• Korean Journal of Poultry Science
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• v.37 no.1
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• pp.81-87
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• 2010

To estimate the genetic characteristics and cumulative power of discrimination (CPD) Korean Native Chicken. We used a total of 195 genomic DNAs from four breeds population (Korean Native Red chicken: R, Korean Native Yellow chicken: Y, Korean Native Black chicken: L, Ogal chicken: S). Frequencies of microsatellites markers were used to estimate heterozygosities and genetic distances. The lowest distance (0.05) was observed between the R and L strains and the highest distance (0.158) between the L and S strains. Korean native chicken strains (R, Y, K) have each other comparatively near genetic distance. Cumulative power of discriminate (CPD) was 99.999% by including the 10 microsatellites loci individual identification system. And then matching probability in that two different individuals incidentally have same genotype was estimated to $0.36{\times}10^{-7}$. The system employing the 10 markers therefore provided to be applicable to individual identification in Korea native chicken.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.27-62
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• 1975

These studies were aimed at clarifying whether or not selecting agronomic characteristics of hybrid-rice populations under greenhouse conditions was useful. The selection of two quantitative characteristics, culm length and heading date, and two qualitative characteristics, shattering and awnedness, was very effective, but the flag leaf length and the exsertion of panicle was not consistent, varying from one cross to another.

• Journal of Life Science
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• v.18 no.6
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• pp.770-775
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• 2008

Several studies reported quantitative trait loci (QTL) for meat quality on porcine chromosome 2. For application of the chromosomal information to pig industry through using DNA technology, single nucleotide polymorphism (SNP) markers are developed by comparative re-sequencing of polymerase chain reaction (PCR) products of 13 candidate genes. A total of 34 SNPs were identified in 11 PCR products, an average of one SNP in every 296 bp.PCR restriction fragment length polymorphism (RFLP) assays were developed for 11 SNPs and used to genotype four commercial pig populations in Korea. The SNP markers were used to map candidate genes in QTL and to clarify the relevance of SNP and quantitative traits.

• Journal of Aquaculture
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• v.20 no.1
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• pp.47-50
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• 2007

The primordial germ cells of the oblong rockfish, Sebastes oblongus were buried under fibrous mesenchymal tissues between gut and mesonephric duct of pre-larva with 4.0 mm total length (TL) at 1 day after the parturition. In the juvenile of 22.0 mm TL at 71 days after the parturition, the gonad composed of a large number of gonial cell and formed of cavity along the lateral side of the gonad, differentiated to the ovary. At this time, the gonad formed seminiferous tubules by somatic cells, was differentiated to the testis. The smallest oblong rockfish that possessed primary oocytes was about 42.1 mm TL at 141 days. Spermatogonia remained quiescent until most fish were over 42.1 mm TL at 141 days. The oblong rockfish the differentiated directly into male or female without an intermediate female phase at the early indifferentiated stage. Therefore, the oblong rockfish belongs to the differentiated type of gonochoristic teleosts.

• Journal of Life Science
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• v.30 no.11
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• pp.1007-1011
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• 2020

This study was conducted to analyze the genetic diversity and relationships that discriminate between Korean native black goat populations (Dangjin, Jangsu, Tongyoung, and Gyeongsang National University strains) and crossbred goats. Monomorphic single nucleotide polymorphisms (SNPs) in each strain were collected, and 133 common SNPs were selected for analysis. These 133 monomorphic SNPs showed differences in the genetic structure of the Korean native black goat and crossbred goats, and results from the principal component analysis (PCA) showed that the two can be clearly separated. Furthermore, analysis of the validation population comprising 70 individuals (Korean native black goats, n = 24; crossbred goats, n = 46) with the reference population showed that Korean native black goat strains and the reference population have the same genetic structure, and the crossbred goats shared only part of the genetic structure with the reference population. The result of the PCA analysis showed that the Korean native black goat strains form one population, whereas the foreign strains form another population which is more widely dispersed than the Korean native black goat strains. Thus, the results from this study can be used as baseline data for the conservation of genetic resources of Korean native black goat communities through utilization of monomorphic SNPs and for the introduction of exotic species for further improvement in genetic diversity. This study can also help reduce unnecessary inbreeding and gene flow between native strains.

• Journal of Sericultural and Entomological Science
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• no.11
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• pp.51-54
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• 1970

