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Sorption Efficiency of the Bamboo Charcoal to Remove the Cesium in the Contaminated Water System (오염수계 내 세슘 제거를 위한 대나무 활성탄의 흡착효율 규명)

  • Ahn, Joungpil;Lee, Minhee
    • Economic and Environmental Geology
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    • v.51 no.2
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    • pp.87-97
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    • 2018
  • The cesium (Cs) removal from the contaminated water system has been considered to be difficult because the cesium likes to exist as soluble phases such as ion and complexes than the solid in water system. Many researches have focused on developing the breakthrough adsorbent to increase the cesium removal efficiency in water. In this study, the laboratory scale experiments were performed to investigate the feasibility of the adsorption process using the bamboo charcoal for the Cs contaminated water system. The Cs removal efficiency of the bamboo charcoal were measured and the optimal adsorption conditions were determined by the adsorption batch experiments. Total 5 types of commercialized bamboo charcoals in Korea were used to identify their surface properties from SEM-EDS and XRD analyses and 3 types of bamboo charcoals having large specific surface areas were used for the adsorption batch experiment. The batch experiments to calculate the Cs removal efficiency were performed at conditions of various Cs concentration (0.01 - 10 mg/L), pH (3 - 11), temperature ($5-30^{\circ}C$), and adsorption time (10 - 120 min.). Experimental results were fitted to the Langmuir adsorption isotherm curve and their adsorption constants were determined to understand the adsorption properties of bamboo charcoal for Cs contaminated water system. From results of SEM-EDS analyses, the surfaces of bamboo charcoal particles were composed of typical fiber structures having various pores and dense lamella structures in supporting major adsorption spaces for Cs. From results of adsorption batch experiments, the Cs-133 removal efficiency of C type bamboo charcoal was the highest among those of 3 bamboo charcoal types and it was higher than 75 % (maximum of 82 %) even when the initial Cs concentration in water was lower than 1.0 mg/L, suggesting that the adsorption process using the bamboo charcoal has a great potential to remove Cs from the genuine Cs contaminated water, of which Cs concentration is low (< 1.0 mg/L) in general. The high Cs removal efficiency of bamboo charcoal was maintained in a relatively wide range of temperatures and pHs, supporting that the usage of the bamboo charcoal is feasible for various types of water. Experimental results were similar to the Langmuir adsorption model and the maximum amount of Cs adsorption (qm:mg/g) was 63.4 mg/g, which was higher than those of commercialized adsorbents used in previous studies. The surface coverage (${\theta}$) of bamboo charcoal was also maintained in low when the Cs concentration in water was < 1.0 mg/L, investigating that the Cs contaminated water can be remediated up with a small amount of bamboo charcoal.

Forest Community Structure of Mt. Bukhan Area (북한산 지역의 삼림군집구조에 관한 연구)

  • 박인협;이경재;조재창
    • Korean Journal of Environment and Ecology
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    • v.1 no.1
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    • pp.1-23
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    • 1987
  • To investigate the forest structure of Mt. Bukhan. ranging from Seoul to Kyongkido, twenty plots were set up by the vegetation physiognomy and vegetation analysis was carried out. According to the leading dominant tree species in canopy stratum, forest communities were classified into three large groups of natural forest communities, semi-natural forest communities and artificial forest communities, and each of them covered 82.64, 7.03, and 5.71% of Mt. Bukhan area, respectively. Pure or mixed natural forest communities of Pinus densiflora and Quercus mongolica were major forest communities and covered 70.8% of Mt. Bukhan area. The important planted tree species were Robinia pseudoacacia, Pinus rigida, and Alnus birsuta and they were mainly planted at the southern slope and roadside. The degree of human disturbance of vegetation of 8, 7, and 6 area covered 82.64, 0, and 12.74%, respectively. According to forest dimensions, most of forest communities were young aged forests of which mean DBH was 20cm and canopy height below 10m. However, a few mature forest communities of Pinus densiflora or Quercus mongolica were found in the small area. The range of Shannon's species diversity of major natural forest communities, pure or mixed forest communities of Pinus densiflora and Quercus mongolica was 1.085~1.242. According to stand dynamic analysis by DBH class distribution, the present Quercus mongolica communities arid Robinia pseudoacacia communities may last long their present forest structure and most of other communities may be succeeded to Quercus mongolica communities, however, a few communities invaded by Robinia pseudoacacia and Quercus aliena-Quercus acutissima communities may be succeeded to Robinia pseudoacacia communities and Quercus aliena communities, respectively. DCA was the most effective method of this study. DCA ordination were showed that successional trends of tree species seem to be from Pinus densiflora through Quercus serrata. Prunus sargrntii. Sorbus alnifolia to Q. mongolica. Fraxinus mandsburica, F. rhynchophylla in the upper layer and from Zanthoxylum schinifolium, Lespedeza crytobotrya trough Rhus trichocarpa. Rh. verniciflua. Rhododendron mucronulatum. Rh. schlippenbachii to Acer pseudo-sieboldianus. Magnolia sieboldii, Euonymus sieboldianus.

