• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.303-313
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• 2020

Rice grain shape is one of the key components of grain yield and market value. An understanding of the genetic basis of the variation in grain shape could be used to improve grain shape. In this study, we developed a total of 265 F₂ individuals derived from a cross between japonica cultivars (Josaeng-jado and Langi) and used this population for quantitative trait locus (QLT) analysis. Correlation analysis was performed to identify relationships between grain traits (GL: grain length, GW: grain width, L/W: ratio of length to width, TGW: 1,000 grain weight). The grain shape was positively correlated with GL and TGW, and negatively correlated with GW. In QTL analysis associated with grain shape, one QTL for GL, qGL5, detected on chromosome 5, explained 20.3% of the phenotypic variation (PV), while two QTLs, qGW5 (PV=36.1) and qGW7 (PV=26.1), for GW were identified on chromosomes 5 and 7, respectively. Evaluation of the effects of each of the QTLs on the grain shape in the population showed a significant difference in the grain size in positive lines compared with the lines without the QTLs. According to the QTL combination of the allelic-types, the grain shape of the tested lines varied from semi-round type to long spindle-shaped type. The results of this study extend our knowledge about the genetic pool governing the diversity of grain shape in japonica cultivars and could be used to improve the grain shape of this species through marker-assisted selective breeding in Korea.

• Korean Journal of Plant Resources
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• v.10 no.3
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• pp.241-246
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• 1997

Linkage maps based on molecular markers are valuable tools in plant breeding and genetic studies. A population of 76 RI lines from the mating of A3733 and PI437.088 was evaluated with Random Amplified Polymorphic DNA(RAPD) and Simple Sequence Repeats (SSR) markers to create soybean molecular linkage map, 302 RAPD and 21 SSR markers were genetically linked and formed forty linkage groups. These linkage groups spanned a genetic distance of 1,775 cM. The average distance between markers was 5.5 cM.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2002.10a
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• pp.220-221
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• 2002

The planktonic shrimp, Acetes chinensis Hansen, 1919 inhabits the coastal areas of the Info-West Pacific, Korea, China, Taiwan, and Japan and is most abundant along the coastal areas of Yellow Sea. Several studies have locally examined aspects of reproductive biology of the species such as reproductive cycle, spawning, maturity, breeding pattern and fecundity. (omitted)

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.249-249
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• 2022

• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.2
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• pp.211-215
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• 2004

Genetic diversity within the natural populations of Daba ecorace of Antheraea mylitta Drury was studied using individual silkworms collected from the South Singhbhum district of Jharkhand state of India with 21 inter simple sequence repeat (ISSR) primers. A total of 148 bands were produced, of which 79% was polymorphic. The pair wise genetic distance among the individuals varied from 0.186 to 0.329. The dendrogram grouped the individuals into 3 major clusters. Nei's heterozygosity analysis revealed 0.265 ${\times}$ 0.18 variability within the population. The high genetic variability present within the natural population of Daba ecorace of A. mylitta is indicative of their adaptational strategy in nature and have much importance for in situ conservation as well as utilization in breeding programs.

• Parasites, Hosts and Diseases
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• v.54 no.4
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• pp.399-405
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• 2016

Poor subsistence farmers who live in a semi-arid area of northern Ethiopia build irrigation systems to overcome water shortages. However, there is a high risk of malaria transmission when increased standing water provides more favorable habitats for mosquito breeding. This is a serious problem because there are many barriers to malaria control measures and health care systems in the area. Using a causal loop diagram and computer simulations, the author attempted to visually illustrate positive and negative feedbacks between mosquito and human populations in the context of Simret, which is a small village located in northern Ethiopia and is generally considered a malaria-free area. The simulation results show that the number of infectious mosquitos increases to 17,215 at its peak, accounting for 3.5% of potentially dangerous mosquitos. At the same time, the number of sick people increases to 574 at its peak, accounting for 15% of local population. The malaria outbreak is controlled largely because of a fixed number of vulnerable people or local population that acts as an intermediate host.

