• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.45-52
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• 1996

This study was conducted to know how cold tolerance of rice is inherited. Several crosses were made between cold tolerant and susceptible varieties, and their progenies were evaluated for days to heading, spikelet number per panicle and spikelet fertility under both cold water and natural conditions. In F$_1$ and F$_2$ generations, earlier heading, more number of spikelet per panicle and higher spikelet fertility under the cold condition were dominance, and less delay or reduction in heading days and spikelets per panicle by cold treatment were over dominance or partial dominance, while less reduction in spikelet fertility by cold-water irrigation was complete dominance. Heritability in most characters by cold treatment was high and there was less difference of heritabilities in heading days and spikelets per panicle between cold treatment and natural conditions, while there was much difference of heritability in spikelet fertility between two conditions. Heterosis in spikelet fertility was considerably high, while those in heading days and spikelets per panicle were relatively low. Heterosis in remote crosses was especially larger under the cold-water treatment condition compare with that under natural condition.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.165-169
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• 1998

Anthers of three cross combinations of hot-pepper(Capsicum annuum L.) were cultured on Dumas De Vaulx medium supplemented with some growth regulators. The embryo production efficiency and the diversity for agronomic traits in $A_2$ lines were investigated. The embryo production frequencies of hybrid combinations were ranged from 16.4% to 43.4%, the highest embryo induction combination was DGSH $\times$ C-NH with 43.4% embryogenic efficiency. Among total 275 $A_2$ lines, phenotypic variants were found in six lines, 2.1% variant frequency. The diversity of $A_2$ lines derived from anther culture was different according to the cross combinations. Fruit color was within parental range, no transgressive variation was observed. However leaf color showed transgressive variation. In fruit length, fruit width and fruit weight, one C-HC $\times$ DGSH and DGSH $\times$ C-NH showed great diversity compared with doner parents while Cheokjo 1 $\times$ C-NH crossed with Cheokjo 1 with big fruit shape showed small diversity. Stem length to 1st branch was relatively similer to or longer than donor parents. Stem thick exhibited remarkable diversity. Node number to 1st branch distributed alomost within the range of donor parents in C-HC $\times$ DGSH combination, however great transgressive variations were observed in DGSH $\times$ C-NH and Cheokjo 1 $\times$ C-NH combinations.

• Korean Journal of Poultry Science
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• v.44 no.3
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• pp.189-198
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• 2017

This study was conducted to develop a new synthetic breed of Korean native chicken. The combining ability and reciprocal effects for production traits were estimated on 1,157 hens from a $5{\times}5$ diallel cross-mating design using grand parent stock (GPS) lines of Korean native chicken. Body weight, viability, age at first egg laying, egg weight, and hen-day egg production were measured and analyzed. The results showed that the general combining ability (GCA) of the survival rate during laying periods was -9.6 to 11.1, with the highest value obtained in the W strain. Additionally, the GCA of the body weight at 12 weeks was -209.7 to 162.2, with the highest value obtained in the F strain. The GCA for age at fist egg laying was estimated to be -2.8 to 3.7, while the GCA of egg weight was -0.91 to 0.96, and the GCA of hen-day egg production was -4.9 to 6.0. In the estimation of specific combining ability, the YW combination showed the highest survival rate, FW showed the highest body weight at 12 weeks, and GW showed the highest hen-day egg production. The reciprocal effects were significantly different among crosses for almost all productivity traits. In identical breeding combinations, differences in ability were observed when the maternal or paternal breeds were switched. The mean value based on combining ability was higher in WY, WF, and GW combinations for survival rate; GF, HG, and HF combinations for body weight at 12 weeks; and GW, YW, and FW combinations for hen-day egg production. It is concluded that the GF and HF combinations, which have excellent growth performance and moderate survival rate, are the most desirable paternal parent stock (PS) strains, and the GW and FW combinations, which have great laying performance and moderate body weight, are the most desirable maternal PS strains.

• Korean Journal of Plant Resources
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• v.32 no.5
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• pp.509-518
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• 2019

This study was conducted to investigate single crossing condition of M. sacchariflrous and M. sinensis for breeding of M. ${\times}$ giganteus cultivar. Compared with natural day length condition, cultivation in short day length condition shorten days to heading to 18~27 days in both species. Pollen germination ratio of were 75.8% at 6 o'clock in M. sacchariflorus and 51.9% at 7 o'clock in M. sinensis but decreased to below 10% at 8 o'clock in both species. When cut ears immerged in 150 mL of cut-flowers conservation solution and isolated with covering of white non-woven fabric, flowering and pollen dispersal were persisted for 7 days, and the ratio of pollen germination were above 40% for 4 days. The ratio of self-fertilization of both species were below 2.5%, but open pollenation ratio were above 50%. We obtained 437 seeds with experimental single cross of 14 combinations between tetraploid M. sacchariflorus and diploid M. siensis by application of developed single crossing methods. In the single cross, numbers of seed set were different by mother plants. Thus, the newly investigated single crossing condition will be used to breed M. ${\times}$ giganteous cultivar which is sterile and has superior characteristics of biomass yield.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.1-7
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• 1994

Four tetraploid mulberry lines, Sawonppon No.11, No.13 and No.14, were induced by the colchicine treatment on the shoot tips of seedlings originated from the cross between Yongchonppong and Kaeryanppong. The major characteristics of the tetraploid lines were as follows: Green tip sprouting stage was similar to Kaeryanppong, a medium budding variety. Leaves were medium- to large-sized cordate type. Leaf surface was rougher and stronger than that of the diploid parents. Leaf thickness, leaf area weight and leaf water content were higher than those of the diploid parents. Average branch length was shorter than that of the diploid parents. Internode length and number of lateral branches were similar to the average values of the two parents. Death atop rate of branch was 1.6%~2.5% indicating strong cold-hardiness of the tetraploid lines. Therefore, these lines could be used as sources of cold-hardiness in developing triploid lines.