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Removal of Cochlodinium polykrikoides using the Dredged Sediment from a Coastal Fishery (연안어장 준설퇴적물을 이용한 Cochlodinium polykrikoides 제거)

  • Sun, Young-Chul;Kim, Myoung-Jin;Song, Young-Chae;Ko, Seong-Jeong;Hwang, Eung-Ju;Jo, Q-Tae
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.1
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    • pp.53-60
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    • 2010
  • In the present study, experiments have been performed to investigate the possibility of removing Cochlodinium polykrikoides using the dredged sediment from a coastal fishery and then to derive the optimal conditions; the amount and particle size of dredged sediment besprinkled into water, the thermal treatment, the types and amounts of additives, and the depth profile of Cochlodinium polykrikoides. Results showed that the optimal amount of dredged sediment besprinkled into water was 6~10 g/L, and the removal efficiency of Cochlodinium polykrikoides after the reaction time for 60 min was 73~93%. Note that, in the real sea water, it is necessary to besprinkle 6~10 $kg/m^3$ of dry dredged sediment on a unit area (1 $m^2$). With decreasing particle size, Cochlodinium polykrikoides could be more efficiently removed. The removal efficiency was 93% with the dredged sediment smaller than 100 ${\mu}m$, whereas it was 51% with that of 100 ${\mu}m$ ${\mu}m$. Since most of dredged sediment (over 90%) was smaller than 100 ${\mu}m$, high efficiency could be obtained by besprinkling only the dredged sediment without pre-treatment. CaO was found to be an effective additive in promoting the removal efficiency (up to 99%). The optimal amount of additive was 5~10%, however, it was necessary to use as small amount of an additive as possible in order to avoid the sharp increase in pH. The removal efficiency increased with increasing depth profile of Cochlodinium polykrikoides. The removal efficiency was 83% at 5 cm depth, whereas it was 93% at 50 cm depth. In the sea water, red tide occurred within 3 m depth, and furthermore most Cochlodinium polykrikoides existed within 1 m depth. It was, therefore, expected that higher removal efficiency of Cochlodinium polykrikoides could be obtained when the dredged sediment was besprinkled into the sea water. The removal efficiency of Cochlodinium polykrikoides was up to 93% when the dredged sediment (<100 ${\mu}m$) was besprinkled into water at the ratio of 10 g/L. This result was comparable to that obtained with loess (90~97%). All the results in the present study indicated that the dredged sediment from a coastal fishery could be successfully used as a substitute of loess for removing the red tide alga.

