• Title/Summary/Keyword: general combining ability

Search Result 110, Processing Time 0.026 seconds

Manifestation of Hybrid Vigour and Combining Ability in Polyvoltine $\times$ Bivoltine Hybrids of Silkworm, Bombyx mori L.

  • Rao, D.Raghavendra;Singh, Ravindra;Premalatha, V.;Kariappa, B.K.;Rekha, M.
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.4 no.1
    • /
    • pp.23-30
    • /
    • 2002
  • The general and specific combining abilities and hybrid vigour of seven polyvoltine breeds [BL24, BL62, BL6S, BL67, BL68, BL69, and Pure Mysore (PM)] with five bivoltine breeds (NB4D2, CSR2, CSR5, CSR18 and CSR19) were evaluated in a line ${times}$ tester design by analysing six quantitative traits viz., fecundity, yield 110,000 larvae both by number and weight, cocoon weight, shell weight and cocoon shell ratio. ANOVA estimates showed significant effects for all the traits indicating the role of both additive and non- additive gene actions. Estimation of GCA revealed that the breed BL67 exhibited significant positive effects toy all the six traits followed by BL68 for four important economic traits viz., fecundity, cocoon weight, shell weight and cocoon shell ratio. Among testers, CSR5 showed significant GCA effects for five traits whereas CSR2 exhibited for shell weight and shell ratio. Three hybrids viz., BL67${times}$ NB4D2, BL67 ${times}$CSR5 and BL67${times}$ CSR19 excelled in four quantitative traits for SCA. Majority of the hybrids expressed positive hybrid vigour for cocoon yield/10,000 larvae by weight, cocoon weight and shell weight. Four hybrids namely PM ${times}$ NB4D2, BL67 ${times}$NB4D2, BL67${times}$ CSR5 and BL67${times}$ CSR19 manifesting positive hybrid vigour for five economic traits were adjudicated as best Heterotic hybrids and recommended for commercial exploitation to increase the silk yield.

Estimation of Heterosis from Strain Crosses of White Crosses and White Plymouth Rock for Certain Economic Traits (백색코니쉬와 백색플리머드록 계통간 교배단계별 경제형질에 대한 잡종강세 발현율 추정)

  • 정일정;정선부;연성흠
    • Korean Journal of Poultry Science
    • /
    • v.12 no.2
    • /
    • pp.75-82
    • /
    • 1985
  • This study was carried out to estimate combining abilities and heterosis in White Cornish and White Plymouth Rock. The data were obtained over an 8weeks period from 3rd Oct., 1984 to 28th Nov. 1984 at the Livestock Experiment Station. A total of 810 birds, composed of 369 pure strains, 270 two-way crosses, and 180 fourway crosses were average amount of heterosis expressed as a ratio was 1.63% for livability, 5.47% for body weight at 8 weeks, 5.57% for weight gain from day old to 8 weeks and -5.98% for feed requirement. Specific combining ability were statistically significant for all of the traits examined in this study. Although the general combining ability was not significant for any of the traits, strain A appears to be superior to other strains.

  • PDF

Genetic Variance and Combining Ability of Shattering and Growth Characters by Diallel Crosses of Sesame (이면교잡에 의한 참깨의 탈립성 및 생육형질의 유전변이와 조합능력)

