• Title/Summary/Keyword: reciprocal cross

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Analysis of Gene for Major Quantitative Characters in Silkworm, Bombyx mori (가잠의 주요 양적 형질에 관한 유전분석)

  • 손봉희;정원복
    • Journal of Sericultural and Entomological Science
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    • v.34 no.1
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    • pp.21-29
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    • 1992
  • In the experiment, gene actions were analyzed for seven silkworm varieties in order to obtain basic information on their genetic improvement by diallel crosses. The results obtained were summarized as follows : in analysis of variance, significantly maternal and reciprocal effects were observed for all character except female cocoon shell percentage and female pupal weight. Over-dominance was shown by Vr-Wr graphic analysis in three characters such as female cocoon weight, female and male pupal weight, and partial dominance in five characters such as male cocoon weight, cocoon shell percentage in both female and male. Component of genetic varience analyzed for five characters such as male cocoon weight, cocoon shell weight, cocoon shell percentage in both female and male showed that additive effects were higher than dominant effects, and female cocoon weight showed dominant effects higher than additive effects. Heritability of narrow sence was higher more than 0.51 and heritability of broad sence was higher more than 0.77 in all characters except for female pupal weight. The directions of dominance were negative for female cocoon shell weight and somewhat higher for female and male cocoon shell percentage. Meanwhile cocoon weight, pupal weight in both female and male showed positive in the direction of dominance.

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Breeding of New Varieties by Ovule Culture of Intergeneric Hybrid in the Aurantioideae (속간교잡 후 배주배양에 의한 감귤류 신품종 육성)

  • 이만상
    • Korean Journal of Plant Tissue Culture
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    • v.22 no.5
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    • pp.261-266
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    • 1995
  • This study was carried out to develop new varieties which are dwarf and tolerant to winter cold in the Aurantioideae by intergeneric crossing. to do that, the reciprocal crosses of Hwanggeumyooza and trifoliate orange, yooza and trifoliate orange were done and in vitro immature ovule culture of their hybrid was carried out .The callus formation from immature ovule was good in order of Hwanggeumyooza, Hwanggeumyooza $\times$ tifoliate orange, yooza, and trifoliate orange and best at 1 to 3 mg/L NAA+0.5mg/L zeatin on MT medium. In vitro germination percentage of 20week old hybrid of Hwanggeumyooza $\times$ tifoliate orange and trifoliate orange $\times$ Hwanggeumyooza were 41.3% and 37.7, respectively. The phenotype of hybrid (95%) of Hwanggeumyooza $\times$ trifoliate orange and that (100%) of trifoliate orange $\times$ Hwanggeumyooza were similar to that of trifoliate orange. After Hwanggeumyooza was pollinated by pollens of trifoliate orange, the pollen tubes grew on stigma after 3h of pollination and entered into micropyle after about 24~28 h. One gamete in pollen was fused with polar nuclei after 2 days and other one fused with egg nucleus at 3days after pollination. The fruit set percentage by intergeneric crossing was 14.0% in Hwanggeumyooza $\times$ trtfoliate orange and 17.5% in trifoliate orange $\times$ Hwanggeumyooza. The fruit set percentages of Hwanggeumyooza. and trifoliate orange were 34.2% and 39.5% by artificial self-fertilization, 34.2% and 39.5% by artificial cross fertilization, 3.1% and 1.4% by parthenocarpy and 13.0% and 3.0% by natural fertilization, respectively. The somatic and gametic chromosome numbers of Hwanggeumyooza, yooza, and trifoliate orange were 2n=18 and n=9.

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The Genetic Analysis of Quantitative Characters in the Silkworm by Diallel Cross of Four Inbred Lines Differing in Silk Yield (견생산력이 다른 계통간의 Diallel Cross에 의한 누에 양적 형질의 유전분석)

  • 손기욱;유강선
    • Journal of Sericultural and Entomological Science
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    • v.29 no.2
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    • pp.7-14
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    • 1987
  • Extensive studies were undertaken to analyze the genetic basis of economically important quantitative characters in the silkworm by diallel crosses of four inbred lines differing widely in silk yielding ability. Some differences between the reciprocal corsses were detected in cocoon weight, cocoon shell weight, cocoon filament length and cocoon filament weight in case the parental lines were greatly differenent each other in silk yielding ability. The general combining ability (GCA) varied with the inbred lines and M242, a Chieese sexlimited larval marking variety showed high GCA value in the economic characters, such as cocoon yield, cocoon weight, cocoon filament length and weight, and raw silk percentage. The highest heterosis effect, about 13% to 14% was seen in cocoon and raw silk yield and it was low in cocoon reelability and raw silk percentage with less than 1%. It is advisable to improve highly heritable quantitative characters such as larval duration, cocoon shell weight, cocoon filament length and raw silk percentage by means of selection, and to select single crosses with high heterosis effect for cocoon weight and cocoon yield which show overdominance. Genetic correlation should be considered when more than two characters are targets for improvement and selecting high cocoon shell weight is effective to breed high silk yielding varieties. It is difficult to improve cocoon reelability because of low heritability (0.11) and its negative correlation with cocoon-silk quality.