• Korean Journal of Plant Tissue Culture
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• v.27 no.5
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• pp.367-373
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• 2000

We have constructed a molecular linkage map of chili pepper (Capsicum spp.) in an interspecific (C. annuum cv. TF68 x C. chinense cv. Habanero) F$_2$ population of 107 plants with 150 RFLP and 430 AFLP markers. The resulting linkage map consists of 11 large (206-60.3 cM) and 5 small (32.6- 10.3 cM) linkage groups cover-ing 1,320 cM with an average map distance between framework markers of 7.5 cM. Most (80%) of the RFLP markers were pepper-derived clones and these markers were evenly distributed across the genome. By using 30 primer combinations, 444 AFLP markers were generated in the F$_2$population. The majority of the AFLP markers clustered in each linkage group, although PstI/MseI markers were more evenly distributed than Eco RI/MseI markers within the linkage groups. Genes for biosynthesis of carotenoids and capsaicinoids were mapped on our linkage map. This map will provide the basis of studying secondary metabolites in pepper.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1686-1689
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• 2002

Genetic gains and inbreeding coefficients in a Holstein MOET breeding population were predicted under different conditions relating to the distribution of the number of transferable embryos collected per flush using Monte Carlo simulation. The numbers of transferable embryos collected per flush were determined using five distributions (distributions 1, 3, 5, 7 and 9) with different aspects and similar means. Distributions 1, 3, 5, 7 and 9 were assumed to have gamma distribution's parameters ($\alpha$ and $\beta$) of (1 and 4.4), (3 and 1.47), (5 and 0.88), (7 and 0.63) and (9 and 0.49), respectively. Inbreeding rates were statistically significantly different among distributions but genetic gains were not. Relationships between inbreeding rates and variances of family size could be were clearly distinguished. The highest inbreeding coefficients were predicted in distribution 1 with the largest variance of family size, while distributions 5, 7 and 9 with smaller variance of family size had lower inbreeding coefficients.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.6171-6172
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• 2015

A direct connection between certain lifestyle factors and an increased risk of cancer has already been established. Despite well-documented associations, controversial messages on causes of cancer often appear without taking into consideration their impact on the general population. While mainstream coverage of cancer research is clearly welcome, consideration must be given to the risk of transmitting provocative messages with serious negative consequences for cancer research and public health. We must avoid becoming a breeding ground for the misinterpretation of scientific information. Polemical results can stimulate scientific research and progress, but controversial messages encourage confusion and impotence in an increasingly disoriented population. The correct communication of health messages is at least as important as research on risk factors.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1672-1679
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• 2013

Linkage disequilibrium between markers or genetic variants underlying interesting traits affects many genomic methodologies. In many genomic methodologies, the effective population size ($N_e$) is important to assess the genetic diversity of animal populations. In this study, dairy cattle were genotyped using the Illumina BoviveHD Genotyping BeadChips for over 777,000 SNPs located across all autosomes, mitochondria and sex chromosomes, and 70,000 autosomal SNPs were selected randomly for the final analysis. We characterized more accurate linkage disequilibrium in a sample of 96 dairy cattle producing milk in Korea. Estimated linkage disequilibrium was relatively high between closely linked markers (>0.6 at 10 kb) and decreased with increasing distance. Using formulae that related the expected linkage disequilibrium to $N_e$, and assuming a constant actual population size, $N_e$ was estimated to be approximately 122 in this population. Historical $N_e$, calculated assuming linear population growth, was suggestive of a rapid increase $N_e$ over the past 10 generations, and increased slowly thereafter. Additionally, we corrected the genomic relationship structure per chromosome in calculating $r^2$ and estimated $N_e$. The observed $N_e$ based on $r^2$ corrected by genomics relationship structure can be rationalized using current knowledge of the history of the dairy cattle breeds producing milk in Korea.