A Study on the Screening of the Novel Genes Associated with Lysosomal Trafficking and Mutation Detection in Fibroblasts of the Patients with Mucolipidosis type II and III (리소좀 교통 이상을 초래하는 뮤코지방증 2형과 3형 환자의 섬유아세포를 이용한 신규 유전자 탐색 및 돌연변이에 대한 연구)

  • Song, Seng Mi;Chang, Soo Hee;Paik, Kyung Hoon;Jin, Dong-Kyu
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.5 no.1
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    • pp.65-75
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    • 2005
  • Purpose: To understand genetic differences and similarities between mucolipidosis and control. Methods: Using the fibroblast of the mucolipidosis II and control, forward and reverse subtracted libraries were constructed. Among these clones, we investigated mutations in the GNPTA (MGC4170) gene, which codes for the ${\alpha}/{\beta}$ subunits of phosphotransferase, and in the GNPTAG gene, which codes for the ${\gamma}$ subunits in 5 Korean patients with mucolipidosis type II or IIIA. Result: Several differentially expressed cDNAs were cloned and their sequences were determined. Mutation analysis of the interested gene, GNPTA was performed and we identified 7 mutations in the GNPTA gene, but none in the GNPTAG gene. The mutations in type II patients included p.Q104X(c.310C>T), p.R1189X(c.3565C>T), p.S1058X(c.3173C>G), p.W894X(c.2681G>A) and p.H1158fsX15(c.3474_3475delTA), all of which are non-sense or frame shift mutations. However, a splicing site mutation, IVS13+1G>A (c.2715+1G>A) was detected along with a non-sense or a frame shift mutation (p.R1189X or p.E858fsX3(c.2574_2575delGA)) in two mucolipidosis type IIIA patients. Conclusion: This report shows that mutations in the GNPTA gene coding for the ${\alpha}{\beta}$subunits of phosphotransferase, and not mutations in the GNPTAG gene, account for most of mutations found in Korean patients with mucolipidosis type II or IIIA.

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Characteristics of Vegetation Structure of Managed Area by Oak Wilt Disease in Bukhansan National Park (북한산국립공원 참나무시들음병 방제지역 식생구조 특성 연구)

  • Han, Bong-Ho;Choi, Jin-Woo;Yeum, Jung-Hun;Lee, Kyong-Jae
    • Korean Journal of Environment and Ecology
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    • v.28 no.3
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    • pp.342-356
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    • 2014
  • This study aims to provide the fundamental data for restoration through the analysis of vegetation structure characteristic for managed area with deforest and fumigation among the places damaged by oak wilt disease in Bukhansan National Park. Study areas were selected in six damaged areas with 18 plots ($20m{\times}20m$) including comparing plots between year 2006 and year 2011 after preliminary study finding the exact location with easy access. Analysis items are density and coverage of under story layer, Importance Percentage of under story layer and Importance Percentage of urban adapted species and alien species. As a result, density and coverage under the canopy layer's vegetation was higher than comparing plot in Musugol valley and Soquicheon valley which 4 years and more passed. And Wondobong, Darakwon, Doseonsa and Dobong valley which had not been passed 3 years after deforestation and fumigation decreased in those of vegetation. However, the plots in Wondobong and Doseonsa was analyzed to be higher in density of shrubs than comparing plot. In terms of distirbution of species in under canopy layer which is grown as a upper vegetation, Quercus serrata and Sorbus alnifolia dominated each other in under canopy layer except for Wondobong and Darakwon. Wondobong continuously maintained Quercus mongolica and Q. mongolica and Pinus densiflora dominated in under canopy layer of Darakwon. S. alnifolia which is Urban adapted species were distributed in most study areas. In terms of alien species, Magnolia obovata and Robinia pseudoacacia were newly intruded in the opened crown, and Pueraria thunbergiana was distributed in Soquicheon valley. As the result of soil analysis, acidification(pH 4.49) and low level of organic matter(3.23%), available phosphate(1.40mg/kg) and exchangeable cation were analyzed and it was considered that those environment poorly support the vegetation growth.

Applicability of plate tectonics to the post-late Cretaceous igneous activities and mineralization in the southern part of South Korea( I ) (한국남부(韓國南部)의 백악기말(白堊紀末) 이후(以後)의 화성활동(火成活動)과 광화작용(鑛化作用)에 대(對)한 판구조론(板構造論)의 적용성(適用性) 연구(硏究)( I ))

  • Min, Kyung Duck;Kim, Ok Joon;Yun, Suckew;Lee, Dai Sung;Joo, Sung Whan
    • Economic and Environmental Geology
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    • v.15 no.3
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    • pp.123-154
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    • 1982
  • Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.

