• Asian-Australasian Journal of Animal Sciences
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• 제8권3호
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• pp.295-300
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• 1995

Data from purebred and crossbred cattle involving Holstein and the Local breed in Bangladesh were used to estimate the genetic effects on average daily milk yield and birth weight A total of 877 records on average daily milk yield for 4 types of breed groups and a total of 418 records on birth weight for 5 breed groups were analyzed. Two different methods were applied in this study; the least squares analysis of variance approach and the linear regression approach. Breed group effects were highly significant for both average daily milk yield and birth weight. The result showed that straightbred Holstein produced the highest milk yield and the 7/8 crosses ranked highest in birth weight For the two traits, the additive breed effect was highly significant, whereas the individual heterosis effect was not significant. Furthermore, this study showed a negative maternal heterosis for average daily milk yields and a positive maternal heterosis for birth weight Comparing the breed least squares means obtained from the linear regression approach revealed that straightbred Holstein produced the highest average milk yield and the 3/4 crosses were predicted to have the largest birth weight. It is indicated that the linear regression approach can adequately separate the genetic component of performance, estimate unknown crossbreeding parameters and predict unknown performance of crosses which are not include in the original data.

• Asian-Australasian Journal of Animal Sciences
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• 제13권7호
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• pp.888-893
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• 2000

The present study was conducted to evaluate heterosis effects of body weight and jumping height for successive generations of rotational crossing using two subspecies of mice which are very different in body weight and in genetic relationship from each other. Domesticated laboratory mouse $CF_{{\sharp}1}$ (C) and Yonakuni wild mouse (Y) were used as materials. Two groups of rotational crossing was made according to the parent used at the beginning of crosses, C male$\times$Y female and Y male$\times$C female. These crosses were done to produce the first ($G_1$ and $G_1{^{\prime}}$), second ($G_2$ and $G_2{^{\prime}}$) and third generations ($G_3$ and $G_3{^{\prime}}$) with sire used was alternated. Individual body weights were weighed at 1 (wk1), 3 (wk3), 6 (wk6) and 10 weeks of age (wk10) and jumping heights were measured at six weeks of age (wk6). Only the first litter used. For body weight, results of this study showed that genetic group effects were significant (p<0.01) source of variation at all ages studied. Sex effects were significant (p<0.01) at wk3, wk6 and wk10, but not at wk1. Significant interaction effects (p<0.01) between genetic group and sex were found at wk6 and wk10. The C mice with large maternal effects produced heavier offspring body weight and crosses using sire of this subspecies maintained heavy weight compared to wild Y mouse sire that has small body size. Heterosis tended to exist at the rotational crossing started from Y male C female. For jumping height, effects of genetic group and sex were significant, sire and dam effects (heterosis) exhibited from the first to third generations, and no maternal effects were observed.

• International Journal of Industrial Entomology and Biomaterials
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• 제10권2호
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• pp.153-157
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• 2005

Recently two breeding programs were carried out for isolation of new parental inbred lines in Iran. This study was undertaken in order to estimate the combining ability effects and heterosis of these lines. For this purpose an $8\times8$ diallel cross analysis including eight inbred lines of silkworm with four lines from each program were studied for their five quantitative traits. The results indicated that reciprocal effects appeared insignificant for most of traits. Japanese lines of 111 and 113 were best combiners for shell weight, cocoon weight and shell percentage traits. With respect to pupation rate, Chinese line 110 was the best and according to general combining ability (GCA) and specific combining ability (SCA) variances, it is superior in specific combinations. Hybrid $109\times110$ showed better characters for both productive and viability traits. Hybrids with high heterosis had high SCA too.

• 한국연초학회지
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• 제22권1호
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• pp.31-38
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• 2000

Seven flue-cured tobacco(Nicotiana tabacum) varieties and their 21 progenies in Fl and F2 generation, half diallel crosses(no reciprocal), were tested for the degree of heterosis and combining abilities in sucker producing character according to topping and suckering treatment. Significant difference in number and weight of sucker was observed among seven cultivars. The values of general combining ability(GCA) were greater than those of specific combining ability(SCA) in weight and number of sucker in F$_1$ generation. In topping and suckering plot, Cocker 86, McNair 944, and Va 115 revealed the significant negative GCA effects for number and weight of sucker, but By 104 and Speight G-28 did positive GCA. Without topping and suckering, GCA effects for sucker weight in Cocker 139 and Cocker 86 were negative and those for sucker number in Va. 115 were also negative. Negative SCA values in sucker weight could be observed in F$_1$ generation of Cocker 86 X BY 104 and Speiht G-28 X Cocker 86, in F$_2$ of Hicks $\times$ Speight G-28 and McNair 944 $\times$ BY 104 in topping and suckering plot. SCA in F$_1$ of McNair 944 X Cocker 86 and Speight G-28 X Cocker 139 was negative without topping and suckering. The value of heterosis in sucker producing character of F$_1$ hybrids was positive