  • Kim, Dong-Hwi;Kang, Chul-Whan;Shim, Kang-Bo;Park, Chang-Hwan;Lee, Sung-Woo;Seong, Nak-Sul
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.51 no.7
    • /
    • pp.652-657
    • /
    • 2006
  • Combining ability and heterosis for $F_{1}$ population obtained $5{\times}5$ half diallel cross in sesame were estimated for six quantitative characters. The parental varieties used for diallel cross were Yangbaek and Ansan of normal type, Suwon 177 and 195 of placenta adhesion type (PA) and SIG960320-5-1-1 of indehiscent type (ID). PA and ID type are shattering-resistant sesames and Yangbaek and Ansan are shattering sesames. The high heterosis of $F_{1}$ hybrids was expressed in the number of capsules per plant (NC), grain yield per plant (GY) and number of branches per plant (NB). Shattering.ate (SR) showed high positive heterosis toward increase of seeds shattering in all the combination of $F_{1}$ generation which was presumed because the characters connected with shattering resistance of seeds were governed by recessive gene. At the analysis of combining ability, highly significant general combining ability (GCA) effects were observed on all the characters in $F_{1}$ generation, significant specific combining ability (SCA) effects were observed on the NC, GY and SR. GCA variances were greater than SCA variance, which suggested that additive gene effects were greater than other nonadditive gene effects. Considering the estimated GCA effects, Suwon 195 (PA type) was found to be good parent for SR and GY, SIG960320-5-1-1 (ID type) was poor for GY and plant height. SCA effect for NC was great in Yangbaek/Suwon 195, SCA for GY was great in Ansan/SIG960320-5-1-1, and SCA for decrease of SR was great in Ansan/Suwon177.

Correlation and Combining Ability of Plant Spreading Chracteristics in F1 Hybrids by Diallel Cross in Petunia hybrida (페튜니아 일대 잡종에서 덩굴성 관련형질의 상호관계 및 조합능력)

  • Song, Cheon Young
    • FLOWER RESEARCH JOURNAL
    • /
    • v.17 no.3
    • /
    • pp.179-184
    • /
    • 2009
  • The correlation and combining abilities related with plant spreading characteristics of plant height, plant width, stem length, internode length, number of stem, number of leaves, and number of flower were studied in the $F_1s$ of 10 crosses from the partial five-parent diallel cross in Petunia hybrida. The plant width showed highly positive correlation with internode length, and number of flower. The mean squares of general combining ability(GCA) and specific combining ability(SCA) were highly significant for plant width, number of stem, number of leaves, and number of flowers. The mean square values of GCA were greater than those of SCA for all the characters, showing preponderance of additive gene actions for these characters. The lines of D and I for plant width and length of stem showed relatively high GCA effects. The crosses of $D{\times}I$, $F{\times}I$, and $G{\times}I$ exhibited high SCA effects on plant width, especially $G{\times}I$ effected in internode length and number of flower. The broad sense heritability was generally high compared to narrow sense one. Plant width and stem length, and internode length related to spreading growth showed the higher heritability than the other characters in the broad and narrow sense.

Inter-Relationship and Combining Ability of Plant Growth in F1 Hybrids of Petunia hybrida (페튜니아 일대 잡종에서 생육관련 형질의 상호관계 및 조합능력)

  • Song, C.Y.;Hong, K.H.;Kang, Y.K.
    • Journal of Practical Agriculture & Fisheries Research
    • /
    • v.3 no.1
    • /
    • pp.85-93
    • /
    • 2001
  • The inter-relationship and combining abilities of characters for leaf length, leaf width, branch number, leaf number, leaf area, fresh weight and dry weight were studied in the F1 combination of 15 crosses from the partial six-parent diallel cross in Petunia hybrida. The leaf area, fresh weight and dry weight showed high positive correlation together with the other growth characters such as leaf length, leaf width, branch number, leaf number. The mean squares of general combining ability(GCA) and specific combining ability(SCA) were highly significant for all the growth characters. The estimates of variance components of SCA were greater than those of GCA for all the characters, showing preponderance of non-additive gene actions for these characters. GCA effect was high in the lines of D and G for leaf length and fresh weight, and in the lines of C and D for branch number, leaf number, leaf area and fresh weight. The crosses of D×E, D×G, and E×G exhibited high SCA effect for all the growth characters such as leaf length, leaf width, branch number, leaf number, leaf area, fresh weight, and dry weight. The broad sense heritability was generally high compared to narrow sense one in the 7 characters. The highest heritability of the broad and narrow sense was shown in the leaf width and dry weight.

