection, two kinds of selection indexes were calculated, the former was called selection index A and the later selection index B as shown in Table 7. Selection index A was calculated by the values of grain weight per plant as the character of yield(character Y), but the other, selection index B, was calculated by the values of pod numbers per plant, instead of grain weight per plant, as the character of yield'(character Y'). These results suggest that selection index technique is useful in soybean breeding. In reality, however, as the selection index varies with population and environment, it must be calculated in each population to which selection is applied and in each environment in which the population is located. In spite of the expected usefulness of selection index technique in soybean breeding, unsolved problems such as the expense, time and labor involved in calculating the selection index remain. For these reasons and from these experimental studies, it was recognized that in the breeding of self-fertilized soybean plants the selection for yield should be based on a more simple selection index such as selection index B of these experiments rather than on the complex selection index such as selection index A. Furthermore, it was realized that the selection index for the selection should be calculated on the basis of the data of some 3-4 agronomic characters-maturity date(X$_1$), branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant etc. It must be noted that it should be successful in selection to select for maturity date(X$_1$) which has high heritability, and the selection index should be calculated easily on the basis of the data of branch numbers per plant(X$_2$), stem diameter(X$_3$) and pod numbers per plant, directly after the harvest before drying and threshing. These characters should be very useful agronomic characters in the selection of Korean soybeans, determinate growing habit type, as they could be measured or counted easily thus saving time and expense in the duration from harvest to drying and threshing, and are affected more in soybean yields than the other agronomic characters.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.1-16
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• 1986

This experiment was carried out to obtain genetic information for future corn breeding. The materials used for the study were obtained from the nationwide collection of Korean local corn lines. A total of 262 lines were used for the study of morphological characters and for the classification of lines. Results obtained are summarized as follows; 1. The days to flowering of lines ranged from 57 days to 87 days. Most lines had an average of 67 days of flowering days. 2. The number of tillers of lines showed a lot of variation among lines with 49.2% of coefficient of variation. 3. The coefficients of variation computed based on the phenotypic observation or measurement of each line were 36.1%, 27.2%, 20.0%, 16.4% and 16.3% for kernel weight per ear, 100 kernel weight, ear height, plant height and ear length, respectively. 4. Ear height, ear length, ear diameter, tiller number and days to flowering were highly and positively correlation with the plant height. Kernel size, ear size, and plant height were highly correlated with 100 kernel weight and kernel weight per ear. 5. The 262 corn lines were possibly classified into four major groups by the Euclidean distance. Group I comprised 110 lines, group II 74 lines, group III 66 lines and group IV 12 lines, respectively. Group I was characterized as having early maturity, medium plant height large kernel size and large ear size. Group II had medium maturity, short plant height, medium kernel size and small ear size. Group III had medium maturity, medium plant height, large kernel size and medium ear size. Group IV had late maturity, long plant height, small kernel size, small ear size and many tillering. 6. The plant height showed significant difference between group I and II, II and III, and II and IV group. No statistical differences were observed between group III and IV. The ear size of group I was significantly different from those of group II, III and IV. Also difference of ear size between group II and III was significant. The kernel size, 100 kernel weight and kernel weight per ear were all significantly different among all groups classified. The row number was different between group I and II. The row number of lines in group IV was significantly different with group I, II, III respectively. The number of tillers and flowering days of lines in group IV were greatly different from those of group I, II and III. 7. The corn lines collected from northwest plain regions and middle hilly regions in Korea had medium maturity, medium plant height, large ear and large kernels. The corn lines from middle eastern hilly regions had medium size of ear kernels. The corn lines from middle southern hilly regions had late maturity, small kernel size and many tillers. The corn lines from southwest plain areas had late maturity, long plant height and many tillers.

