• Journal of Plant Biology
• /
• 제16권1_2호
• /
• pp.39-50
• /
• 1973

The spontaneous and induced reciprocal translocations of chromosomes in higher plants were reviewed and discussion was made on the utilization of this chromosome aberration in the production of seedless hybrid seeds in vegetable crops.

• Plant Biotechnology Reports
• /
• 제2권2호
• /
• pp.145-152
• /
• 2008

Aerides vandarum and Vanda stangeana are two rare and endangered vandaceous orchids with immense floricultural traits. The intergeneric hybrids were synthesized by performing reciprocal crosses between them. In vitro germination response of the immature hybrid embryos was found to be best on half-strength Murashige and Skoog medium supplemented with 20% (v/v) coconut water/liquid endosperm from tender coconut. Determination of hybridity was made as early as the immature seeds or embryos germinated in vitro, using randomly amplified polymorphic DNA (RAPD) markers. Out of 15 arbitrarily chosen decamer RAPD primers, two were found to be useful in amplification of polymorphic bands specific to the parental species and their presence in the reciprocal crosses. However, a decisive profile that can identify the reciprocal crosses could not be provided by RAPD. Amplification of the trnL-F non-coding regions of chloroplast DNA of the parent species and hybrids aided easy identification of the reciprocal crosses from the fact that maternal inheritance of chloroplast DNA held true for these intergeneric hybrids. Subsequent restriction digestion of the polymerase chain reaction (PCR) amplified trnL-F non-coding regions of chloroplast DNA also consolidated the finding. Such PCR-based molecular markers could be used for early determination of hybridity and easy identification of the reciprocal crosses.

• 항공우주시스템공학회지
• /
• 제14권5호
• /
• pp.42-48
• /
• 2020

본 논문은 2행정 피스톤 엔진 기반 발전기 및 배터리로 구성된 드론용 전기추진시스템 설계 과정에 대해 다룬다. 연구의 목적은 하이브리드 시스템의 높은 에너지 밀도를 이용하여 비행시간을 증가 시키고 화석연료 사용량을 줄임으로써 환경 변화에 대처함에 있다. 시스템은 6 kW의 출력을 생산할 수 있고, 엔진 RPM 제어를 통해 부하 요구에 맞는 출력 조절이 가능하다. 또한 배터리를 추가 장착함으로써 출력 보완재 역할 뿐만 아니라 비상시 제한된 시간 내 주 전력으로 사용할 수 있다. 또한 발전기를 엔진 크랭크축에 직접 연결함으로써 설계 복잡성을 줄여 동체 내 공간 활용성을 증대 시켰다.

• 한국수산과학회지
• /
• 제56권1호
• /
• pp.109-115
• /
• 2023

Interspecific hybridization is a beneficial strategy in aquaculture. In this study, diploid hybrids were produced through interspecies hybridization of flounder Platichthys bicoloratus ♀ × starry flounder P. stellatus ♂, which became commercial within a year. These hybrids exhibited an advantage in growth ability, with female hybrids growing twice as large as males at 11 months. Furthermore, hybrid flounders exhibited faster growth rates than starry flounders and reciprocal hybrids. The average growth rate of hybrids was 1.37 and 1.18 times greater than that of starry flounder and reciprocal hybrids at 5.5 months, respectively; Additionally, feed efficiency was 1.21 and 1.10 times higher than that of the experimental groups. The experiments were conducted at five temperatures to determine the optimal fry production method. Six weeks of culture resulted in a significant temperature effect, with maximum growth at 27℃. However, over 90% of the males occurred in the groups at temperatures above 24℃. Therefore, the optimum temperatures for survival, growth, condition factor and frequency of the best-sized fingerling at 13 weeks of age were estimated at 21℃. Thus, hybrid flounders are of great potential for use in the flounder aquaculture industry.