External features of silkworms are not evident during stage of larvae and pupae like in the stage of imagines. In general, therefore, sexing of larvae has been depended on Herold's gland of males or Ishiwata' sexual spots (Anterior sexual spots and posterior sexual spots) of a female 2-3 days after of the 5th age since it is relatively easy to classify in this period. Sometimes. however, we made mistake of sexing since a pair of small spot around the abdomen of 9th abdominal of males and posterior sexual spot of females was found at the same position. This study has been conducted in order to obtain essential points of classifing the above it will be summarized as follows: A. Existence of the males small spots on 9th abdominal segment were varied by races. Through observation races by races the more larvae which had the small spots were found in chinese races than the Japanese, and 57 percent of the Chinese orgin larvae of the small spot were picked among total counted males. B. The small spots were more or less roundly shaped just as posterior sexual spots of females, and these spots were colored slightly even the colors were somewhat different by races. Milky color was seen in the case of the posterior sexual spots. The small spots were observed smaller than the posterior sexual spots. It is difficult classify the sexual spots during stage of mature larvae, but it was easily classified small spots by the naked eye even in the same stage. The small spots were found at the same site of the posterior sexual spots. C. After sexing by based on the small spots and Herold's gland, the sexing through purpae bodies were carried out again to confirm its correctness. Average 5. 2 percent of more opposite sex were found in the latter. This figures supposed to be caused the location of the small spots coincide with the posterior sexual spots. D. The moths, no disorder were found in daily activities and their generative functions depend on the existence of the small spot and thickness of its color. E. It is presumed that existence of the small spots were caused by races, heredity nature, voltinism, moulting, and etc.

• Journal of Korean Society of Forest Science
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• v.22 no.1
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• pp.49-62
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• 1974

1. In the comparison of survival ratio among three different methods(bark graft, veneer graft, root graft), bark graft showed the highest survival ratio and root graft was the lowest. It was shown to be significant at the level of 5% in the analysis of variance for the results. It was able to be supposed that one of the main causes for the results was the different amounts of ferric tannic acid which was formated owing to the reaction of grafting knife with tannic acid oozing from cutting faces of the tree. In juvenile tissue graft, the survival ratio of inverted radicle graft was a little higher than that of juvenile stem graft, but there was no significant difference between two methods in analysis of variance. 2. The most hairs of chestnut tree leaves were recognized as stellates on the most part of leaves except for venation. The number of rays in the stellates was ranged from 4 to 8 generally. It was shown to be highly significant differences at the level of 1% among the each race growing at the similar environmental condition in the length of ray and the distributed ratio of the stellates having different ray number. 3. Excepting for the basal width of serration there were no significant differences between $Imakita_1$, $Imakita_2$ as well as between $Teteuchi_1$, $Teteuchi_2$ at the each point of experimental items in this study. Such results made this study more useful. 4. Among the races that were growing in the similar environmental condition, there were highly significant differences at the level of 1% in the length and the width of serration. 5. The rolling of hair, the angle of serration from the leaf margin, the existence of lateral vein in the serration, the intrusion of main vein into the serration and the width of main vein were observed to be somewhat useful as the subsidiary methods for the identification of chestnut races.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.359-364
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• 2005

Comparison of pesticide residue dissipation in/on cucurbitaceous fruit vegetables applied by foliar spraying under greenhouse was carried out to give information on crop grouping for assessment of pesticide risk. Even though the initial deposit of spayed pesticide on the target vegetables were somewhat different from the varieties, the dissipation patterns of the residues gave a similar tendency. In case sub-groupings of cucurbitaceous fruit vegetables are carefully arranged, the residue data among the vegetables are able to be taken for pre-harvest interval (PHI) settings or food safety assessment.

• Korean Journal of Pharmacognosy
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• v.52 no.2
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• pp.69-76
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• 2021

Cannabis sativa is an important industrial plant utilized to produce fiber, oil, and medicinal ingredients. A chemotype of cannabis is divided into "Drug type" with predominance of tetrahydrocannabinolic acid (THCA) and "Fiber type" with cannabidiolic acid (CBDA). To develop molecular markers for the discrimination of these two types, nucleotide sequences of THCA synthase and CBDA synthase as well as their pseudogenes were retrieved from the recently published cannabis genome in chromosome scale. Gene-specific SNPs were discovered by multiple alignment of these sequences, and 2 dominant marker sets from each gene were designed for selective amplification. Our markers successfully identified "Drug type" and "Fiber type" cannabis plants as well as forensic samples including processed materials. Our molecular markers will provide a fast and efficient system for molecular-based identification of the cannabis plant.

• Korean Journal of Poultry Science
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• v.42 no.1
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• pp.1-8
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• 2015

Recently, duck meat consumption has been rapidly increased because consumers recognized duck meat for healthy food. In relation to this, Korean duck industry need to develop Korean native duck (KND) breed for both conservation perspective and self-sufficient of the breeding stocks. In this study, 24 microsatellite (MS) markers were investigated for classification of KND and commercial duck (CD) breeds in the Korean market. Using these MS markers, the calculated number of alleles (K), expected heterozygosity (He) values and polymorphic information contents (PIC) were 1~16, 0~0.865 and 0~0.841, respectively. Also, the expected probability of identical values in random individuals (PI), random sib ($PI_{sib}$) and random half-sib ($PI_{half-sib}$) were estimated as $1.64{\times}10^{-16}$, $2.60{\times}10^{-7}$ and $1.30{\times}10^{-12}$, respectively. The results indicated that the expected probabilities of identity powers were enough for the individual identification. However, KND and CD breeds were not fully discriminated well using the 24 MS markers, which may CD and KND has shared same origin or crossbred. Therefore, further studies will be ultimately needed for developing a genetically pure line of KND breed even though the DNA markers used. Finally, these results will provide useful information for individual traceability system in ducks.