• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.135-142
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• 2024

Clover cyst nematode (Heterodera trifolii, CCN) is one of the important plantparasitic nematodes in the Republic of Korea, causing serious damage to Kimchi-cabbage in Gangwon province since 2017. Soil fumigants are the preferred choice for managing CCN. However, cabbage fields in Gangwon province have a slope, making it challenging to apply soil fumigants and use plastic mulch. Consequently, alternative materials should be developed for managing CCN. Nematicidal cover crops and resistant cultivars are among the alternatives. We conducted resistance screening of 82 white mustard(Sinapis alba) resources from a genebank at RDA against CCN for use as nematicidal cover crops or breeding materials. In the first assay (1st, 2nd, and 3rd pot experiments), 15 white mustard resources were selected, while others were susceptible to CCN. To confirm the reproducibility of resistance to CCN for 13 selected resources, the second assay was performed. As a result, five white mustard resource (IT297309, IT297312, IT302951, IT302953, IT302954) demonstrated resistance to CCN. These findings indicate the potential use of these five white mustard resources as nematicidal cover crops or for breeding cultivars of Kimchi-cabbage in Republic of Korea.

• Journal of the Korean Society for Marine Environment & Energy
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• v.18 no.1
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• pp.45-49
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• 2015

Disturbance to marine wildlife is a serious negative impact of marine debris. In this study, the percentages of Black-faced Spoonbill nests that included plastic marine debris were calculated from surveys conducted on an islet named Suhaam off the western coast of South Korea. The percentages of nests including plastic decreased from 71% in 2010 to 37% in 2011 to 33% in 2012. The total number of nests increased from 28 in 2010 to 38 in 2011 to 43 in 2012. These differences in nests and nesting materials were possibly due to natural nesting materials such as tree branches and rice straws that were provided at the breeding site as a protective action in 2011 and 2012. Additional conservation efforts should be made to prevent further negative impacts from marine debris.

• Journal of the Korean Ceramic Society
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• v.52 no.1
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• pp.33-40
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• 2015

Onggi, described as a 'breathing' type of pottery' has significantly influenced the traditional food culture of Korea. It is known that Onggi is an optimal type of storage for fermented foods such as soy sauce, salted seafood, and Kimchi, as air or liquid can penetrate through the body of this material. These foods gain flavor due to the breeding of aerobic bacteria at the beginning of the fermentation process. In this study, Onggi materials from five regions, Gangjin, Yeoju, Ulsan, Yesan, and Jeju, were collected and analyzed to determine their chemical and physical properties before and after sintering. The differences in the raw materials of other mining regions are examined in terms of their chemical and mineralogical compositions, specific surface area, particle size, and particle distribution. Among them, the Gangjin raw material has the greatest mean particle size of $92.29{\mu}m$, as well as the widest particle size distribution. Differences in the levels of $SiO_2$ and $Fe_2O_3$ are shown among Onggi raw materials. However, the crystalline phases formed after sintering are identical, except for the Jeju samples. At all sintering temperatures tested here, Gangjin Onggi showed the greatest porosity, leading to complete air permeation through the body within 90 minutes. These results taken together indicate that air permeation is strongly related to the pore structures in the Onggi body. This is assumed to affect the fermentation behavior.

• Korean Journal of Agricultural Science
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• v.7 no.1
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• pp.12-26
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• 1980