• Korean Journal of Poultry Science
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• v.16 no.2
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• pp.83-89
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• 1989

This study was conducted to estimate heritabilities, genetic and phenotypic correlations on egg compositions in layers. The data analysis were a total of 6,097 eggs in S. C. W. Leghorn and R. I. Red from March 1, 1980 to July 31, 1981. The results obtained are summarized as follows； 1. The average albumen weight at first egg, 300 and 500 days of age were 28.67, 36.25 and 37.51g in the S. C. W. Leghorn, and 28.95, 36.01 and 36.85g in the R. I. Red, respectively. The yolk weigh at first egg ,300 and 500 days were 9.21, 15.94 and17.86g in the S. C. W. Leghorn,9.46, 16.43 and 18.54g in the R. I. Red, respectively. The shell weight at first egg, 300 and 500 days were 4.04, 5.39 and 5.40g in the S. C. W. Leghorn, and 3.66, 5.13 and 5.28g, respectively. 2. The heritability estimates based on the variance of sire and dam components were 0.631-0.164 and 0.412-0.496 in the S. C. W. Leghorn,0.234-0.563 and 0.477-0.610 in the R. I. Red for albumen weight； 0.213-0.530 and 0.343-0.613 in the S. C. W. Leghorn, 0.253-0.437 and 0.389-0.477 in the R. I. Red for yolk weight； 0.427-0.602 and 0.336-0.409 in the S. C. W. Leghorn, 0.141-0.281 in the R. I. Red for shell weight, respectively. 3. The genetic correlation coefficients of egg compositions were as follows； In the S. C. W. Leghorn and R. I. Red, the coefficients between albumen weight and yolk weight, 0.082-0.339 and 0.142-0.465； between albumen weight and shell weight, 0.674-0.952 and 0.216-0.546； between yolk weight and shell weight,0.173-0.171 and 0.121-0.749, respectively.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.1
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• pp.56-68
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• 1981

A maize line was selected in 1979 among 1000 Korean local maize lines collected in 1977. The selected maize line was characterized by having three to four tillers and eight to 10 ears on each individual plant. The line was assumed to have a great potential as a silage crop. The investigation was conducted as one of the serial studies on the Korean maize collected lines to provide basic information on the genetic variabilities of the multi-eared and tillered (MET) line and on other agronomic characters, prior to use the line as material for future breeding works for silage crop. The MET line and Suwon #19, single cross hybrid, as check variety were planted on May 1, 15 and 30, in three different levels of plant populations. The results obtained were summarized as follows: 1. The genetic variabilities of multi-ear and tillering habits were greater than environmental variabilities. 2. Total dry leaf weight of individual plant of MET line was also significantly higher than that of Suwon #19. 3. The mean number of tillers and ears bearing on the individual plant of MET line varied greatly with plant densities. The number of tillers and ears was on the average 2.9 and 7.0, respectively, when planted in 60cm. by 60cm. 4. The total dry matter and dried stem weight of the individual plant on MET line were comparable to those of Suwon #19. 5. The kernel weight from the individual plant of MET line was 5 to 40% less than that of Suwon #19, depending upon the plant densities. 6. The Kernel to stover ratio was higher for Suwon #19 than for the MET line. (41% to 35%). 7. The MET line had shown first tiller two weeks after planted on May 1. The second and third tillers appeared three to five days after the appearance of the first tiller. 8. The MET line was very specific in tillering habits. All the tillers were borne on the first few nodes of main stem below the soil surface. 9. The tillering habits of MET line were vigorous in the early part of the growing season, but less vigorous in the later part of the growing season. The number of efficient tillers bearing useable ears, was around two to three, when planted in 60cm. by 60cm. 10. The difference of plant height between main stem and first few tillers was around 10cm. 11. The ear size of MET line was around one-third of the major corn belt hybrids. The shape of ear of MET line was conical, with different diameter. 12. The kernel of the MET line was flinty with small soft starch patches on the endosperm part. 13. The 100 kernel weight was around 15gr., which is about one half of the major high yielding hybrids. 14. The ear height of MET line was comparatively higher than that of Suwon #19. 15. Significantly high and positive phenotypic correlation coefficients were obtained among major plant characters. 16. The growth rate of MET line was slower than that of Suwon #19. 17. MET line and Suwon #19 were both heavily infected with black streaked mosaic virus.