• 한국어류학회지
• /
• 제24권3호
• /
• pp.151-159
• /
• 2012

정교배체인 각시붕어, Rhodeus uyekii (♀)${\times}$떡납줄갱이, R. notatus (♂) 잡종, 그리고 상반교배체인 떡납줄갱이 (♀)${\times}$각시붕어(♂) 잡종을 대상으로 혈액도말을 통한 적혈구 크기, flowcytometry를 통한 세포유전학적인 형질 및 truss dimension과 classical dimension에 의한 외부 계측형질에서의 특성을 부모종간의 차이를 비교하였다. 각시붕어와 떡납줄갱이의 정교배체 및 상반교배체의 계측형질은 일반적으로 이들 유도시 사용된 모계와 부계 종의 중간을 보였다. 정교배체는 14개의 계측형질이 부계의 형질과 유사하였으며 7개의 계측형질이 모계의 형질과 유사하였다. 상반교배체의 경우, 13개의 계측형질이 부계의 형질을, 5개의 계측형질이 모계의 형질과 유사하였다. 정교배체와 상반교배체의 체색소 분포는 중간을 보이나 양친 종을 닮게 나타났다(P<0.05). 적혈구 크기와 DNA 함량은 정교배체와 상반교배체 모두 모계의 적혈구 크기 및 DNA 함량을 따르는 경향이 나타났다(P<0.05). 본 연구에서 파악된 각시붕어와 떡납줄갱이의 잡종 계측형질 및 세포유전학적인 형질은 납자루아과의 관상어 개발시 종간 구별에 유용할 것이다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제2권2호
• /
• pp.103-114
• /
• 1989

Reciprocal crosses were conducted between three strains of Taiwan Country chickens, developed in the National Chung-Hsing University, and two strains of Single Comb White Leghorns, developed in the Taiwan Livestock Research Institute. Traits studied were growing performances, laying performances, egg quality traits and traits concerning disease resistance, including resistance to Marek's disease virus and immune responses to Newcastle disease virus vaccine and to sheep red blood cell. Results indicated that laying performances of Taiwan country chickens were much inferior to White Leghorns, but they matured earlier, their eggs had better shell strength and larger proportion of yolk, and their general disease resistance was much better than White Leghorns. Heterosis were found in laying performances and egg quality traits. The heterosis in laying traits was so large that the hybrid laid as many eggs and as large eggs as did pure strains of White Leghorns. Strategies on the improvement of native chickens and the utilization of genetic merits of native chickens were also discussed.

• 식물분류학회지
• /
• 제39권2호
• /
• pp.74-79
• /
• 2009

The morphological characteristics of leaves, trichomes, and acorns in 8- to 11-year-old reciprocal hybrids of Quercus dentata and Q. serrata were investigated. The reciprocal hybrids had obovate to obovateelliptic leaves that were smaller than those of Q. dentata but similar to Q. serrata in their leaf size, obtuse leaf apex, narrow-tipped leaf base, and shape of small to intermediate-sized serrations. The ray length of stellate hairs was intermediate between those of the parents, and the hairs showed dense growth. Long single hairs are present among the stellate hairs on the abaxial side of the leaves. Therefore, the hybrids of Q. dentata and Q. serrata could be identified by the size and shape of leaves, shape of serrations, and type of leaf trichomes.