A new, improved maize varieties are greatly needed to meet the national demand for the maize, and a new germplasm should be investigated to supply necessary breeding materials for the required maize breeding. The Korean local maize lines, which has never been wholly studied for the purpose of breeding should be enough to supply such breeding materials at least in Korea. The objectives of this study were to maintain useful Korean local lines, to investigate good plant characters and to analyze the Korean local maize lines in the respect of genetic make-up. A total of 820 lines and 200 lines were used for the present study. Lines to maintain were planted at experimental farm of the Crop Experiment Station, Office of Rural Development, Suwon and the lines to study genetic make-up were planted in Dae-jon. The summarized results are as follows : 1. A total of 1200 lines from 820 collections were sibbed for future use. 2. Two hundred collection were sibbed, selfed and testcrossed for genetic study in 1980. 3. Ten lines were surely confirmed as resistant lines to virus disease epidemic in most introduced maize varieties. 4. A dozen Lines were having three to four ears per plant. 5. Five lines were showing three to four tillers per plant. 6. One of the most significant and important finding through the study was to obtain the lines with three to four tillers bearing all together eight to nine ears. The lines of multi-ears and multi-tillers must have great breeding potential for the future use. 7. A great variation was observed in the tasselling days, 100 kernel weight and protein content. 8. From the genetic study of local maize lines for plant height and 100 kernel weight, the following findings were obtained. a. On the average six percent of inbreeding depression expressed in percent decrease over sibbed counterpart were found for the plant height. b. Fourty percent of heterosis expressed in percent increase over sibbed counterpart were observed in the plant height. c. The homogeneity or degree of homozygosity calculated from heterosis minus inbreeding depression was on the average 34 percent for plant height. d. The average inbreeding depression expressed in percent decrease over sibbed counterpart was 15 percent for 100 kernel weight. e. The average heterosis expressed in percent increase over sibbed counterpart was 43 percent for 100 kernel weight. f. The degree of homozygosity calculated from the heterosis minus inbreeding depression was 28 percent for 100 kernel weight.

• Journal of Animal Science and Technology
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• v.53 no.5
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• pp.397-408
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• 2011

The study was carried to identify the impact on nation-wide genetic evaluation and to obtain basic materials for the development of strategies in Swine Improvement Network Project (SINP). Data consisted of pedigree records of 235,511 and performance records of 70,747 for Duroc from 1987 to 2010 were collected by Korea Animal Improvement Association. Performance traits included three point back fat thickness (Shoulder, Belly, Waist), loin area, days to 90 kg and average daily gain. Exchange of genetic resources cross the breeding farms was not high, and furthermore the sizable farms which can accommodate genetic evaluation within the farm were scarce. Three data sets (individual farm evaluation: I, two sub-group evaluation: S, and whole eight farm evaluation: P) were used for genetic analysis. Genetic variances were larger in subordinate farms than in joiners farms for connectedness, and consequently the heritabilities were generally higher in subordinate farms than in joiner farms with I. The standard errors of heritability were small in the order of I, S and P. Estimated average inbreeding coefficients were 1.12%, 0.95% and 1.53% for joiner and subordinate group with S and population with P, respectively. The estimated correlations of breeding values with I and P were lowest. The correlations of breeding values with I and P for traits ranged 0.22 to 0.45 for moved parent animals and 0.24 to 0.72 for all animals. The results in the study suggest that nation-wide evaluation uses more pedigree information and improves accuracy. Furthermore SINP for connectedness could help to improve the accuracy of evaluation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.6
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• pp.139-151
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• 2007

To protect the surface of ground-cutting slopes and ground-raised slopes and to recover environment-friendly slopes at the national road expansion construction between Gamchon and Yaechon, test-construction work was done using several modes of hydro-seeding measures to select a suitable construction method through the field survey; the results were as follows : As a result of survey on physio-chemical characteristics of soil, the average soil inclination on ground-raised slopes was from 4.73 mm to 5.37 mm; the average soil acidity was from pH 6.47 to 6.73; the average soil humidity was within the scope of 0.57~1.70 %,; the average soil inclination on ground-cutting slopes was 9.17~10.43mm; the average soil acidity was pH 6.67~6.77 and the average soil humidity was within the scope of 0.53~1.27 %; considered overall, they showed generally satisfactory base materials for plant breeding. As a result of the number of sprouting individuals, the average sprouting number of individuals on test spots executed by Coir net with Seed spray construction methods and the average number of sprouting individuals on other test spots executed by furrow-digging with Seed spray and Straw mat-mulching measures were 1,172 number of per square meter and 970 number of per square meter respectively; thus they showed higher numerical value comparing with other test spots. Likewise, the average number of sprouting individuals on test spots of the ground-cutting slopes executed by Coir net with Seed spray method and the average number of sprouting individuals on other test spot executed by furrow-digger with Seed spray and Straw mat-mulching measures were found to be 1,107 number of per square meter and 1,105 number of per square meter respectively, whose numerical value showed rather higher other test spots. As a result of a survey on living plants' breeding index [dried weight], the weight in dried state on test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures on both ground-raised and ground-cutting slopes was found to be higher and showed similar characteristics statistically. As a result of survey on the surface-covering degree of ground-raised slopes, nine weeks after test construction, test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures showed commonly more than 70% of surface-covering degree, but other test spots showed only below 35% of surface covering degree; especially in case of test spots by Verdvol seed spray measures, they showed 10% of the lowest surface-covering. Surface-covering degree on the test spot of ground-cutting slopes nine weeks after test construction showed more than 75% both executed by Coir net with Seed spray construction method and executed by furrow-digger with Seed spray and Straw mat-mulching measures. As a result of survey on appearing plants on the test spots, there dominates Eragrostis curvula both on ground-raised slopes and on ground-cutting slopes with other seeding plant life's lower breeding and there appear intruders, such as Setaria viridis Beauv, Digitaria sanguinalis Scop, and Chenopodium album var.centrorubrum Makino. As for water-borne excavation and soil's washing-away on the slopes, there happened less washing-away and water-borne excavation with good breeding of plant life on test spots executed both by Coir net with Seed spray construction method and by furrow-digger with Seed spray and Straw mat-mulching measures, but there happened much more soil's washing-away along with water-home excavation at the test spot executed by Seed spray with measures. After the research results of test construction sites are examined overall, it's presumed that furrow-digger with Seed spray and Straw mat-mulching measures [interval between lines is 40cm, 5cm in depth] will be preferred to prevent erosion and water-home excavation of slopes located within the construction sites.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.3
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• pp.1-10
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• 2020