• Asian-Australasian Journal of Animal Sciences
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• 제13권10호
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• pp.1353-1358
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• 2000

The three-way rotational crossing experiment has been conducted to evaluate heterosis effects on jumping height and body weight. Yonakuni wild mice (Y) and two genetic groups of $CF_{{\sharp}1}$ (C) and C3H/HeNCrj (H) laboratory mice were used as materials. Reciprocal rotational crossing was made by crossing C male${\times}$Y female and Y male${\times}$C female to produce basic group designated $G_0$ and ${G_0}^{\prime}$, respectively. The females of the $G_0$ and ${G_0}^{\prime}$ were mated to the H sire to produce second generation ($G_1$ and ${G_1}^{\prime}$), and at the following generation the replacement females were mated to Y or C sire according to the basic group to produce $G_2$ to $G_3$ and ${G_2}^{\prime}$ to ${G_3}^{\prime}$. Individual jumping height data at Wk6 and body weight data at 1 (Wk1), 3 (Wk3), 6 (Wk6) and 10 (Wk10) weeks of age were analyzed. The results showed that effects of genetic group, sex and interaction of genetic group by sex were significant (p<0.01) for jumping height. For males, 55.34%~79.17% and 54.46%~78.29% of heterosis were reached at $G_1$ to $G_3$ and ${G_1}^{\prime}$ to ${G_3}^{\prime}$, respectively. While for females at $G_1$ to $G_3$ and at ${G_1}^{\prime}$ to ${G_3}^{\prime}$, heterosis effects were 61.53%~80.42% and 47.79%~85.86%, respectively. For body weight, genetic group was a significant source of variation at all ages studied. Sex effect was significant at Wk3, Wk6 and Wk10, and interaction between genetic group and sex was significant at Wk6 and Wk10 (p<0.01). C sires resulted in the highest body weight of offspring, while H sires were the intermediate and Y sires were the lightest. The significant positive and negative heterosis effects for body weight were exhibited. Crossing involved the Y sires in addition to smaller maternal effects of Y dams tended to result in small heterosis.

• Plant Breeding and Biotechnology
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• 제5권4호
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• pp.371-389
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• 2017

Supplying sufficient rice to growing populations is a global challenge. Hybrid indica rice varieties exploiting heterosis have increased yields, but inter-subspecific crosses between indica and japonica varieties are hampered by sterility. Examination and genetic understanding of yield heterosis in indica/japonica crosses addressing yield barriers are basic requirements. In this study, QTLs for heterosis of yield traits were identified in indica-japonica recombinant inbred lines (RILs) using a total of 178 RILs originating from Dasanbyeo (indica) ${\times}$ TR22183 (japonica) (DT-RILs) and their backcrossed populations. Nine of sixty-six major quantitative trait loci (QTLs) identified in DT-RILs exhibited heterosis. Heterosis QTLs clustered with other traits on chromosomes 1, 4, and 8, and clusters were conserved between different RILs. The clusters contained several known yield enhancement genes/QTLs. Specific heterotic allele combinations contributed to four major heterosis QTLs, particularly for panicle and spikelet number traits. Heterosis for yield and yield-related traits was explained by the harmonized effects of overdominance, dominance, and epistatic interactions in inter-subspecific breeding populations.

• 한국작물학회지
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• 제25권4호
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• pp.73-80
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• 1980

유채의 $F_1$ 수량이 획기적으로 증수되고 있으나 유질과 유박의 성분이 개량된 $F_1$ 육성 보급하는 것이 가장 바람직한 일이라 하겠다. 필자 등은 유질과 유박의 성분이 완전 개량된 세포질 유전자적 웅성불임 계통을 개발한 바 있다. 그러나 화분친으로 이용할 수 있는 성분개량 품종수는 극히 적다. 따라서 국내 육성계통중 성분이 개량된 O-erucic acid, Low-glucosinolate 계통을 화분친으로 이용하는 문제를 검토코저 511육성 계통을 공시하여 $F_1$ 의 임성회복력과 $F_1$의 유용형질의 Heterosis 발현에 대해 조사하였다. 1. MS를 이용한 $F_1$ 임성회복력에서 공시 화분친중 81%의 계통들이 완전 임성회복 유전자를 가지고 있었으며 부분 임성회복 품종이 5%, 비회복 계통이 14%에 불와해서 국내 육성계통들의 임성회복능력이 매우 높은 것으로 밝혀졌다. 2. 비회복 육성계통중 11계통은 Fertility index가 1～3으로 웅성불임 계통의 불임성을 유지하는 능력을 가지고 있어 성분개량 유지계통으로 다양하게 활용할 수 있게 됐다. 3. 이들 MS의 Maintainer는 대부분 핵내 유전자가 Sterile인 Isuzu, Bronowski, 유달, Chisaga에 유래하고 있었다. 4. $F_1$의 Heterosis 발현에서 개화기와 초장은 대부분 중간친보다 늦어지고 긴 경향이며 평균 중간친보다 4일 늦었으며 초장은 45cm나 길었다. 5. 수량구성 형질들은 협장과 1협결실립수만이 중간친보다 짧거나 같은 외는 모든 형질들이 월등히 많고 긴 방향으로 발현하였다. 6. 특히 분지수와 수장 등이 크게 $F_1$ Heterosis를 발현하였을 뿐만 아니라 1 수협수에서도 중간친보다 8개나 더 많았다. 7. 국내 육성계통을 화분친으로 공시한 $F_1$의 10a당 수량성은 511조합의 $F_1$중 91%가 다수성 강세를 발현하는데 그 중에서 10a당 450kg이상 560kg나 증수는 조합만도 11조합이 있었다.