• Ocean and Polar Research
• /
• 제42권4호
• /
• pp.303-311
• /
• 2020

In this study, the embryonic development and hatchability of eggs fertilized by the reciprocal hybrids of kelp grouper (Epinephelus bruneus) and red-spotted grouper (E. akaara) were evaluated with the goal of establishing a novel hybrid with enhanced growth and viability during the farming period in the temperate waters of Korea. The fertilization rates were lower for hybrids than for maternal purebreds and were significantly higher in the red-spotted grouper ♀ × kelp grouper ♂ hybrid (RGKG, 89.61 ± 1.58%) than in the kelp grouper ♀ × red-spotted grouper ♂ hybrid (KGRG, 74.82 ± 4.23%, p < 0.05). Unlike the fertilization rates, the hatching rates of fertilized eggs were similar between hybrids and maternal purebreds and did not differ significantly between KGRG and RGKG (72.74 ± 3.60% vs. 75.23 ± 2.20%, respectively, p > 0.05). The embryonic development of the hybrids was similar to that of maternal purebreds; however, irregular cleavage and asymmetric blastoderm were noticeable in the developing eggs of KGRG hybrids. The deformity rates of newly hatched larvae were higher in hybrids than in maternal purebreds and were significantly higher in KGRG than in RGKG (17.47 ± 1.28% vs. 7.11 ± 0.54%, respectively, p < 0.05). These results demonstrate the potential to produce viable larvae from these two hybrids. Although the production efficiency of KGRG was lower than that of RGKG, the fertilization, hatching, and deformity rates make both hybrids useful for further comparative studies regarding economic aspects.

• 한국전산구조공학회:학술대회논문집
• /
• 한국전산구조공학회 2002년도 봄 학술발표회 논문집
• /
• pp.249-256
• /
• 2002

A new optimization procedure with approximate reanalysis module, using the staged hybrid methods with substructuring, is proposed in is study. In this procedure, displacements are calculated with two step mixed procedures. First step is to introduce the conservative approximation, which is a hybrid form of the linear and reciprocal approximation, as local approximation. In the next step, it is combined with the global approximation by reduced basis approach. The quality of reanalyzed quantities can be greatly improved through these staged hybrid approximations, specially for large changes in the design. Overall procedures are based on substructuring scheme. Several numerical examples illustrate the validity and effectiveness of the proposed methods.

• 식물조직배양학회지
• /
• 제25권2호
• /
• pp.135-139
• /
• 1998

연초 N. glauoa(2n=24)와 N. langsdorffii(2n=18)의 종간상 호교잡에 의하여 종간잡종을 획득하였다. N. glauca $\times$ N. langsdorffii 교잡에서는 100%의 F$_1$ 종자를 획득할 수 있었으나, N. langsdorffii $\times$ N. glauca교잡에서는 종자결실이 극히 불량하였다. 그러나 종자 발아율은 모두 양호하였으며, 정상 식물체로 생장하였다. F$_1$식물체의 chromosome수를 조사한 결과 모두 2n=21개로 종간잡종임이 확인되었으며, 엽병의 존재여부 및 형태, 잎의 형태, 꽃잎의 형태와 색깔 및 크기, 화분의 색깔 등의 형태적 특성을 조사한 결과 모두 종간잡 종임을 재차 확인 할 수 있었다. F$_1$잡종식물체에서는 spontaneous tumor인 genetic tumor가 형성되었으며, N. glauca을 모본으로 한 교잡체에서는 생식생장기부터 형성되었고, N. langsdorffii을 모본으로 한 잡종체에서는 생식생장기 이후에만 형성되었다. 특히 genetic tumor 조직을 기내에서 식물호르몬 무첨가 배지에서 배양할 경우 생장이 매우 왕성하였으며 많은 teratoma shoot를 형성하였다. 또한 genetic tumor 조직이 아닌 일반 F$_1$식물체의 잎과 줄기절편도 식물호르몬 무첨가 배지에 접종되었을 때에도 15일경부터 callus가 왕성히 형성되었으며, 30일경부터는 수많은 teratoma shoot가 형성되었다. 식물호르몬 무첨가배지에서 잡종체의 teratoma shoot 형성은 N. langsdorffii $\times$ N. glauca 보다 N. glauca $\times$ N. langsdorffii가 더 양호한 경향을 보였다. Teratoma shoot 중에서는 뿌리는 가지고 있지 않지만 지상부가 정상적으로 자란 shoot를 절취하여 다시 조직배양 할 경우에는 영양생장기에 배양잡종식물체에서 많은 genetic tumor가 형성되었다.