The purpose of this study is to identify whether the cranes had been bred in the palace of the Joseon Dynasty period and to consider the related cases. The temporal range of this study is in the Joseon Dynasty period, and the spatial range is throughout the entire palace, including the naejeon(內殿) and oijeon(外殿), and government offices inside(闕內各司) and government offices outside(闕外各司). The reference materials for this study were partly extracted and translated from the original documents to consider, and a Korean version of documents was used in the database of the Institute for the Translation of Korean Classics. The results of this study are summarized as follows. First, the cranes were bred from the early Joseon Dynasty Era in Uijeongbu, the highest government office in the Joseon Dynasty period. After the Japanese Invasion of Korea in 1592, crane breeding in Uijeongbu(議政府) seems to have been suspended due to the damage to the government building and the change in the status of the government office. Second, crane breeding in Hongmungwan(弘文館), which was responsible for the classics colloquium(經筵) and public opinions and assisted the king by the side, continued from the early Joseon Dynasty period(Jungjong's Era) to the late Joseon Dynasty period(Jeongjo's Era) after the Japanese Invasion of Korea in 1592. Third, in the Jeongjo's Era, the cranes were also bred in Gyujanggak(奎章閣), which was newly established as the central institution of learning to strengthen the royal authority. At that time, it seems that several cranes were bred in Gyujanggak. Fourth, it is judged that 'Crane breeding' in the core government offices of Joseon, such as Uijeongbu, Hongmungwan, and Gyujanggak, was meaningful as a symbol of identities, such as the status and character of the institution. Fifth, it seems that the cranes bred in the palace, including Hongmungwan, were conventionally brought by the Baecheon County of Hwanghae-do. This convention caused minor conflicts between the central and local government offices during the Yeongjo's Era, but it seems to have continued throughout the Jeongjo's Era. In this study, there is a limit that most of the studies were conducted based on local data. If further data discovery and translation outcomes are accumulated in the future, more abundant cases will be identified. The deepened follow-up studies are also needed, other than the cases of rearing cranes in the local government offices and temples.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.2
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• pp.120-129
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• 2021

Securing a range of wheat resources is of particular importance with respect to wheat breeding, as it provides a broad genetic foundation. Although wheat breeders have used different wheat germplasms as material resources in current breeding systems, the traits of most germplasms collected from foreign countries differ from the unique traits that have evolved in the Korean environment. In this study, conducted over a 2-year period (2018 and 2019), we therefore evaluated the agricultural traits 1,967 wheat germplasms collected not only in Korea but also worldwide. During the period from sowing to February, the average temperature in 2019 was greater than 1℃, whereas from March to June, the average temperature was approximately 0.9℃ higher in 2018. Compared with the growth recorded in 2018, the stem length in 2019 increased by approximately 20 cm in 2019, and there were notable differences heading date and maturation between 2018 and 2019. In 2019, the heading dates of 973 and 713 wheat resources were earlier and later than those in 2018, respectively. Moreover, stem length was found to be highly correlated with the heading date and maturation. In Korea, where the rainy season and tine of rice transplantation overlap with the time of wheat harvest, early flowering time with high grain yield has been the most important selection target with respect to wheat breeding. We anticipate that the findings of this study will provide would use a foundation for the selection of elite materials and the development of resource core-sets for Korean wheat breeding programs.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.191-204
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• 1994

