• International Journal of Reliability and Applications
• /
• 제2권2호
• /
• pp.131-135
• /
• 2001

Two general methods of construction leading to several series of universally optimal block designs for complete diallel crosses are provided in this paper. A method of constructing variance balance designs is also given.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제2권2호
• /
• pp.111-117
• /
• 2001

Screening of fifteen bivoltine silkworm breeds of Bombyx mori Linn at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85${\pm}$5% resulted in the identification of eight thermo-tolerant breeds. The survival and cocoon shell ratio of the tolerant breeds ranged from 72.7 to 78.7% and 20.0 to 20.1% respectively. The tolerant breeds comprised of four oval breeds and four dumb-bell breeds. Eight foundation crosses prepared by crossing the oval and dumb-bell parents among themselves were screened at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85{\pm}5%. The performance of the foundation crosses on 11 economic characters were analysed by employing Multipie Trait Evaluation Index method. Four foundation crosses which scored average index value > 50 were selected as breeding parents and breeding initiated for the evolution of thermo-tolerant bivoltine silkworm breeds. The methodology and the results of the foundation crosses reared both at 31{\pm}1$^{\circ}C$ and at $25{\pm}1^{\circ}C$ temperatures, are discussed.

• 한국양식학회지
• /
• 제19권2호
• /
• pp.99-108
• /
• 2006

Sex of the Nile tilapia Oreochromis niloticus is mainly determined by an XX/XY system. However, accumulating evidences suggest the existence of additional sex modifying factors including environmental, autosomal and parental influences. In order to investigate the possibility of parental effects on sex ratios of tilapia progenies, in this study, a series of crosses was carried out using gynogenetic clonal fish, neomales, normal males and females, and YY fish. Crosses between clonal XX male and clonal female have yielded only female progenies and no parental influences were observed. However, in the crosses between clonal males and normal females, female parents were significantly associated with the progeny sex ratios ($X^2$=20.046, 7 d.f., p<0.01). Progeny sex ratios from the crosses between neomales and normal females ($X^2$=60.491, 5 d.f and $X^2$=28.072, 2 d.f.) also showed significant association with female parents (P<0.001). The stability of progeny sex ratios from repeated spawns were confirmed by using 6 different parental pairs. In 16 crosses between normal males and normal females, sex ratios of progenies showed clear maternal influences, and further analysis of the results revealed a negative correlation ($r^2$=0.7718, p<0.05) between the sex ratios of progenies from two different males, indicating a strong paternal influence. No statistically significant relationship between survival rates and sex ratios of progenies was observed in any genotypic groups. Taken together, the influence of parental pairs on progeny sex ratios in this species is evident although the cause of this influence is not clear.

• 한국가금학회지
• /
• 제7권2호
• /
• pp.28-36
• /
• 1980

This study was carried out to estimate combining abilitie or economic traits in layer chickens. The data used in this study were the record of 10 single crosses produced by half diallel cross of 5 lines of Single Comb White Leghorns, such as A, B, C, K and S lines. Total 720 progenies of the crosses were reared at the Poultry Breeding Farm, College of Agriculture, Seoul National University from Feb. 1979 to August, 1980. Combining abilities were estimated by Grilling's mathematical model for the traits; age the first egg, total egg number, egg weight and body weight. The results attained from the studies were summarized as follows; In estimate of combining ability, an age at first egg of BS cross was largely due to significiantly higher general combining ability (G. C. A.) effect of B and S strains than Cand K strains in G. C. A. effect, and to specific combining ability (S. C. A) effect of B and S-trains. AB and BS crosses showed the highest egg Production. AB cross performance was result from high G.C.A. effect of A ana B strains. BS cross performance was result from high G. C. A. effect of B and high S. C. A. effect of BS cross. Specific combining ability effect in egg. weight was not statiscally significiant, but S strain showed high G. C. A. effect. A and B strains in body weight showed significantly low C. C. A. effect. From the above results, BS cross in an age at first egg, AB and BS crosses in egg Production, S strain in egg weight and AB cross in body weight were superior to other strains or crosses.

• 한국잠사곤충학회지
• /
• 제14권2호
• /
• pp.61-65
• /
• 1972

우수한 이화성일본계 N43호를 선출하고 이것과 우량하다고 보는 이화성 중국계 KC, C14, C20과 웅별 자별로 교배시키고 그중에서 우량한 교배종을 선출하려는 목적으로 가잠형질중 가장 중요한 견층량의 유전력의 산출에 의해 선출을 시도한 것이다. 그 결과 다음 같은 결론을 얻게 되었다. 1, KC$\times$N13에 대하여 견층량은 3교배조중 많은 편이나 유전력(h$^2$=0.26)은 낮은 편이며 또한 웅의 유전력은 자의 그것보다 높다. 2. C14$\times$N13에 대하여 견층량에 있어서는 3교배조중 중간이며 또한 유전력(h$^2$=0.3)로 중간이라 이 교배조에서만 자의 유전력이 웅보다 크게 나타나 있다. 3. 020$\times$N13에 대하여 견층량에 있어서는 3교배조중 가장 적은 편이나 유전력(h$^2$=0.35)은 가장 많은 편이다. 또 과거의 3잠기를 통하여 견층비율도 양호하고 기타 충질에서 강한 것으로 우량품종으로 기대할 수 있다고 인정되는 바가 크다.

