• Journal of Korean Society of Forest Science
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• v.77 no.3
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• pp.338-350
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• 1988

In order to solve the taxonomic problems of the genus Juniperus growing in South Korea, an identification key of the genus and species was developed bayed un flower structure, cane and seed shape, branching habit, tree form, leaf characteristics etc. of the 7 native species and the a exotic cultivars. The typical pattern of karyotype found by chromosome analysis of the species was used for the identification among morphologically similar species. The length of chromosome were ranged $9{\sim}15{\mu}m$ in all studied specie. J. chinensis, var. procumbens, and var. kaizuka sere tetraploid, 4n=44, var. globosa, var. procumbens, var. horizontalis, J. virginiada, J. rigida, J. rigida var. longicarpa, and J. coreana were diploid, 2n=22. The species in the Sabina section showed large variation in the length of chromosome and kinetochore position. The species in the Oxycedrus section showed the cytological characteristics that the 11th chromosome t-type(acrocentric), and the m-type abundant chromosome set was relatively uniform as compared to those of the Sabina section. The species in the Sabina section, which are planted in the large city area, show great morphological variation because many different ecotypes were mixed and often crossed among them. In summary, this study was able to make clear identification and to find out similarity among Juniperus, species by the morphological and cytological analysis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.191-197
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• 1984

This study was conducted to investigate the flowering habit for the botanical types of peanut (Arachis hypogaea. L) in cultural limiting region. Eight peanut varieties pertaining to virginia, Spanish, Valencia, Shinpung type were used in this study. Shinpung type, a new erect type was developed at Crop Experiment Station, ORD. Appearance of the first flower of peanut plants is observed at a relatively early growing stage. Number of days to first flower were 41 days under vinyl-mulching while non-mulching culture took 55 days. Number of days to first flower were delayed in order of Valencia, Spanish, Shinpung, Virginia type. Flowering durations were distinguished among botanical types and days of those were Virginia 85-93, Spanish 101-105, Valencia 106-113, Shinpung 82-88 days, respectively. The Spanish and Valencia types produced more flowers than Virginia and Shinpung types. The maximum flowering stage of Shinpung and Virginia types reached early and ceased by one cycle, while Spanish and Valencia types came late and showed maximum stage through the early and late stage during the growth stage. By vinyl-mulching, the maximum flowering stage was shortened by 20 days than that of non-mulching. Distribution of flowers for each of branch positions to total flowers occupied 52-53% in two cotyledonary branchs, 23-27% in 3rd to 5th branchs, 20-25% in over. 6th branchs. Shinpung type was considered more favorable botanical type than the other types for the breeding of early maturing high yielding variety because of shortening of days to first flower, flowering duration and distribution of lower branch of effective flowers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.2
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• pp.190-196
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• 2015

We evaluated the morphological characteristics in 100 super sweet corn inbred lines, which were developed to breeding super sweet corn variety at Gyeongsangbuk-do Agricultural Research and Extension Services, by examining six quantitative and two qualitative characteristics. On the result of evaluation of two qualitative traits, most of inbred lines showed yellow (91 inbred lines) at seed color (QL1) and weak (68 inbred lines) at seedling vigor (QL2). In the survey of six quantitative traits, the average value for each trait indicated as follows: days of tasseling (QN1, 41.0 to 55.0 days), days of silking (QN2, 44.0 to 59.0 days), anthesis-silking interval (QN3, 2.0 to 7.0 days), tillering (QN4, 0.0 to 2.0), plant height (QN5, 96.0 to 187.0 cm) and ear height (QN6, 30.0 to 86.0 cm). In PCAs (principal component analysis) for 8 morphological characteristics, seedling vigor (QL2) and tillering (QN4) greatly contributed in negative direction and the days of tasseling (QN1) and days of silking (QN2) greatly contributed in positive direction on the first principal component. While, ear height (QN6) and plant height (QN5) contributed in positive direction on the second principal component. Thus these morphological traits, which were greatly contributed in the first and second principal components, might be considered to be useful for discrimination in 100 super sweet corn inbred lines. In our study, the results of morphological variation and PCAs for 100 super sweet corn inbred lines will be helpful for super sweet corn breeding programs such activities as planning crosses for hybrid and line development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.3
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• pp.312-318
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• 2014