• FLOWER RESEARCH JOURNAL
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• v.18 no.2
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• pp.147-150
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• 2010

A new cultivar potted miniature rose (Rosa hybrida) 'Tiny Ball' was selected out of cross combination 1999 and 2002 at Gumi Floricultural Experiment Station. Characteristics trials were conducted three times from 2003 to 2006. 'Tiny Ball' came from the combination that '990905' crossed to 'Manish'. New cultivar has pink and white flower color and the shape of flower is similar to tiny ball. The number of flower petals and flowers per pot are more than those of 'POULra022' as comparison cultivar. This cultivar has low plant height without treatment of plant retardant materials, so the high quality grade ratio of potted rose is higher than that of comparison cultivar.

• Korean Journal of Poultry Science
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• v.51 no.2
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• pp.83-95
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• 2024

This study aimed to assess the performance of laying hens across twelve crossbreed strains (i.e., CFCK, CFYC, CFYD, CKCF, CKYC, CKYD, YCYD, YCCF, YCCK, YDCF, YDCK, and YDYC) of Korean native chicken (KNC) and compare them with Hy-Line Brown layers. A total of 287 18-week-old laying hens were placed in battery cages by strains (2-5 birds per pen). Results indicated that the YCYD and YDYC strains exhibited numerically heavier body weights than Hy-Line Brown at week 18-64. CKYC and YDYC strains demonstrated more than 94% viability by week 64. The CFYC strain had an age of first egg laying of 127 days, and the YDCF strain reached an age of 50% egg production at 140 days, both earlier than their parent stock. The YDCF strain showed over 70% egg production for up to 60 weeks. Regarding egg quality, the CKCF and YCCF strains had numerically higher egg weights among the KNC groups at week 24-64, with the YDYC strain showing a darker (P<0.05) eggshell color compared to CKCF at week 40. Moreover, KNC crossbreeds showed a higher (P<0.05) egg yolk ratio than Hy-Line Brown. In conclusion, the YDCF and YCCF crossbreeds exhibited the most desirable new synthetic Korean native commercial layer based on egg production and quality parameters. Therefore, these strains could be a viable substitute for Hy-Line Brown layers.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.298-304
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• 2002

The inheritance of resistance to gall mite(Eriophys macrodonis) in boxthorn cultivars was studied with plants infected in open field. Segregation of the F$_1$ generation from crosses between resistant cultivars(Japan 1 and China 1) and susceptible line(CL42-56) hits a 3 resistant : 1 susceptible ratio, and the segregation ratio was 15 : 1 in cross between Japan 1 and China 1. It is concluded that gall mite resistance seemed to be controlled by two duplicate genes(El and E2), such that E1e1E2e2 symbolize the genotypes of China 1 and Japan 1. However, F, generation from Chungyanggugiza and CL42-56 cross did not showed clear segregation pattern but continuous variation was observed against gall mite resistance when resistance was determined on the basis of the percentage of galled leaves. Results indicated that the inheritance of resistance in Chungyanggugiza may be polygenic and complex. Also, Japan 1 and China 1 has a strong potential as a source of gall mite resistance, and Chungyanggugiza showing less resistance still has a valuable source.

• Korean Journal of Plant Resources
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• v.18 no.2
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• pp.309-314
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• 2005

This study was carried out to obtain the basic informations on the flowering habit, pollination patterns and seed setting in Hosta plantaginea Aschers. Flowers came out in the night with white color. Almost fertilization seemed to be out by wind in early and full flowering. But bearing pods by insects and fertilization rate by wind were increased by interval of flowering and particular scent slowly decreased in after flowering. Bearing pods and seeds setting rate were $65.0\%,\;40.9\%$ per peduncle after artificial pollination, and also $33.3\%,\;24.3\%$ in natural pollination, respectively. The flowering times was all around seven to eight o'clock at night and optimum temperature for pollination was $25{\sim}28^{\circ}C$.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2000.05a
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• pp.35-38
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• 2000

본 논문에서는 퍼지 제어기의 설계를 위한 다중 돌연변이 연산자를 갖는 Niche Meta 유전 알고리즘을 제안한다. 제안된 알고리즘에서 유전자는 유전 알고리즘에 사용되는 교배율이나 돌연변이율과 같은 구조 매개변수와 퍼지 제어기의 입, 출력 소속함수를 나타내는 매개변수로 구성된다. 제안된 알고리즘은 부개체군들에 대해 퍼지 제어기의 소속함수의 매개변수를 최적화시키는 지역적 탐색을 수행하면서 전체 개체군에 대해서 최적의 구조 매개변수에 대한 전역적인 탐색을 수행한다. 다중 돌연변이 연산자는 지역적 진화의 결과에 따라 진화에 가장 적합한 돌연변이 방법으로 선택된다. 제안된 알고리즘의 효율성을 입증하기 위해 2 자유도를 구륜이동 로봇에 대한 모의 실험을 수행한다.