• Journal of the Korean Society of Tobacco Science
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• v.6 no.2
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• pp.207-214
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• 1984

In order to obtain the basic information for the successful breeding of aromatic tobacco (N. tabacum L.), the combining ability and the mode of inheritance in 28 $F_2$ hybrids by diallel crosses between Korea local and oriental varieties were investigated. Estimates of general combining ability were significant for all characters investigated, and the specific combining ability was significant for stalk height, leaves per plant, leaf length, leaf width and days to flower. The partial dominance was exhibited by all characters investigated as well as additive effects were larger than dominance effects for all characters.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.31-38
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• 2000

Seven flue-cured tobacco(Nicotiana tabacum) varieties and their 21 progenies in Fl and F2 generation, half diallel crosses(no reciprocal), were tested for the degree of heterosis and combining abilities in sucker producing character according to topping and suckering treatment. Significant difference in number and weight of sucker was observed among seven cultivars. The values of general combining ability(GCA) were greater than those of specific combining ability(SCA) in weight and number of sucker in F$_1$ generation. In topping and suckering plot, Cocker 86, McNair 944, and Va 115 revealed the significant negative GCA effects for number and weight of sucker, but By 104 and Speight G-28 did positive GCA. Without topping and suckering, GCA effects for sucker weight in Cocker 139 and Cocker 86 were negative and those for sucker number in Va. 115 were also negative. Negative SCA values in sucker weight could be observed in F$_1$ generation of Cocker 86 X BY 104 and Speiht G-28 X Cocker 86, in F$_2$ of Hicks $\times$ Speight G-28 and McNair 944 $\times$ BY 104 in topping and suckering plot. SCA in F$_1$ of McNair 944 X Cocker 86 and Speight G-28 X Cocker 139 was negative without topping and suckering. The value of heterosis in sucker producing character of F$_1$ hybrids was positive

• Journal of Sericultural and Entomological Science
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• v.32 no.1
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• pp.17-30
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• 1990

A 6${\times}$4 top-cross set was made from the ten silkworm parental lines selected by the first principal component scores. They were also analysed for the relationship between the combining ability and the first principal component score. The highest general combining ability effects were detected in the parental lines of Japanese, N39 and chinese, C46, for the most quantitative characters in the study. The first principal component score of factors related to silk productivity in the parents was significantly and positively correlated to the general combining ability of the twelve characters such as cocoon yield, cocoon weight, cocoon shell weight, cocoon shell percentage, duration of the 5th instar larvae, total larval period, length of a bave, weight of a have, non-breaking length of a bave, non-breaking weight of a have, raw silk percentage, and neatness. Similarity distance (D$^2$) was related to the specific combining ability of the characters such as cocoon yield, non-breaking length of a bave, non-breaking weight of a have, non-breaking ratio of a bave, raw silk percentage, neatness. From the results, it is possible to predict the general combining ability effects by the principal component scores for the 12 characters of the parents related to silk productivity.

• Communications for Statistical Applications and Methods
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• v.9 no.3
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• pp.733-741
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• 2002

A class of block designs for general combining ability comparisons within two groups of inbred lines in diallel crosses is given. These block designs are constructed by using balanced block designs obtained by cyclically developing a single initial block. Also, the efficiencies of block designs are tabulated for number of lines 26 or less.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.250-256
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• 1992

This study was carried out to obtain basic genetic informations in pea(Pisum sativum L.). A series of field experiments were carried out with seven pea cultivars and F$_1$ hybrids for three years. Based on the information collected from a set of diallel crosses, the behaviours of inheritance of seed yield and ten major agronomical characters were observed by the estimation of heterosis and combining ability. Heterosis for seed yield per plant was 79% and those for yield components such as number of seeds per plant, number of pods per plant, stem length, stem diameter, number of branches per plant, also showed relatively high values. General combining ability(GCA) and specific combining ability(SCA) were significantly different among major agronomic characters, and the variances of GCA were higher than those of SCA latter. Among the tested cultivars, Alderman was found to be the most promising parent based upon the GCA effects on the seed yield and yield components. The crosses of Sugar Ann$\times$Alderman, Wando$\times$Alderman and JI 1198$\times$Chinju ＃6, showed the highest SCA effects on seed yield and yield components.

