• 식물병연구
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• 제8권2호
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• pp.78-83
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• 2002

Tobacco diseases have not been recorded until 1900s in Korea, where tobacco plants were introduced at early 1700s. Practical researches on the disease have been conducted since mid 1960s. Major ten tobacco diseases were mosaic caused by tobacco mosaic virus·potato virus Y·cucumber mosaic virus, bacterial wilt, hollow stalk, wild fire caused by angular leaf spot strain, black shank, brown spot, powdery mildew and fusarium wilt. But their annual occurrences were varied according to changes of tobacco varieties and their cultivating practices. As no useful chemicals, several biological tactics have been developed to control the viral or bacterial diseases that give significant economic damages on sustainable crop yield, but not practicable to field farming condition yet. Transgenic tobacco plants containing foreign disease resistant genes have been developed by current bio-technology, but not released to farmers yet. Though some disease-resistant tobacco varieties have been developed by the conventional breeding technology and currently used by farmers, their disease controlling efficacy have been diminished by occurrence of the new strain or race. Future research on tobacco diseases has been focused on technical development to produce high quality tobacco with less production cost, which leads Korean tobacco industry to keep its competence against foreign industry and decreasing overall market.

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.718-726
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• 2010

A selected fungal strain, for production of the raw-starchdigesting enzyme by solid-state fermentation, was improved by two repeated sequential exposures to ${\gamma}$-irradiation of $Co^{60}$, ultraviolet, and four repeated treatments with Nmethyl-N'-nitrosoguanidine. The mutant strain Aspergillus sp. XN15 was chosen after a rigorous screening process, with its production of the raw-starch-digesting enzyme being twice that of usual wild varieties cultured under preoptimized conditions and in an unsupplemented medium. After 17 successive subculturings, the enzyme production of the mutant was stable. Optimal conditions for the production of the enzyme by solid-state fermentation, using wheat bran as the substrate, were accomplished for the mutant Aspergillus sp. XN15. With the optimal fermentation conditions, and a solid medium supplemented with nitrogen sources of 1% urea and 1% $NH_4NO_3$, 2.5 mM $CoSO_4$, 0.05% (v/w) Tween 80, and 1% glucose, the mutant Aspergillus sp. XN15 produced the raw-starch-digesting enzyme in quantities 19.4 times greater than a typical wild variety. Finally, XN15, through simultaneous saccharification and fermentation of a raw rice corn starch slurry, produced a high level of ethanol with $Y_{p/s}$ of 0.47 g/g.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.80-80
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• 2017

Teosinte is now known as a wild variety of corn. It is distributed in Central and South America. It is believed that teosinte contains genes for resistance to flooding because of the climate characteristics of the collected countries. Recent studies have shown that teosinte has the ability to form adventitious roots, to develop aerenchyma tissues of teosinte, and the resistance to toxic substances under flooding soil condition. Therefore, development of corn cultivars to cope with climate change and the growing corn at paddy field in Korea are required to introduce the characteristics of teosinte. However, in order to utilize teosinte resources, preconditions must be settled such as photoperiodic responsibility. Also if the preconditions are studied together with the metabolic level studies, the possibility of utilization will be even higher.

• 한국환경생태학회지
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• 제25권3호
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• pp.253-266
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• 2011

천관산의 관속식물은 89과 221속 270종 47변종 6품종의 총 323분류군으로 구성되어 있었다. 특기할 식물로는 멸종위기야생식물 II급인 히어리 1종이 분포하였고, 한국특산식물은 6과 6속 5종 1품종 총 6분류군이 생육하며, 구계학적 특정식물은 I등급 29종, II등급 2종, III등급 6종, IV등급 2종, V등급 1종으로 총 40종의 식물이 분포하였다. 귀화율은 3.72%, 도시화지수는 4.14%로 확인되어 비교적 낮은 비율로 나타났다.

