• The Korean Journal of Applied Statistics
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• v.15 no.2
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• pp.367-379
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• 2002

In this paper, the method of constructing incomplete block designs for comparing general combining abilities of p inbred lines for partial diallel crosses is proposed. These partial diallel crosses block designs are constructed by using m-associate class partially balanced incomplete block designs with block size 2 and balanced incomplete block designs. Also, the efficiencies of block designs obtained through this method are tabulated for number of lines 24 or less.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.25-33
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• 1978

7 parent varieties and 21 $_{x}\textrm{F}_1 and $_{x}\textrm{F}_2 hybrids from 7 X 7 partial diallel crosses were used as the materials, and degree of heterosis was studied in 9 agronomic characters of rice. Degree of heterosis was more remarkable in $_{x}\textrm{F}_1 hybrids than $_{x}\textrm{F}_2 hybrids. and significant differences were showed in many hybrid generations. and also over dominance could be shoo wed in eight characters except 1000 kernel weight of rice.

• Korean Journal of Poultry Science
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• v.48 no.2
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• pp.69-80
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• 2021

We conducted a 4 × 4 diallel cross-mating test using 934 chickens from four grandparent stock lines to develop a new synthetic breed of Korean native chicken. The mean values, combining ability, and reciprocal effects on survival rate, body weight, and hen-day egg production were analyzed. In phenotypes, most chickens have yellowish-brown, reddish-brown and mixed color feathers. The average survival rate was 86.8±12.3%, with the highest in YH combination. Specific combining ability (SCA) had a greater effect on survival rate than general combining ability (GCA), and the SCA of HY combination was the highest. The 16 cross-combinations were distinctly divided into three weight groups according to their genetic characteristics. At 12 weeks of age, GCA showed a greater effect on weight than SCA, and the SCA of FH combination was the highest. The age at first egg laying was 157 days, and the crosses reached sexual maturity faster than the pure lines. The egg production rate was highest in SY at 79.5±2.1%. The GCA and SCA for hen-day egg production were similar, and the SCA was highest in the HS and FY combinations. The reciprocal effect showed that the offspring's egg production rate was high when S and Y were maternal parents in almost all combinations. In conclusion, FH and HF combinations, which have excellent growth performance, are the most desirable paternal parent stock strains, and FY, FS, HY, and SY combinations, which have excellent laying performance with moderate weight, are the preferred maternal strains.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.133-141
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• 2023

We conducted a 5 × 5 diallel cross-combination test using 1,060 chickens from pure lines of Korean Rhode-C, -D, Korean Leghorn-F, -K, and Korean Native Yellowish-brown chicken (KNC-Y) to develop a new Korean native chicken layer breeder. The laying performance and combining ability, including livability, body weight, age of first egg-laying, hen-day egg production, and egg weight, were analyzed. The livability from birth to 48 weeks was 72.1±24.0%, with the highest observed in the YC and the lowest in the DK combination (P<0.01). The YC combination exhibited the highest general combining ability (GCA), while the YD combination showed the highest specific combining ability (SCA). Regarding body weight, combinations involving Leghorn showed lighter weights compared to combinations with Rhode and KNC-Y (P<0.01). Additionally, the offspring from the KNC-Y combination reached sexual maturity earlier than those from the Rhode combination. The hen-day egg production was 70.7±12.0%, with the highest seen in the CK combination at 86% (P<0.01). The effects of GCA and SCA on hen-day egg production were similar, with the SCA being highest in the YD combination and the GCA being highest in the Rhode-C. Significant differences in egg weight were observed among the combinations, with the eggs from Rhode and Leghorn combinations being heavier than those from combinations with KNC-Y (P<0.01). In conclusion, the YC and YD combinations, characterized by excellent livability, are highly desirable paternal strains, while the CF and CK combinations, with excellent laying performance and moderate egg weight, are preferred maternal strains for Korean native chicken layer breeders.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.34-39
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• 1978

Partial dominance was exhibited by flowering(heading), panicle length, panicle numbers, $F_1$ag leaf length, 1000 kernel weight in $F_1$ and $F_2$ hybrids by 7 \times 7 and 5 \times 5 diallel crosses. Over dominance was exhibited by culm length, flag leaf width, appearance degree of panicle in $F_1$ generation of the crosses, and also over dominance was exhibited by kernel weight in $F_2$ generation of the crosses.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.58-64
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• 2008

A complete diallel cross was performed to determine the inheritance of 1,000 grain weight of brown rice and cyanidin-3-glucoside (C3G) content and combining ability of five pigmented rice that showed different level of C3G content. Parents and F1 of 20 crosses were evaluated for 1,000 grain weight of brown rice and C3G content which extracted from pigmented rice grain with 0.1% trifluoroacteic acid (TFA) in 95% EtOH. For 1,000 grain weight of brown rice and C3G content, both additive and dominant gene effects were detected and the dominance was partial and there were more dominant alleles than recessive ones. Genetic parameters pointed out that there are significant additive and dominant effects and the additive effect is bigger than the dominant one for both grain weight and C3G content. The frequency of negative alleles were higher than positive alleles. Narrow sense heritability estimates were 0.66 for grain weight of 1,000 brown rice and 0.70 for C3G contents. General combining ability (GCA) effects and specific combining ability (SCA) effects were highly significant and GCA effects were drastically higher than SCA ones. It indicates that the inheritance of the C3G contents is controlled mainly by additive genetic factor.