Development of the Quotient Equation of the Hypothesis Evaluating Ability by Analysis of the Pre-service Elementary School Teachers' Knowledges for Evaluating Hypothesis on a Woodpecker Task (딱따구리 과제에서 초등예비 교사들의 가설 평가 지식에 대한 분석을 통한 가설 평가 능력 지수 산출식의 개발)

  • Lee, Jun-Ki;Lee, Il-Sun;Kwon, Yong-Ju
    • Journal of Korean Elementary Science Education
    • /
    • v.27 no.1
    • /
    • pp.49-59
    • /
    • 2008
  • The purpose of this study was to invent a quotient equation which could quantitatively evaluate individual's hypothesis evaluating ability. The equation was induced by the analysis of the classification types about hypothesis evaluation knowledges generated by 15 pre-service elementary school teachers and the construction of the quotient equation on hypothesis evaluating ability. The hypothesis evaluation task administered to subjects was dealt with the woodpecker behavior. The task was initiated by generating hypothesis on the following question: 'Why don't woodpecker have brain damage after pecking wood?' Subjects then were asked to design and perform experiments for testing hypothesis. Finally they were asked to evaluate their own hypothesis based on the collected, analyzed and interpreted data. The knowledges generated from their evaluating hypothesis were analyzed by 4 major categories (richness, type, level and accuracy). Then, a general equation which could quantitatively and systematically evaluate individual's hypothesis evaluating ability was invented by an inductive process. After combining all the categories the following quotient equation was proposed; '$VQ\;=\;{\sum}(TE_n\;{\times}\;AE_n)\;{\times}\;LE$'. According to this results, woodpecker task and hypothesis evaluating ability quotient equation (VQ) which invented in this study could be applied to a practical use of measuring students' ability of scientific hypothesis evaluation.

  • PDF

Genetic Analysis of Growth Response to Cold Water Irrigation in Rice

  • Han, Long-Zhi;Koh, Hee-Jong
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.45 no.1
    • /
    • pp.26-31
    • /
    • 2000
  • This study was carried out to obtain the basic information for breeding cold-tolerant rice varieties with high yield-productivity through wide crosses between indica and japonica rice. Genetic analysis was conducted using 55 F$_1$s obtained from half-diallel crosses among eleven cultivars of various origin including indica and japonica rice. Screening for cold tolerance was done with cold-water irrigation after transplanting until ripening stage. Both general combining ability (GCA) and specific combining ability (SCA) effects were highly significant in all characters associated with dry matter accumulation at 30 and 50days after cold-water irrigation (DAC). The variance of GCA was much larger than that of SCA in plant height, shoot dry weight per plant (DWP), crop growth rate (CGR) and cold-water response index (CRI) of these characters except CRI of shoot dry weight per plant. The DWP, CGR and CRI of these characters of Gaochan 102, Tong88-7 and TR22183 were markedly higher than those of the others. GCA effects of these varieties on DWP, CGR and their CRI were also higher than those of the others, indicating that they are useful as promising parents for breeding cold-tolerant varieties. Analysis of genetic parameters for 11$\times$11 half-diallel F$_1$s revealed that inter-locus gene interaction were concerned in the expression of plant height at 50 DAC, CRI of DWP at 50 DAC, and CRI of CGR, and that intra-locus gene interaction for plant height and the other characters were partial dominance and over-dominance, respectively. Narrow-sense heritability (h$^2$$_{N}$) was the highest in plant height as 0.729, and the lowest in CRI of DWP at 30 DAC as 0.048, suggesting that selection for cold tolerance will be quite effective in case that the selection criterion is the performance itself.f.

  • PDF

Combining Ability Analysis and Selection Effectiveness for Tolerance to Cold-Induced Sterility in Rice (벼 장해형 내냉성의 조합능력검정과 선발효과)