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A Study on the Development of Career Exploration Support Centers' Measurement Indices of the Performance (진로체험지원센터 성과평가 기준 개발)

  • Chang, Heajung;Yun, Yeju
    • 대한공업교육학회지
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    • v.45 no.2
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    • pp.46-69
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    • 2020
  • The primary purpose of this study was to develop performance evaluation indices for measuring the results of the work and performance of the career exploration support centers. For the study, First, to describe the current status of the management system across the 228 centers, examine the staff's perceptions of the current evaluation method and system of each center, and analyze the needs of measuring indices of each center for its performance evaluation, a cross-sectional survey method was employed. Second, relevant literature was reviewed. Next, measurement indices were developed employing the Delphi method with a panel of 15 experts in developing instruments of accomplishment. Based upon the conclusion of this study, The measurement indices developed in this study focuses on the core measurement indices. These indices include a checkbox of necessary and unnecessary in each item so that each local department of education or each center can select indicating items (indices) according to its own needs. The newly developed measurement indices consists of four domains to assess: (1) Institutional competencies-goals, budget, system, and resources, (2) Practitional competences-qualities of programs, administration of experiential career program providers, promotion of centers and programs, management of human resources such as instructors or guides, and establishment of community-center cooperative networking system, (3) Accomplishments-finding new experiential career program providers, the number of participants such as schools and students, reciprocal system, and the degree of participants' satisfaction with the center and programs, and (4) specialized indicators-extra scores for center-based specialized programs.

Species and Hybrid Identification of Genus Coreoleuciscus Species in Hwnag-ji Stream, Nakdong River Basin in Korea (낙동강 상류 황지천에 서식하는 쉬리속(genus Coreoleuciscus) 어류 집단의 종 동정 및 잡종 판별)

  • Song, Ha-Yoon;Kim, Jae-Hun;Seo, In-Young;Bang, In-Chul
    • Korean Journal of Ichthyology
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    • v.29 no.1
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    • pp.1-12
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    • 2017
  • A natural hybrid of interspecific between the Coreoleuciscus splendidus and C. aeruginos (Cypriniformes: Cyprinidae) was captured in the Hwang-ji Stream, a tributary of the Nakdong River basin in Korea. An interspecific hybrid between C. splendidus and C. aeruginos was genetically identified based on morphological characteristics and the sequence analysis of nuclear recombination activating gene 1 (RAG1) gene (1,334 bp) and mitochondrial cytochrome c oxidase subunit 1 (CO1) gene (1,551 bp). As a result of morphological variations, the natural hybrid appeared to have an intermediate character between two parental species (C. splendidus and C. aeruginos) in three variations of black array (s) on dorsal, caudal and anal fin rays. Phylogenetic analysis inferred from RAG1 and CO1 sequence data revealed that Coreoleuciscus populations from Hwang-ji stream consist of two pure Coreoleuciscus species and a hybrid individual group. The individuals were clearly identified the cross and reciprocal hybrid by CO1 gene analysis. In RAG1 gene, 13 nucleotide variation loci were detected and the hybrid individuals displayed the double peaks of sequence chromatograms at the 9 diagnostic positions. In this study, molecular data and morphological variations were clearly demonstrated that hybridization did occur between C. splendidus and C. aeruginos. However, F2 hybrid generation and reproductive capacity of F1 hybrid individuals were not demonstrated.