• 한국환경복원기술학회지
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• 제23권6호
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• pp.87-107
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• 2020

The purpose of this study is to present the basic data for maintenance and management of river ecosystem by surveying and analysing the kinds and their characteristics of vascular plants in Bukcheon stream, Gyeongju-si, South Korea. The numbers of vascular plants were summarized as 428 taxa including 92 families, 265 genera, 3 subspecies, 24 varieties, 6 forms, 5 hybrids and 5 cultivars. Among the identified taxa, there were 90 planted species. The endangered wild species was Cicuta virosa, and the rare plants were 5 taxa including Prunus × yedoensis, Juniperus chinensis L. var. sargentii and so on. The Korean endemic plants were 5 taxa Populus × tomentiglandulosa, Salix koriyanagi, Lespedeza maritima, Forsythia koreana and Aster pseudoglehni. The specific plants by floristic region were 26 taxa including 2 taxa of grade V, 3 taxa of grade IV, 2 taxa of grade III, 8 taxa of grade II and 11 taxa of grade I. The naturalized plants were 81 taxa including Euphorbia maculata, Erigeron strigosus, Vulpia myuros and so on. The invasive alien plants were 7 taxa including Humulus scandens, Rumex acetosella, Ambrosia artemisiifolia, Ambrosia trifida, Lactuca seriola, Symphyotrichum pilosum and Paspalum distichum.

• Applied Biological Chemistry
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• 제22권2호
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• pp.97-100
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• 1979

다류제품(茶類製品)의 품질(品質)을 좌우(左右)하는 다엽(茶葉)의 tannin, caffeine을 지역별(地域別) 및 야생다엽(野生茶葉)과 재배다엽별(栽培茶葉別)로 5월(月), 7월(月), 9월(月)에 적채(摘采)하여 분석(分析) 비교(比較)하였고 2종(種)의 3번재배다엽(番栽培茶葉)의 향기성분(香氣成分)을 분석(分析)하여 다음과 같은 결과(結果)를 얻었다. 1. Tannin의 함량(含量)은 $10{\sim}14%$ 범위(範圍)로 타(他) 중국종(中國種)과 같은 양(量)이며 정채시기(摘采時期)가 1,2,3기(期)에 따라 점차 증가(增加)하였으며 지역간(地域間) 및 야생다엽(野生茶葉)과 재배다엽간(栽培茶葉間)의 차이(差異)는 없었다. 2. Caffeine의 함량(含量)은 $1.5{\sim}3%$의 범위(範圍)로 타(他) 중국종(中國種)과 같은 양(量)이며 지역간(地域間) 및 야생다엽(野生茶葉)과 재배다엽간(栽培茶葉間)의 차이(差異)는 없었다. 3. 향기성분(香氣成分)은 두 재배다엽간(栽培茶葉間)에 비슷한 pattern이며 32개(個)의 peak 중(中) phenol, iso-butyl aldehyde, n-butyl aldehyde, iso-valeraldehyde, n-butyl alcohol, iso-amyl alcohol, iso-valeric acid, benzaldehyde, n-valeric acid 및 linalool 의 10종(種)을 동정(同定)하였다.

• 한국자원식물학회지
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• 제22권6호
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• pp.558-570
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• 2009

The vascular plants in Jeju composed of 21 families 62 genera, 190 species, 7 varieties with 197 taxa in Pteridophyta, 3 families 5 genera, 7 species, 3 forma with 10 taxa in gymnosperm (Coniferophyta) and 143 families 703 genera, 1,622 species, 114 varieties and 47 forma with 1,783 taxa in Endospermae. The total number of taxa was 1,990 consisting 167 families, 770 genera, 1,818 species, 121 varieties and 50 forma. Three families, 4 genera 4 species and 1 variety in Pteridophyta and 1 family, 1 genus I species, 1 forma of Coniferophyta were endemic to Jeju. Five families, 8 genera and 8 species in the Monocotyledonae of Endospermae and 23 families, 32 genera, 21 species, 16 varieties and 7 forma and 44 taxa in Cholipetalae, and 9 families, 24 genera, 12 species, 13 varieties and 7 forma, total 32 taxa in Sympetalae were endemic to Jeju. Total 90 taxa with 41 families, 69 genera, 46 species, 29 varieties and 15 forma were drawn up as endemic plants in Jeju. As the numbers show on, Jeju has more biodiversity especially plant diversity than any other places in Korea. It was an important region in regard to geographical position. The rarity on plants from Jeju has been assessed based on the IUCN red list categories and criteria at both regional and global levels. There was one species in each extinct (EX) and extinct in the Wild (EW). The EX and EW species were Rhododendron saisiuense Nakai (Ericaceae) and Asplenium antiquum Makino (Aspleniaceae), respectively. Three taxa, Rhododendron dauricum L. (Ericaceae), Lycopodium sieboldii Miq., and Lycopodiella cernua (L.) Serm (Lycopodiaceae) were species that is extinct in the region (RE). Sixty-one taxa were critically endangered (CR), 13 were endangered (EN), and 83 were vulnerable (VU) at regional level. The taxa listed on a Red List corresponds 26.9% of total taxa in Jeju. At global level, there were 19 taxa in CR, 4 in EN, and 1 in VU (Vulnerable) as the category of threat. The rest taxa (133 taxa) were classified as Least Concern (LC). According to the results of the assessment, conservation measures must be taken for total of 157 species that were categorized in threaten including one of EX, one of EW and three extinct in the region immediately. Of 157 species, 61 were CR, 13 are EN and 83 were VU.