  • Huhn Pal, Moon;J. Neil, Rutger
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.33 no.4
    • /
    • pp.412-419
    • /
    • 1988
  • Cold-induced sterility is a problem of rice (Oryza sativa L.) production in temperate regions and high elevation tropics. The present study was conducted to measure combining ability, determine character associations. and to evaluate effectiveness of F$_2$selection for tolerance to this type of cold injury. The F$_1$, F$_2$, F$_3$ and reciprocal backcross F$_1$ populations of a nine-parent diallel were grown at Davis, California. a relatively cool location for rice. Additive genetic variance was predominant but some non -additive genetic variance existed for cold tolerance. Good general combining ability (GCA) was generally associated with the cold tolerant parents, 'M-201', and 'L-201', and poor GCA with the most susceptible parent. 7703008. Sterility was positively correlated with late heading. negatively with mature plant height. and negatively with spikelet number. Of the three agronomic characters, heading date had the greatest influence on sterility. Selection of F$_2$'s in seven crosses involving M-101, the most cold-tolerant parent, was effective for increasing cold tolerance. Realized heritability estimates for cold tolerance averaged 0.53, and observed selection response for cold-induced sterility averaged -9.4 percentage points.

  • PDF

Virtual Flux and Positive-Sequence Power Based Control of Grid-Interfaced Converters Against Unbalanced and Distorted Grid Conditions

  • Tao, Yukun;Tang, Wenhu
    • Journal of Electrical Engineering and Technology
    • /
    • v.13 no.3
    • /
    • pp.1265-1274
    • /
    • 2018
  • This paper proposes a virtual flux (VF) and positive-sequence power based control strategy to improve the performance of grid-interfaced three-phase voltage source converters against unbalanced and distorted grid conditions. By using a second-order generalized integrator (SOGI) based VF observer, the proposed strategy achieves an AC voltage sensorless and grid frequency adaptive control. Aiming to realize a balanced sinusoidal line current operation, the fundamental positive-sequence component based instantaneous power is utilized as the control variable. Moreover, the fundamental negative-sequence VF feedforward and the harmonic attenuation ability of a sequence component generator are employed to further enhance the unbalance regulation ability and the harmonic tolerance of line currents, respectively. Finally, the proposed scheme is completed by combining the foregoing two elements with a predictive direct power control (PDPC). In order to verify the feasibility and validity of the proposed SOGI-VFPDPC, the scenarios of unbalanced voltage dip, higher harmonic distortion and grid frequency deviation are investigated in simulation and experimental studies. The corresponding results demonstrate that the proposed strategy ensures a balanced sinusoidal line current operation with excellent steady-state and transient behaviors under general grid conditions.

STUDIES ON THE GENETIC ANALYSIS AMONG BURLEY, FLUE-CURED AND SUN-CURED TYPE TOBACCO 1. HETEROSIS, CORRELATION AND COMBINING ABILITY OF $F_1$ HYBRID (버어리종, 황색종, 양건종, 담배의 유전분석에 관한 연구 I. $F_1$의 잡종강세, 상관 및 조합능력)

  • 한철수
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.7 no.2
    • /
    • pp.99-109
    • /
    • 1985
  • The present studies were carried out to obtain some basic informations of the breeding of tobacco varieties. Genetically divergent 8 varieties, 3 flue-cured, 2 burley and 3 sun-cured tobaccos, were used in half diallel cross. In order to analyze the heterosis, combining abilities, modes of inheritance and correlations for some agronomic and chemical characters, 8 parents and 28 $F_1$ were tested. The results obtained were summarized as follows: The percentages of heterosis for stem diameter, internode length and total sugar content in $F_1$ hybrid were 3.6%, 3.1% and 10.6%, whereas these for days to flower, total alkaloids and leaves per plant were -6.3%, -6.9% and -5.0%, respectively. Yield had significant positive genotypic correlations with plant height, days to flower and leaf length, but negative with internode length and total sugar content. It also had significant prositive phenotypic correlations with plant height, days to flower, leaves per plant, leaf length, leaf width and leaf shape index (Leaf length/leaf width). General (GCA) and specific combining abilities (SCA) for all characters of $F_1$ hybrid were significant. The effects of GCA were positive on yield, plant height, stem diameter, leaves per plant and days to flower of Burley 21. And those were positive on yield, leaf shape index and plant height, but negative on leaves per plant and total nitrogen of Hicks. The effects of SCA for yield and leaves per plant were greater than those of others on the combinations of Coker 139 and Burley type, respectively.

  • PDF