• Journal of Sericultural and Entomological Science
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• v.28 no.1
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• pp.24-29
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• 1986

A set of 21 crosses of F1 generation by diallel crosses from seven parent silkworm, Bombyx mori L. were used as materials to estimate genetic parameters such as gene action and combining ability. Experiments were conducted in 1985, and three characters, which are weight of cocoon, weight of cocoon layer and ration of cocoon layer, were observed. The data were analyzed for each character by Jinks', Hayman's and Griffing's methods. The result obtained are summarized as follows : 1. In Vr-Wr graphical analyses, weight of cocoon was found to be inherited in over dominance, and weight of cocoon layer and ration of cocoon layer were observed as partial dominance. 2. Estimate of additive component of variance(D) was greater than those of dominance component of variance(H) for weight of cocoon layer and ratio of cocoon layer, and positive values of F were observed for all characters. 3. Mean squares of general combining ability were higher than those of specific combining ability. 4. Variety Jam 107 was expressed as the highest GCA effects for three characters, and high SCA effects for all characters were observed in combinations of 113 $\times$Jung 14 and Jam 107 $\times$Jung 14.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.287-293
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• 1985

Degree of heterosis and gene distributions of several agronomic characters of rice were studied with F$_1$ and F$_2$ generations of 9-parent partial diallel cross in 1983-1984. Degree of heterosis was greater in F$_1$ hybrids than F$_2$ hybrids for culm length, panicle length and number of panicle and the heterobeltiosis could be observed in culm length and number of panicle from several crosses. Incomplete dominance was exhibited by culm length, panicle length and number of panicle in F$_1$ and F$_2$ generations.

• Korean Journal of Poultry Science
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• v.44 no.3
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• pp.189-198
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• 2017

This study was conducted to develop a new synthetic breed of Korean native chicken. The combining ability and reciprocal effects for production traits were estimated on 1,157 hens from a $5{\times}5$ diallel cross-mating design using grand parent stock (GPS) lines of Korean native chicken. Body weight, viability, age at first egg laying, egg weight, and hen-day egg production were measured and analyzed. The results showed that the general combining ability (GCA) of the survival rate during laying periods was -9.6 to 11.1, with the highest value obtained in the W strain. Additionally, the GCA of the body weight at 12 weeks was -209.7 to 162.2, with the highest value obtained in the F strain. The GCA for age at fist egg laying was estimated to be -2.8 to 3.7, while the GCA of egg weight was -0.91 to 0.96, and the GCA of hen-day egg production was -4.9 to 6.0. In the estimation of specific combining ability, the YW combination showed the highest survival rate, FW showed the highest body weight at 12 weeks, and GW showed the highest hen-day egg production. The reciprocal effects were significantly different among crosses for almost all productivity traits. In identical breeding combinations, differences in ability were observed when the maternal or paternal breeds were switched. The mean value based on combining ability was higher in WY, WF, and GW combinations for survival rate; GF, HG, and HF combinations for body weight at 12 weeks; and GW, YW, and FW combinations for hen-day egg production. It is concluded that the GF and HF combinations, which have excellent growth performance and moderate survival rate, are the most desirable paternal parent stock (PS) strains, and the GW and FW combinations, which have great laying performance and moderate body weight, are the most desirable maternal PS strains.

• Korean Journal of Poultry Science
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• v.44 no.2
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• pp.123-134
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• 2017

This study was conducted to establish new synthetic lines of Korean Native Chicken. We performed $5{\times}5$ diallel crossings with GPS lines of Korean Native Chicken for the selection of parent stock. The production traits including viability, body weight, age at first egg laying, egg weight, hen-day egg production, and hen-housed egg production were measured and analyzed for 25 crosses with 1,157 hens. The heterosis effects of these traits were also estimated. The results showed that the average survival rate during laying periods was 67.7% in the pure lines and 77.1% in the crosses. The 25 cross combinations were shown to be distinctly divided into three groups according to body weight; nine crosses in the high-weight group, 12 crosses in the medium-weight group and four crosses in the light-weight group. The average body weight at 12 weeks of age was $1,873.8{\pm}43.0g$ in the high group, $1,595.4{\pm}56.6g$ in the medium group and $1,152.7{\pm}24.7g$ in the light group, and $1,560.2{\pm}339.3g$ in the pure lines and $1,640.9{\pm}213.7g$ in the crosses. In terms of egg production performance, the age at first egg laying was $139.7{\pm}4.9$ days in the pure lines and $135.8{\pm}5.1$ days in the crosses. The average egg weight was $52.3{\pm}1.6g$ in the pure line and $53.0{\pm}1.6g$ in the crosses. The average hen-housed egg production from 20 to 40 weeks was $58.3{\pm}12.9$ eggs in the pure line and $69.2{\pm}10.4$ eggs in the crosses. The average heterosis effect was 16.9% for survival rate, 5.4% for body weight at 12 weeks, -2.7% for age at first egg laying, 1.3% for egg weight, and 14.3% for hen-day egg production. Generally, the heterosis effect for viability and egg production traits was higher than that for growth trait. On the basis of these results, it is expected that the selection of the HF combination, which had excellent growth performance, is the most desirable as the paternal strain, and the selection of GW and FW combinations, which had excellent laying performance, are preferable as the maternal strain.