• International Journal of Industrial Entomology and Biomaterials
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• 제13권2호
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• pp.73-77
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• 2006

Combining ability and hybrid vigour analysis was carried out in hybrids between newly developed non-susceptible lines to BmDNV1 and popular bivoltine breeds for certain quantitative traits viz. Pupation rate, Cocoon yield, Cocoon weight, Cocoon shell weight and Cocoon shell ratio, Survival rate against BmIFV and BmNPV. General combining ability (GCA) effects revealed that among the lines CSR2DR was found good general combiner exhibiting significant GCA effects for six characters, out of seven traits evaluated. Among testers CSR28DR was found as good combiner exhibiting significant GCA effects for six traits. Out of 36 hybrids made between $resistant{\times}resistant,\;resistant{\times}susceptible\;and\;susceptible{\times}susceptible$ breeds, one hybrid $CSR21DR{\times}CSR28DR$ exhibited significant SCA effects for six traits. The selected hybrid $CSR21DR{\times}CSR28DR$ also exhibited significant positive heterosis and heterobeltiosis expressions for maximum traits and could be exploited as commercial silkworm hybrid resistant to important viral diseases.

• 한국가금학회지
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• 제24권3호
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• pp.117-126
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• 1997

This study was conducted to estimate the hatching and growing performance, and heterosis of Korean Native Chicken(KNC), Rhode Island Red(RIR) and KNC XRIR crossbred. A total of 1,274 female pullets were produced from KNC, RIR and KNC x RIR crossbred kept in National Live-stock Research Institute, Korea. The experiment was conducted for 20 weeks from Sep. 2, 1995 to Jan. 20,1996. Hatchabilities of KNC dark brown strain x RlR(DR), KNC light brown strain x RlR (LR) and KNC dark black strain x RlR(BR) were 77.3%, 73.6% and 72.5%, respectively. Viabilities up to 20 weeks of age were not significantly (P>0.05) different among purebreds and crossbred. Body weights of DR, LR and BR were 1,890 g, 1,849 g and 1,967 g, respectively, at 20 weeks of age. The feed conversion ratio(feed /gain) of DR, LR, and BR were 5.88, 6.07 and 5.87, respectively, up to 20 weeks of age. Average shank lengths of DR, LR and BR were 97.1 mm, 98.9 mm and 99.4 mm, respectively, at 20 weeks of age. The heterosis effects were estimated to be -0. 48%, and 12.58%, respectively, in fertility and hatchability. Up to 20 weeks of age, the heterosis effects were estimated to be 0.07%, 13.49%, -5.77%, and 3.52% in viability, body weight, feed conversion ratio, and shank length, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제15권6호
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• pp.777-782
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• 2002

Reciprocal effects among local breeds and additive and heterosis effects were estimated for total milk production per lactation (TLP), lactation length (LL) and daily milk yield (DMY). Procedures for an optimum crossbreeding system were examined by comparing various crossbred combinations. Three data sets were chosen from the total records collected from 1962 to 1997. Data set I with a total of 5,938 records composed of 9 breed groups for reciprocal crosses, data set II with a total of 6,064 records composed of 5 breed groups for additive and heterosis effects and data set III with a total of 10,319 records composed of 42 breed groups for optimum crossbreeding system were analyzed. The least squares ANOVA was used. The reciprocal crosses between Red Sindhi and the Bangladeshi Local showed significant difference. When the Red Sindhi was used as cow, the cross was superior to the opposite in terms of the three performance traits. The results showed that additive breed effects on both TLP and DMY were positive and highly significant between Bos indicus and Bos taurus, whereas the individual heterosis effects were not significant. In general, any local breeds were improved two to three times by crossing with the Friesian once or twice. However, the effect was reduced when the grading up with the Friesian was repeated more than twice. On the other hand, when the local breed was crossed with the other breeds such as Holstein and Jersey, the improvement of TLP was less. Crossing the F1 cows with the Friesian bull gave further improvement. Almost the same trends were found also for LL and DMY. The local breeds and their crosses are raised mainly for draft animals, then it is recommended that the crossbreds between the local cows and Friesian are used for dairy purposes and more than 75% Friesian blood is used for beef.