Due to its topographic complexities and various climatical condition, Korea exhibits diverse forest types. Dominant tree species in this zone are Quercus spp., Betula spp., Zelkova spp., Fraxinus spp., Pinus densiflora, Pinus koraiensis, and Pinus thunbergii ete. Genetic conservation in forest species in Korea there are three ways ; one is in situ, other is ex situ and third is in-facility conservation. In situ conservation include that are the present status of conservation of rare and endangered flora and ecosystem, the reserved forest, the national and provincial park, and the gene pool of natural forests. Ex situ conservation means to be established the new forest from in situ forest stands, progeny and provenance test populations, seed orchard and clone banks, and gene conservation in-facility. As a tool for low temperature storage, several aspects on in vitro system were studied ; (1) establishment of in vitro cultures from juvenile and/or rejuvenated tissues, (2) induction of multiple shoots from the individual micropropagules, (3) elongation of the proliferated shoots. Studies on cold storage for short-and long-term maintenance of in vitro cultures under $4^{\circ}C$ in the refrigerator were conducted. For the cryopreservation at $-196^{\circ}C$, various factors affecting survivability of the plant materials are being examined. The necessity of gene conservation of forest trees is enlarged not only to increase the adaptability for various environments but also to gain the breeding materials in the future. For effective gene conservation of forest trees, I would like to suggest followings ; 1. Forest stands reserved for other than the gene conservation purposes such as national parks should be investigated by botanical and gene-ecological studies for selecting bio-diversity and gene conservation stands. 2. Reserved forest for gene pool should be extented both economically important tree spp. and non-economical species. 3. Reserved forest for progeny test and clone bank should be systematically investigated for the use of Ex situ forest gene conservation. 4. We have to find out a new methodology of genetic analysis determining the proper and effective size of subpopulation for in situ gene conservation. 5. We should develop a new tree breeding systems for successful gene conservation and utilization of the genetic resources. 6. New method of in-facility gene conservation using advanced genetic engineering should be developed to save time and economic resources. 7. For the conservation of species with short-life span of seed or shortage of knowledge of seed physiology, tissue culture techniques will be played a great role for gene conservation of those species. 8. It is are very useful conservation not only of genes but of genotypes which were selected already by breeding program. 9. Institutional and administrative arrangements including legistlation must be necessarily taken for gene conservation of forest trees. 10. It is national problems for conservation of forest resources which have been rapidly destroyed because of degenerating environmental condition and of inexperienced management system of bio-diversity and gene conservation. 11. In order to international cooperation for exchanging data of bio-diversity and gene conservation, we should connect to international net works as soon as possible.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.2
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• pp.89-94
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• 1998

Granule bound starch synthase (GBSS), also known as the '"waxy protein'", is responsible for the synthesis of amylose in the amyloplasts of cereal crops. In hexaploid wheat (Triticum aestivum L.), GBSS is involved in amylose synthesis and rolls as an important factor to determine flour quality and end-use quality in food products. Genes on three Wx loci have been found to encode GBSS in common wheats. We developed techniques for the purification and separation of GBSS in wheat. Three major GBSS isoforms, which were encoded by the genes on three loci, Wx-A1, Wx-B1, and Wx-D1 migrating differently by one dimensional SDS-po-lyacrylamide gel electrophoresis (1D SDS-PAGE), were identified. GBSS from 66 Korean hard and soft winter wheats were purified and determined for their Wx loci and four of them were identified possessing a null allele either at the Wx-A1 and Wx-B1 loci. With help of identification of three GBSS isoforms using 1D SDS-PAGE system, we are able to identify and monitor Wx gene expressions in breeding materials for developing waxy or partial waxy wheats without experiencing consecutive selecting generations.cting generations.