• Journal of Plant Biotechnology
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• 제34권1호
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• pp.47-53
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• 2007

To assess the risk of genetically modified (GM) rice on the agricultural ecosystem, agronomic characteristics, pollen longevity and outcrossing rate between GM (Iksan 483 and Milyang 204) and non-GM (their wild types and female parents) varieties were investigated using the bar gene as a tracer marker in paddy field. The agronomic characteristics of two GM rice were similar to their female-parents (non-GM rice) except heading date and 1,000 grain weight of Iksan 483, and they did not show a difference by the introgression of the bar gene as the genetic traits of rice varieties. Pollen viability was more than 90% just after shedding, and it was rapidly decreased below 50% at 5 minutes after shedding both GM and non-GM varieties. The Pollen longevity was lost after 30 minutes of anthesis. When the distance of gene flow from GM to non-GM rice detected to 6 m from the edge of GM rice plant, the maximum distance of pollen dispersal was 4.5m and 3.9m in Iksan 483 and Milyang 204, respectively, and that was increased in order of west, south, east, and north to the dominant wind direction, west-south. Mean outcrossing rate was very low as 0.003 and 0.001% within 1.5 m from the edge of Iksan 483 and Milyang 204, and the GM hybrids by the pollen dispersal did not detected over 4.5 m from the edge of GM rice plant. The results may help to establish the strategy which reduce the risk of pollen-mediated gene flow between GM and non-GM rice.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2021년도 춘계학술대회
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• pp.38-38
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• 2021

The seeds of rice with variable status were examined the germination rate after 10 years of long-term storage (-18℃) conservation. For seeds of wild relatives, 2 accessions were examined and germination rate of all accessions showed no changed after freezing conservation. For seeds of native germplasm, 1,259 accessions were examined and germination rate of 696 accessions was increased or showed no change after 10 years of long-term storage. Germination rate of 432 accessions was decreased with below 15% of initial germination rate. For 79 accessions of native germplasm, germination rate of seeds was decreased with above 15% of initial germination rate after 10 years of long-term storage, which is needed to be rejuvenated. For seeds of developed varieties, 873 accessions were examined and germination rate of 486 accessions of developed varieties was increased or showed no change after 10 years of long-term storage. Germination rate of 251 accessions was decreased with below 15% of initial germination rate. For 25 accessions of developed varieties, germination rate of seeds was decreased with above 15% of initial germination rate after 10 years of long-term storage, which is needed to be rejuvenated. For seeds of developed line, 2,131 accessions were examined and germination rate of 1,245 accessions of developed line was increased or showed no change after 10 years of long-term storage. Germination rate of 588 accessions was decreased with below 15% of initial germination rate. For 96 accessions, germination rate of seeds was decreased with above 15% of initial germination rate, which is needed to be rejuvenated.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권1호
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• pp.23-33
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• 2007

A simple and reliable cryo technique using desiccation and slow freezing of winter dormant buds was employed for 238 core collection of mulberry germplasm collected from diverse geographical regions and maintained under tropical conditions in the ex situ field gene bank to develop long-term biodiversity conservation for ensuring sustainable utilization of these valuable resources. Desiccation and freezing tolerance of bud grafts and excised shoot apices in the axillary buds of different Morus species under in vivo and in vitro condition indicated species-specific variation and most of the wild Morus species were found sensitive. In vitro regeneration and cryopreservation($-196^{\circ}C$) protocols using differentiated bud meristem like axillary winter dormant buds were worked out for a wide range of Morus species, land races, wild and cultivated varieties. Successful cryopreservation of mulberry winter dormant buds of different accessions belonging to M. indica, M. alba, M. latifolia, M. cathayana, M. laevigata, M. nigra, M. australis, M. bombycis, M. sinensis, M multicaulis and M. rotundiloba was achieved. Among wild species Morus tiliaefolia, and M. serrata showed moderate recovery after cryopreservation. Survival rates did not alter after three years of cryopreservation of different Morus species. ISSR markers were used to ascertain the genetic stability of cryopreserved mulberry, which showed no difference detected among the plantlets regenerated from frozen apices in comparison to the non-frozen material.