• Journal of Sericultural and Entomological Science
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• v.37 no.1
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• pp.10-15
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• 1995

Genetic characterization of Sri Lankan silkworm bivoltine population has not been at-tempted so far, since its sporadic introduction of bivoltine strains into the island, starting from the 1950's. Genetic structure of Sri Lankan population of mulberry silkworm Bombyx mori was investigated through estimation of general (GCA) and specific combining ability(SCA) and heritability(${h^2}_B$), on the economic quantitative characters from leading 8 inbreds and their 28 F1's in a half diallel cross, in an attempt to utilize the estimates in determination of future breeding methods and to predict the breeding value over the phenotypic value. It was found that the breeding population of the bivoltine silkworm in Sri Lanka has still maintained considerable amounts of additive gene action as well as nonadditive. For some time in the future, both breeding strategies of "selection without inbreeding" and also "inbreeding followed by crossing" should therefore be effective in genetic improvement of economic characters investigated. In addition, superior combiners in general and in specific F1′s were identified for each of 6 economic characters, to be immediately utilized in selection and also in cross breeding programs in Sri Lanka.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.424-427
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• 2001

Combining ability study was carried out on the components of synchronization in maturity and determinate growth habit in mungbean, using 6$\times$6 diallel cross. Both additive and non-additive gene effects were found conditioning the inheritance of days to first flower, days between first pod and 90% pod maturity (DDd1), plant height from first pod stage to 90% pod maturity (DDhl, DDh2, and DDh3). Only non-additive gene action was important in degree of determination from first pod stage to 90% pod maturity (DDd2). While only additive action was important in plant height at first flower. The predominant additive gene action was observed in all traits but non-additive was significant in only DDd$_2$. For synchronization in maturity, determinate growth habit, and their components, the best combiners were NM92, VCl560D, and NM89, whereas the best indeterminate combinations were NM92 $\times$ NM89, NM92 $\times$ VCl560D, and NM92 $\times$ ML-5.

• Journal of Sericultural and Entomological Science
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• v.29 no.1
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• pp.31-38
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• 1987

The genetic analysis was caried out on the boiling-off ratio of cocoon layer, and the amounts of sericin and fibroin in the F1 generation from the diallel crosses of silkworm. The result obtained were as follows : 1. Boiling-off ratio and the amounts of sericin adn fibroin in male and female were over dominqnce and partial dominance, respectively. 2. The additive effect of gene was higher then the dominance effect in the amounts of sericin and fibroin in male and female, and in boiling off ration in female. 3. The direction of dominance in the amounts of sericin and fibroin in male and female was positive and that in boiling off ratio negative. 4. The effect of three characters on the combining ability was significant and their general combining ability was higher than the specific combining ability.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.10
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• pp.1-13
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• 2022

This paper empirically explores the predicting ability of the newly proposed smooth transition (ST) time-varying combining forecast methods. The proposed method allows the "weight" of combining forecasts to change gradually over time through its unique feature of transition variables. Stock market returns from 7 countries were applied to Ad Hoc models, the well-known Generalized Autoregressive Conditional Heteroskedasticity (GARCH) family models, and the Smooth Transition Exponential Smoothing (STES) models. Of the individual models, GJRGARCH and STES-E&AE emerged as the best models and thereby were chosen for constructing the combined forecast models where a total of nine ST combining methods were developed. The robustness of the ST combining forecasts is also validated by the Diebold-Mariano (DM) test. The post-sample forecasting performance shows that ST combining forecast methods outperformed all the individual models and fixed weight combining models. This study contributes in two ways: 1) the ST combining methods statistically outperformed all the individual forecast methods and the existing traditional combining methods using simple averaging and Bates & Granger method. 2) trading volume as a transition variable in ST methods was superior to other individual models as well as the ST models with single sign or size of past shocks as transition variables.

• Journal of Life Science
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• v.15 no.2 s.69
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• pp.211-214
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• 2005

The studies were conducted to obtain basic informations on inheritance of some quantitative characters in kidney bean (Phaseolus vulgaris L.). Seven parents (Felibon, Renka, Processor, Kaboom, $BO_{22}$, Local variety $\#1$ and Local variety $\#2)$ and $F_1$ hybrids of 21 crosses from a set of diallel cross among varieties were used to estimate combining ability for eight agronomic characters such as days to flowering, days to maturity, stem length, pod numbers per plant, pod length, grain numbers per plant, 100-grain weight and grain weight per plant. General combining ability (GCA) and specific combining ability (SCA) were significantly different among all characters, and values of GCA were greater than those of SCA in all characters except number of grains per plant. In effect of GCA, Felibon expressed high GCA effect for days to flowering and number of grains per plant. Local variety $\#1$ showed high GCA effect for 100-grain weight and stem length. Local variety $\#2$appeared to high GCA effect for 100-grain weight and grain weight per plant. Processor expressed high GCA effect for days to maturity and grain weight per plant. Kaboom showed high GCA effect days to flowering and days to maturity. $BO_{22}$ appeared high GCA effect for all characters except for days to flowering, days to maturity and stem length. In the SCA effect, crosses of Felibonx Renka and Local variety $\#2{\times}Processor$ exhibited in high negative effect for days to flowering. Thus, these crosses were evaluated to useful for breeding early maturing variety. Crosses of breeding high yield variety were considered of $Felibon{\times}Local$ variety $\#1$, $Felibon{\times}Renka$ and Local variety $\#2{\times}BO_{22}$.