We evaluated the morphological characteristics of 156 maize inbred lines, which were developed to breeding normal maize variety at Maize Experiment Station, Gangwon Agricultural Research and Extension Services, by examining 11 quantitative and three qualitative characteristics. On the evaluation of three qualitative traits for 156 maize inbred lines, most inbred lines showed yellow (85 and 84 inbred lines) at tassel color (QL1) and silk color (QL2), and showed semi erect (105 inbred lines) at plant type (QL3). While, the evaluation of 11 quantitative traits for 156 maize inbred lines, they showed the morphological variation in days of tasseling (QN1, 56.5 to 76.0 days), days of silking (QN2, 59.0 to 85.5 days), stem thickness (QN3, 12.7 to 42.9 mm), plant height (QN4, 111.8 to 239.8 cm), ear height (QN5, 48.2 to 126.5 cm), 100 kernel weight (QN6, 14.9 to 36.4 g), ear length (QN7, 10.0 to 79.0 cm), setted kernel length (QN8, 8.0 to 70.5 cm), ear thickness (QN9, 4.0 to 22.0 cm), total kernel weight (QN10, 22.0 to 490.0 kg) and water content (QN11, 9.3 to 11.9%), respectively. As a result, 11 inbred lines (00hf3, 00hf19, 00hf30, 00hf36, 02S8069, 02S8072, 02S8090, 02S8099, 05S10011, 06S8085-6, 07S8011) in the 156 normal maize inbred lines have showed comparatively high values. While, the results of PCA (principal component analysis) indicated that the ear length (QN7), setted kernel length (QN8), ear thickness (QN9) and total kernel weight (QN10) greatly contributed in positive direction on the first principal components. And also, days of tasseling (QN1), days of silking (QN2), plant height (QN4) and ear height (QN5) contributed in negative direction on the second principal component. Thus these morphological characters, which were greatly contributed in the first and second principal components, might be considered to be useful for discrimination among 156 normal inbred lines. Specifically, this study's assessment of morphological characteristics of 156 normal inbred lines will be helpful useful for normal maize breeding programs such activities as planning crosses for hybrid and line development at Maize Experiment Station, Gangwon Agricultural Research and Extension Services.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.29-34
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• 2011

Using the materials collected from nine farms in a three-way cross system to produce commercial pigs produced from F1 sows (Landrace $\times$ Large White) $\times$ Duroc, the power of individual discrimination and parentage of the 13 microsatellite (MS) marker set that has been suggested for individual/brand identification (traceability) was empirically tested. Initially, genotypes of the parental population ($F_1$ sows and Duroc), and commercial pigs were determined and the genotype frequency and polymorphic index were estimated using the Cervus 2.0 program. The probability of identity among genotypes of random individuals, that random half sibs and that of full sib individuals, based on the genotypes from 91 $F_1$ sows and Duroc were expected to be $4.94{\times}10^{-34}$, $8.16{\times}10^{-23}$ and $2.01{\times}10^{-08}$, respectively, using the API-CALC version 1.0 program. When commercial pigs were included, the estimates increased to $3.74{\times}10^{-35}$, $5.48{\times}10^{-25}$ and $2.96{\times}10^{-11}$, respectively. For the empirical verification of the estimated powers of individual discrimination and parentage, the parentage test was performed for 452 commercial pigs using PAPA version 2.0, and individuals with the same genotype were investigated using the Cervus version 2.0 program. Parents for all commercial pigs were successfully estimated and no identical individual was identified in the pedigree. Although the individual discriminating power was not fully verified because of the lack of individuals corresponding with the theoretical power, the 100% efficiency of parentage test was clearly confirmed. Therefore, we believe that the 13 MS marker set in conjunction with management record/information for the pig production kept in a farm/brand should be useful in the pork traceability in a brand unit.

• Journal of Life Science
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• v.25 no.6
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• pp.624-630
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• 2015

This study examined the genetic distance among Chikso (Korea native brindle cattle) in nine regional areas using allele frequencies and a genetic diversity analysis with microsatellite markers. The analysis of the genetic diversity and genetic relationships of 2068 Chikso (383 KW, 180 GG, 52 KN, 129 KB, 332 UL, 24 JN, 198 JB, 148 CN, 622 CB) was carried out using 11 microsatellite markers. The number of alleles, observed heterozygostiy (H_obs), expected heterozygosity (H_exp), and polymorphism information content (PIC) of the 11 microsatellite markers were 8–24, 0.672–0.834, 0.687–0.886, and 0.638–0.876, respectively. The expected probability of identity values in random individuals (PI), random half-sib (PI_half-sibs), and random sibs (PI_sibs) were estimated to be 5.24×10⁻¹⁹, 2.63×10⁻⁰⁶, and 2.63× 10⁻⁰⁶, respectively, indicating that these markers can be used for traceability systems in Chikso cattle. The results of a phylogenetic tree (neighbor-joining tree), principle component analysis (PCA), and factorial component analysis (FCA) revealed genetic distance among nine Chikso populations. In conclusion, this study provides useful basic data that can be utilized in Chikso breeding and development. In addition, we will have to manage and conserve as a valuable genetic resource, without losing diversity of Chikso.

