• Communications for Statistical Applications and Methods
• /
• v.8 no.1
• /
• pp.65-71
• /
• 2001

In this paper, optimal block designs for complete diallel crosses are proposed. These optimal block designs are constructed by using triangular partially balanced incomplete designs derived from symmetric balanced incomplete block designs. Also, it is shown that block designs for complete dialle crosses derived from complementary designs of triangular designs are optimal block designs.

• Korean Journal of Breeding Science
• /
• v.40 no.1
• /
• pp.8-14
• /
• 2008

A complete diallel cross was performed to determine the inheritance of allelopathic potential and combining ability of six rice germplasm that showed different level of allelopathic potential against barnyardgrass. Parents and F1 of 30 crosses were assessed for allelophatic potential in field condition. Barnyardgrass (Echinochloa crus-galli (L.) Beauv. var. frumentaceae) was used for rice allelopathic potential indicator which was observed in height and shoot dry weight, then suppression percentage were calculated by comparing to barnyardgrass grown in control plot (no rice). It was found that general combining ability showed no significant effect, whereas specific combining ability and reciprocal effect were significant. Variance analysis confirmed that genetic control of allelopathic potential in rice against barnyardgrass was mostly directed by dominance gene effect. The dominant genes were associated with high allelopathic potential and recessive genes were associated with low allelopathic potential. Heritability in broad sense for barnyardgrass dry weight suppression was around 41%; whereas for barnyardgrass height suppression was 51%. However, heritability in narrow sense was very low. The finding suggests that accumulation of genes associated with allelopathic potential would be a strategy to develop promising varieties in reference with the specific combining ability of cross combinations.

• Proceedings of the Korean Statistical Society Conference
• /
• 2002.05a
• /
• pp.165-170
• /
• 2002

Sometimes we have two groups of inbred lines and there are only interest in gca comparisons within group($p_{1}$) and group($p_{2}$) and not between two groups. For example, suppose there two Lab, each of the 2 Labs have obtained the best lines. For this purpose we now give a method of constructing block designs for diallel cross experiments and we will explain how to calculate efficiency. Then we show the efficiencies in the table.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.25 no.1
• /
• pp.31-38
• /
• 1980

This experiment was carried out to study the heterosis and the GCA and SCA effects for days to heading of F 1 populations produced from eight wheat cultivar diallel. Greater heterosis for early heading was exhibited under the high temperature condition than under the low temperature conditions, and same results were also observed under short day condition rather than long day conditions. There are highly significant mean for GCA and SCA at all environmental conditions. Yecora F70 was showed the greatest effect, and Bezostaya and Blueboy were exhibited less effects of CCA for early heading. Significant GCA effect was expressed at high temperature and short day condition, indicating that this condition provides a better opportunity to select the materials for earliness. Selections of combination with greater effect of SCA for early heading such as Suweon 169 \times Yecora F70 were discussed for practical utilization.

• Journal of Korean Society of Forest Science
• /
• v.75 no.1
• /
• pp.55-66
• /
• 1986

A complete diallel cross using ten varieties of Corylus avellana was made to select the best general combiners and the best specific combiners for each characteristic of each variety. The variety "Barcelona" showed the best general combining ability in kernel yield per hectare and the combinations, between Kara and Badem, between Badem and Barcelona, between Sivri and Barcelona, between Sirri and Barcelona, between Palaz and Barcelona, between Tombul and Kara, between Barcelona and Sivri, between Fiukuken2 and Hukuken3, and between Hukuken3 and Hukuken2, showed the best specific combining abilities in kernel yield. The other characteristics such as fruiting rate, pericarp thickness, weight/nut, kernel weight/nut, kernel ratio, and kernel yield per tree or hectare were also compared between the combinations.