• 한국연초학회지
• /
• 제3권1호
• /
• pp.49-57
• /
• 1981

To obtain genetic information for breeding aromatic tobacco, broad sense heritabilities, phenotypic, and genotypic correlations were obtained for the following characters : days to frowert, plant height, number of leaves, leaf shape and nicotine. Six pure line varieties and the first and second generations of 5 crosses among them were employed in this study. The heritabilities for number of leaves and nicotine were very high in pure line varieties. However, the heritabilities for days to flower and yield were low in six varieties as well as in F2. Genotypic correlations had higher values than phenotypic did. Heritabilities calculated from segregating generations were lower than those from pure varieties, regardless of crosses involved. Positive phenotypic correlations between yield and plant height were observed in all crosses. Same phenomenon was observed with correlations between days to flower and number of leaves. The genotypic and phenotypic variances and covariances entering into the computation of correlations were used to construct the seletion indices for yield. The use and limitation of selection index was also discussed.

• Asian-Australasian Journal of Animal Sciences
• /
• 제11권1호
• /
• pp.84-88
• /
• 1998

The aim of this study was to describe growth patterns of mice using Gompertz model. Two distinct types of mice, laboratory mouse $CF_{\sharp1}$ (Mus musculus domesticus) and Yonakuni wild mouse (Yk, Mus musculus molossinus yonakuni) were used. From all possible crosses, there were two parental types and two reciprocal $F_1$ crosses obtained. Individual body weights were measured weekly from birth to ten weeks of age on 321 mice. Standardization to six mice was conducted and only first litters were used. Growth curve parameters were estimated to fit growth data. The results showed that growth among genetic groups were significantly different (p < 0.05) for both sexes, in which parental type of $CF_{\sharp1}$ and Yk had the highest and the smallest values, respectively. Meanwhile, reciprocal $F_1$ crosses were intermediate between parental types. It was concluded that Gompertz model provided and excellent fit for the growth data with a high coefficient determination $(R^2 = 0.999)$.

• The Plant Pathology Journal
• /
• 제24권1호
• /
• pp.31-35
• /
• 2008

The presence of Chrysanthemum stunt viroid (CSVd) in seed and pollen of diseased chrysanthemum was demonstrated. In seeds infected male parent from crosses in May, CSVd was transmitted to 6.7% of the progeny seedlings, whereas if the female parent was infected, CSVd transmission rate was between 46.9 and 75.7%. A relatively high incidence of 94.4 to 96.0% seed transmission occurred when both parents were infected. In seeds infected male parent from crosses in December, no progeny seedlings were infected with CSVd, whereas if the female parent did, CSVd transmission rate was 1.5%. When both parents were infected, 6.9% seed transmission was occurred. The seed transmission rate depended on the temperature when the crosses were made. CSVd was not detected in the non-infected female parent pollinated with infected pollen but was transmitted to the progenies. This is the first report of seed-borne transmission of CSVd in chrysanthemum.

• 한국가금학회지
• /
• 제44권2호
• /
• pp.123-134
• /
• 2017

본 연구는 국산 신품종 토종닭을 개발하기 위하여 국내 토종닭 GPS 계통들을 대상으로 $5{\times}5$이면 교배조합 시험을 실시하여 교배조합별 성적을 토대로 최적의 종계 조합을 선발하고자 하였다. 총 25개 교배조합의 암컷 1,157수를 대상으로 주요 생산능력인 생존율, 체중, 시산일령, 난중, 일계산란율 및 산란지수를 조사하고 분석하였으며, 각 조합별 형질들의 잡종강세효과도 추정하였다. 분석 결과, 성계의 평균 생존율은 순계구가 67.7%, 교잡구가 77.1%로 나타났다. 체중 측정 결과, 이들 25개 조합은 뚜렷한 3개의 그룹 즉, 9개의 고체중구, 12개의 중체중구 및 4개의 저체중구로 구분되었다. 12주령 평균 체중은 고체중구는 $1,873.8{\pm}43.0g$, 중 체중구는 $1,595.4{\pm}56.6g$, 저 체중구는 $1,152.7{\pm}24.7g$이었으며, 순계구는 $1,560.2{\pm}339.3g$, 교잡구는 $1,640.9{\pm}213.7g$이었다. 산란능력에 있어 시산일령은 순계구는 $139.7{\pm}4.9$일, 교잡구는 $135.8{\pm}5.1$일이었고, 평균 난중은 순계구에서 $52.3{\pm}1.6g$, 교잡구는 $53.0{\pm}1.6g$이었다. 20주령부터 40주령까지의 산란지수는 순계구가 $58.3{\pm}12.9$개, 교잡구는 $69.2{\pm}10.4$개였다. 잡종강세 효과 추정에 있어 전체 조합에 대한 평균 생존율은 16.9%, 12주 체중은 5.4%, 시산일령은 -2.7%, 난중은 1.3% 및 일계 산란율은 14.3%의 잡종강세율을 나타내었다. 전반적으로 생존율 및 산란형질들의 잡종강세 효과가 성장형질에 비해 높게 나타났다. 이상을 종합할 때 최적의 실용계 생산을 위하여 부계통으로는 우수한 성장능력을 가진 HF 조합구의 선정이 바람직하고, 모계통으로는 우수한 산란능력을 가진 GW 및 FW 조합구의 선정이 바람직하리라 예측된다.

• Communications for Statistical Applications and Methods
• /
• 제8권1호
• /
• 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.