• Journal of Sericultural and Entomological Science
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• v.14 no.2
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• pp.81-92
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• 1972

Studies on Pathogenicity of Nosema bombycis Naegeli are summarized as follows: 1. The mortality of the parents, Jam 103 and Jam 104, is remarkbly higher than that of the hybrid, Jam 103$\times$Jam 104, whereas there is no difference in the mortality between the parents. 3. In the mortality of the pathogen-concentration, it is increased in order of the following concentrations inoculated, 10$^{8}$ , 10$^{7}$ , 10$^{8}$ and 10$^{5}$ /ml. 3. In the mortality of each instar, it is high in order of 5th, 4th, 3rd, and 2nd instar. 4. In the interaction between the mortalities of the varieties and the concentrations, 1) The mortality shows no differences between the parents and the hybrid in the high concentration of 10$^{8}$ /ml. 2) The mortality of the hybrid is lower than that of the parents in the low concentration of 10$^{5}$ /ml, whereas no difference is found between the parents. 3) The interaction appears at the same level in the middle concentration of 10$^{6}$ /ml to the parents and of 10$^{7}$ /ml to the hybrid. 5. It was pointed out that active immunity depends upon the volume of antigen injection, immunizing period, and injection intervals. In this experiment, it is noticed that the optimum volume of injection is above 20ml and D is the best one of the four treatment (A.B.C.D.). 6. The immune sera indicate such a 12,800 high titer in the indirect method can be obtained from the D immunizing method. Silkworm tissues and N. bombycis spores show self-fluorescence, but it is able to distinguish it from the F.I.T.C. by using the U.V. filter. 7. The midgut epithelium is examined to be the first site of the tissues which are penetrated into and multiplied by the inoculation of the pathogen per os.

• Horticultural Science & Technology
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• v.32 no.1
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• pp.105-114
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• 2014

We established a high throughput screening system of African yam tuber lines which contain high contents of total carotenoids, flavonoids, and phenolic compounds using ultraviolet-visible (UV-VIS) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy in combination with multivariate analysis. The total carotenoids contents from 62 African yam tubers varied from 0.01 to $0.91{\mu}g{\cdot}g^{-1}$ dry weight (wt). The total flavonoids and phenolic compounds also varied from 12.9 to $229{\mu}g{\cdot}g^{-1}$ and from 0.29 to $5.2mg{\cdot}g^{-1}$dry wt. FT-IR spectra confirmed typical spectral differences between the frequency regions of 1,700-1,500, 1,500-1,300 and $1,100-950cm^{-1}$, respectively. These spectral regions were reflecting the quantitative and qualitative variations of amide I, II from amino acids and proteins ($1,700-1,500cm^{-1}$), phosphodiester groups from nucleic acid and phospholipid ($1,500-1,300cm^{-1}$) and carbohydrate compounds ($1,100-950cm^{-1}$). Principal component analysis (PCA) and subsequent partial least square-discriminant analysis (PLS-DA) were able to discriminate the 62 African yam tuber lines into three separate clusters corresponding to their taxonomic relationship. The quantitative prediction modeling of total carotenoids, flavonoids, and phenolic compounds from African yam tuber lines were established using partial least square regression algorithm from FT-IR spectra. The regression coefficients ($R^2$) between predicted values and estimated values of total carotenoids, flavonoids and phenolic compounds were 0.83, 0.86, and 0.72, respectively. These results showed that quantitative predictions of total carotenoids, flavonoids, and phenolic compounds were possible from FT-IR spectra of African yam tuber lines with higher accuracy. Therefore we suggested that quantitative prediction system established in this study could be applied as a rapid selection tool for high yielding African yam lines.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.684-696
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• 1995

A mutant for chalky endosperm and genetic male sterility (GMS) was newly developed in rice. The two characters were found to be controlled by single recessive gene which has pleiotropic effect, indicating that chalky seeds should be GMS seeds in segregating populations. Chalky seeds showed the same shape and size as normal seeds. However, starch composition of central part of endosperm was looser and shape of starch granules was rounder compared with normal endosperm, resulting in significantly lower grain weight, absolute density and grain hardness in chalky grains than in normal ones. Amylose content and gel consistency of chalky grains were much lower and harder, respectively. Male sterile plants showed much shorter plant height, poorer panicle exsertion and lesser panicle number compared with normal plants. Microspore abortion stage in pollen developmental process was observed as before meiosis. Male sterility of the mutant was stable regadless of temperature and day length. A system breeding hybrid rice using this mutant was discussed, comp ring with other systems utilizing cytoplasmic-genic male sterility(CGMS) and environment sensitive GMS(EGMS). Separation of GMS seeds in mixed seed bulks by specific gravity (1.14∼1.16g / cm3) was successful about 85∼90%. But some mixed normal plants were seemed to be easily removed by the apparent difference in growth characters at seedling stage. The highest natural outcrossing rate of this GMS line was as 17.3 % in a plot treated with 2-row pollinator, I-row GMS, and GA3 + cutting of flag leaf + pollen-scattering by rope.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.30-43
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• 1981

On unwedded paddy fields, six cropping patterns of rice cultivation, namely direct broadcast seeding, direct row seeding, machine transplanting, early season hand transplanting, standard season hand transplanting, and late season hand transplanting, were detected with two representative rice cultivars (Milyang 23 and Sadominori) to estimate the comparative fluctuation patterns of weed flora. As a result, number of emerged weed species, most crowding stages, differences of weed growth among cropping patterns, possible tendencies of competition in plant heights among plant groups, variations in Importance Values, and Simpson's Index analysis were discussed, respectively.