• Asian-Australasian Journal of Animal Sciences
• /
• v.18 no.6
• /
• pp.767-771
• /
• 2005

In order to understand the molecular basis of chicken heterosis in reproduction traits, mRNA differential display (DDRT-PCR) methods were used to analyze the differential gene expression of ovary tissue between hybrids and their parental lines in a 4${\times}$4 diallel cross, involving 4 chicken breeds, which were White Plymouth Rock (E), CAU Brown (D), Silkies (C) and White Leghorn (A). Total of 331 differential displayed cDNA bands from 1,161 were displayed in the 4${\times}$4 diallel cross combinations with 30 pairs of primers, which shows the differences of gene expression between hybrids and their parental lines were very obvious in quantity and quality. Seven types of differential expression patterns were found: Co-dominance expressed pattern (T1), under-expression of parental fragments in hybrids (T2), over-expression of parental fragments in hybrids (T3), hybrid-absence expressed pattern (T4), single parentspecific expressed pattern (T5), dominant expression fragments of single parent in hybrids (T6), hybrid-specific expressed pattern (T7). Correlation analysis indicated that there were significant correlations between the pattern of T3 and the heterosis percentage of egg number of 32-week and 42-week old chickens(p<0.01), while there were negative significant correlations between the pattern of T7 and the heterosis percentage of egg number of 32-week and 42 week-old birds (p<0.01).

• Journal of Life Science
• /
• v.15 no.3 s.70
• /
• pp.365-373
• /
• 2005

The quantitative inheritance of some yield characters in Gosyium spp was carried out by means of a $10\times10$ diallel cross. In this study, 45 combinations of $F_1\;and\;F_2$ generations were genetically analyzed through 10 different cultivars diallel cross population of cotton (Gosyium spp) at an experimental field. The results of Vr-Wr graph analysis of six characters such as number of boll, boll weight, lint weight per boll, 100 seeds weight, fiber fineness and fiber length in those combinations by the Hayman's method were as follow: 1. The significant difference was observed from the genetic variance of all the examined characters. 2. On based the Vr-Wr graphical analysis, $F_1$ showed a complete dominance in all the experimental characters except boll weight, lint weight per boll and fiber fineness, but the dominance degree and gene arrangement of $F_2$ were somewhat different from those of $F_1$.

• Korean Journal of Agricultural Science
• /
• v.49 no.4
• /
• pp.1033-1040
• /
• 2022

The current experiment was conducted to evaluate the effect of diallel crossbreeding on the body weight and laying performance of Korean native chicken from hatch to week 40. A total of 1,000 one-day-old chicks were allotted to 10 cages per crossbreeding treatment with 10 birds per cage on a random basis and then raised until 16 weeks and subsequently moved to layer battery cages and raised until 40 weeks. Ten crossbred treatments (YC, YD, YF, YK, CD, CF, CK, DF, DK, FK) that were obtained from the diallel crossbred of five pure lines were used in the current experiment. The body weight and mortality were measured biweekly from hatching to week 20 and every four weeks from week 20 to week 40. The number of eggs was measured daily. YC and YD crossbreeds showed a higher body weight (p < 0.05) and FK crossbreed showed a lower body weight (p < 0.05) during the whole xperimental period. The week 20 weight range was 1,501 to 1,729 g and the week 40 weight range was from 1,829 to 2,179 g. Earlier onset of egg-laying was noted in the YC and YD groups whereas late onset was observed for the DF and DK groups. YK reached its peak earliest at week 25 with 89.15% while the DK crossbreed attained its peak at week 36 with 89.69%. The YC and YD crossbreeds showed the improved body and egg-laying performance. Conclusively, there are variations in the body weight and laying performance of Korean native chickens with diallel crossing.

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

• Journal of Life Science
• /
• v.7 no.1
• /
• pp.59-65
• /
• 1997

In this experiment, gene actions were analysized for seven barley parents in order to obtain basic information on their genetic improvement by diallel crosses. The results obtained were summarized as follows. In analysis of variance, additive, dominant, maternal and reciprocal effects were observed significantly for culm length, tiller number, number of spiked per plant, culm diameter, awn length, leaf width, number of grains per spike, and 1000 grain weight. Over-dominance was shown by Vr-Wr graphic analysis in five characters such as tiller number, number of spikes per plant, length of flag leaf, number of grains per spike, and 1000 grain weight, and partial dominance in four characters such as culm length, culm diameter, awn length, and leaf width. Component of genetic varience analyzed for four characters such as culm diameter, awn length, length of flag leaf, and leaf width showed that additive effects were higher than dominant effects. Culm length, tiller number, number of spikes per plant, number of grains per spike, and 1000 grain weight showed dominant effects higher than additive effects. The narrow-sense heritability for awn length, leaf width, and number of grains per spike showed high values as more than 0.62, while broad-sense heritability for culm length, number of spikes per plant, culm diameter, awn length, leaf width, number of grains per spike, and 1000 grain weight showed high values as more than 0.65.