An Empirical Study on Multi-Cultural Family's Housing Satisfaction -With focus on Korean-Chinese in Ansan City- (다문화 가족의 주거만족도에 관한 실증연구 -안산시 중국동포를 중심으로-)

  • Lee, Mu-Seon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.10
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    • pp.323-335
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    • 2017
  • Recently, Korea is facing a trend of a fast-paced change towards a multi-cultural society, accompanied by the consequential increase in population and many changes in the peripheral environment. Particularly, the influx of multi-cultural families in Ansan City is increasing every year, but their housing environment remains in poor conditions. Actually, the research on housing policy for multi-cultural families and their housing satisfaction is restrictive. It is therefore necessary to research on how to overcome this problem, and what realistic policy alternatives are required. The purpose of this study is to present some policy alternatives to improve the housing satisfaction of the Korean-Chinese residing in Ansan City. To this end, this study conducted empirical analysis with a focus on Korea-Chinese multi-cultural families living in Ansan City through a questionnaire. As the analysis method, this study conducted frequency analysis, descriptive statistical analysis, cross analysis, and regression analysis, and used the statistical package-SPSS 20.0 as an analysis tool. As a result of the research, first, it was found that their awareness of the government housing policy is insufficient; second, they had a lot more hardships in housing due to the problem of the rising house prices caused by urban development & regeneration; third, in terms of housing tenure type, there was a higher proportion of a lease on a deposit basis and monthly rent than owner-occupied housing. Hence, this study drew the conclusion that the Korean-Chinese multi-cultural family's housing environment needs to be improved and policy support is required for Korean-Chinese. In addition, this study gives great significance in providing these research results as basic materials which make it possible to inquire into mutually reciprocal practice plan and strategic alternatives for a multi-cultural families from now on.

Korean Caregiver's Perceived Benefits and Costs of the Coresidence with the Elderly Parents - focused on Rural and Urban Difference - (부양의식, 형제자매 지원과 노부모 동거에 대한 혜택-비용 지각 - 도시와 농촌 비교를 중심으로 -)

  • 한경혜;이정화
    • Journal of the Korean Home Economics Association
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    • v.39 no.11
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    • pp.129-144
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    • 2001
  • In spite of rapid sociocultural changes and an increase in the number of nuclear families in recent years, quite many families in Korea still have taken the extended family form where daughter-in-law provides care for the elderly parents. Even though the nature of the inter-generational relationship in Korea is reciprocal in many regards, most of the studies looked at the burden or costs of coresidence with the elderly parents while relatively little attention has been given to the positive side of the coresidence. This study is an attempt to fill this gap in the area. The purpose of this study is to examine not only the costs but also benefits of the coresidence with the elderly parents. We also explore whether there is a rural-urban differences in costs and benefits of coresidence and related factors. For the purpose, data were gathered from 876 daughters-in-law of three generational family both in rural and urban area, using structured questionnaire. The statistical methods used for data analysis were descriptive statistics, cross tables, and regression analysis with SPSS/PC+ program. The major findings of this study were as follows: Marital and economic status of the elderly parents, age, job status and filial responsibility attitude of caregiver, sibling support, and coresidence duration were the significant variables predicting the level of perceived benefits. Marital status of elderly parents, income, job status, educational level, and filial responsibility altitude of caregiver, residence region affected the level of perceived costs. Rural-urban differences are found in many aspects of coresidence experiences and related factors. Rural caregivers receive higher level of the sibling support, have more traditional final responsibility altitude and perceived less costs and more benefit than urban caregivers. There also are differences in the factors influencing the level of perceived costs and benefits between rural and urban area. Level of sibling support and final responsibility attitude have significant impact on both the perceived costs and benefits. But there are differences in terms of that perceived costs and benefits of urban caregivers are affected by job status of caregivers while those of rural caregivers are affected by educational level of caregivers and marital status of elderly. The results confirm that Korean caregivers experience both positive and negative aspects of coresidence and shows that the nature of the inter-generational relationships differ between rural and urban Korea.

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Genetic Analysis for Traits at Birth and Weaning in Mice (Mouse의 생시(生時) 및 이유시(離乳時) 형질(形質)에 대(對)한 유전분석(遺傳分析))

  • Choi, Kwang Soo;Park, Hang Kyun;Hyun, Byung Hwa
    • Current Research on Agriculture and Life Sciences
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    • v.3
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    • pp.158-165
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    • 1985
  • The study was conducted to obtain some genetic information for breeding of mice. Average performance, heterosis and genetic variance were estimated with 362 progenies from a full diallel cross of four lines of mice (BALB/c, CBA, C3H and C57BL). The progenies were reared at the Experimental Animal Farm. College of Agriculture, Kyungpook National University from November, 1984 to February, 1985. Data for litter size. sex ratio, body weight and weaning rate were analyzed into heterosis effects, and genetic variance with Hayman's model. The results obtained are summarized as follows : 1. Average performance was 7.54 in litter size, 53.20 % in sex ratio, 1.55 g in birth weight, 10.45 g in weaning weight and 94.13 % in weaning rate. 2. The estimated heterois was 6.97% in litter size, 7.26 % in sex ratio, 6.08% in birth weight, 3.54% in weaning weight and 2.05% in weaning rate, respectively. 3. Additive gene effects were not observed in litter size, sex ratio, birth weight, weaning weight and weaning rate. In litter size and weaning weight, dominance effects were observed, which were shown due to individual crosses in litter size and were shown mean dominance effects of parental line in weaning weight. Mat-Maternal effects appeared in birth weight and weaning weight, and reciprocal effects were observed in weaning weight.

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Genetic Studies on Some Silkworm Characters by the Diallel Cross II. Analysis of Heterosis and Combining Abilities (이면교잡에 의한 잠체형질의 유전분석 II. 조합능력의 검정)

  • 장권열;한경수;민병열
    • Journal of Sericultural and Entomological Science
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    • v.22 no.2
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    • pp.1-7
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    • 1981
  • Diallel crosses among six silkworm varieties were used as the materials by the randomized block design. and combining ability tests were conducted to determine the relationships between parents and their F$_1$ hybrids. The six parents and their 30 F$_1$ crosses were evaluated for five quantitative characters in each female and male silkworms. Mean values of period(days) of larval stage in mid-parent were more than those of each F$_1$ hybrids. Highly significant differences were shown in the total cocoon weight and weight of cocoon layer of silkworms in F$_1$ hybrids of 111$\times$114, 111$\times$ yunil, 114$\times$yunil and those of reciprocal crosses. From the results, it was recognized that varieties A(111), D(114) and F(yunil) were useful varieties as the parents in breeding of silkworms for increasing the total cocoon weight and weight of cocoon layer, etc. Differences among crosses in apparent degree of heterosis existed for total cocoon weight of cocoon layer and cocoon layer ratio, etc. Mean square values of GCA (general combining ability) were more greater than those of SCA(specific combining ability) for period(days) of larval stage, period (days) of 5th instar and cocoon layer ratio of silkworms. The effects of GCA were differ from parents and characters and the effects of SCA were also differ from parents, characters and crosses.

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The Test of Combining Ability and Heterosis on the Silkworm(Bombyx mori) Breeding (누에 견.사질에 관한 잡종강세 및 조합능력검정)

  • 문병원;한경수
    • Journal of Sericultural and Entomological Science
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    • v.36 no.1
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    • pp.8-25
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    • 1994
  • The study was conducted to obtain the genetic information on heterosis and combining ability of the quantitative characters for F1 hybrid breeding in silkworms. Six parental varieties and each set of 30 diallel crosses in F1's were used as materials, and bred on the randomized complete block design with three replications. Fourteen characters were observed with the twenty samples in each tray. The data were analyzed for (1) heterosis and combining ability in F1 hybrid. The heterosis in the weight and the length of cocoon showed positively high at 24.51%, and 23.4%, respectively and the weight of the whole cocoon as well as the weight of the whole cocoon layer showed a siginificant heterosis ranging from 15.56% to 15.71% and from 17.14% to 19.01%, but the fifth and the total instar period showed negative heterosis. It was found that the combination between, C70XRomogua and N9 X Romogua showed highly a negative heterosis on the fifth instar period and for the cocoon weight. The female of N9+Sansuian and the male of Romogua X Sansurian have a high heterosis effect, on the cocoon shell weight, and Sansurian X Romogua(reciprocal) on the length and the weight of cocoon filament with no regard to sexuality. The significant maternal and cytoplasmic effect on heterosis of the cocoon weight and the cocoon shell weight were observed with the combinations, N9 X C5, N63 X C70 and on the length of the cocoon filament with the combinations, Sansurian X N63, Sansurian X C5, Sansurian X C70 and N9 X C70, N63 X C70 on the weight of cocoon filament. As mean squared of GCA, SCA and RCA were significant with these combining ability for all characters resulted from additive and non-additive altogether and there is a significant difference between reciprocals. Sansurian showed a negative GCA effect on the fifth and total larval duration, but the higher positive GCA effects took places with varieties N9 and C5 on the length, width, weight of cocoon, cocoon shell weight, percentage of cocoon shell weight, length and weight of cocoon filament, percentage of raw-silk with no regard to both generations and silkworm sexuality. The values of SCA between the cross combinations varied generation-wise and sex-wise. It was shown that SCA value for the fifth instar period was highly negative for Sansurian X C70, Romogua X C70, Sansurian X C5, Romogua X C5, but it was positive effect on the cocoon weight, cocoon shell weight with N9 X C5, and C70 X Sansurian, on the length of cocoon filament with N9 X C5, Romogua X Sansurian on the weight of cocoon filament between Romogua and N63 and on the percentage of raw-silk between the combination of Sansurian X Romoga.

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