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Floristic features of upland fields in South Korea (우리나라 밭 경작지에 출현하는 식물상 특성)

  • Kim, Myung-Hyun;Eo, Jinu;Kim, Min-Kyeong;Oh, Young-Ju
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.528-553
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    • 2020
  • Upland fields are characterized by dry environments, a high degree of disturbance by farming practices such as double-cropping, and a high diversity of crops compared to other field types. This study focused on the floristic composition and characteristics of upland fields in South Korea. Flora surveys were conducted in 36 areas in nine provinces at two times (June and August) in 2015. The results showed that the vascular plants in the upland fields in South Korea included 532 taxa, containing 100 families, 322 genera, 483 species, nine subspecies, 37 varieties, one form, and two hybrids. Among the 100 families, Asteraceae was the most diverse in species (75 taxa), followed by Poaceae (68 taxa), Fabaceae (34 taxa), Polygonaceae (21 taxa), Rosaceae (19 taxa), and Liliaceae (17 taxa). Based on the occurrence frequency of each species, Acalypha australis L. (100%), and Artemisia indica Willd. (100%) were the highest, followed by Humulus scandens (Lour.) Merr., Rorippa palustris (L.) Besser, Conyza canadensis (L.) Cronquist, Erigeron annuus (L.) Pers., Lactuca indica L., Commelina communis L., Digitaria ciliaris (Retz.) Koeler, Echinochloa crus-galli(L.) P.Beauv., Cyperus microiria Steud., and Oxalis corniculata L. The biological type of upland fields in South Korea was determined to be Th-R5-D4-e type. Rare plants were found in 11 taxa: Taxus cuspidata Siebold & Zucc, Magnolia kobus DC, Clematis trichotoma Nakai, Aristolochina contorta Bunge, Buxus sinica (Rehder & E.H.Wilson) M.Cheng var. koreana (Nakai ex Rehder) Q.L.Wang, Melothria japonica (Thunb.) Maxim, Mitrasacme indica Wight, Lithospermum arvense L., Carpesium rosulatum Miq., Allium senescens L., and Pseudoraphis sordida (Thwaites) S.M.Phillips & S.L.Chen. Ninety-seven taxa contained naturalized plants composed of 24 families, 68 genera, 97 species, one variety, and one form. The urbanization and naturalization indices were 30.5% and 18.4%, respectively.

A study of the plan dosimetic evaluation on the rectal cancer treatment (직장암 치료 시 치료계획에 따른 선량평가 연구)

  • Jeong, Hyun Hak;An, Beom Seok;Kim, Dae Il;Lee, Yang Hoon;Lee, Je hee
    • The Journal of Korean Society for Radiation Therapy
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    • v.28 no.2
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    • pp.171-178
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    • 2016
  • Purpose : In order to minimize the dose of femoral head as an appropriate treatment plan for rectal cancer radiation therapy, we compare and evaluate the usefulness of 3-field 3D conformal radiation therapy(below 3fCRT), which is a universal treatment method, and 5-field 3D conformal radiation therapy(below 5fCRT), and Volumetric Modulated Arc Therapy (VMAT). Materials and Methods : The 10 cases of rectal cancer that treated with 21EX were enrolled. Those cases were planned by Eclipse(Ver. 10.0.42, Varian, USA), PRO3(Progressive Resolution Optimizer 10.0.28) and AAA(Anisotropic Analytic Algorithm Ver. 10.0.28). 3fCRT and 5fCRT plan has $0^{\circ}$, $270^{\circ}$, $90^{\circ}$ and $0^{\circ}$, $95^{\circ}$, $45^{\circ}$, $315^{\circ}$, $265^{\circ}$ gantry angle, respectively. VMAT plan parameters consisted of 15MV coplanar $360^{\circ}$ 1 arac. Treatment prescription was employed delivering 54Gy to recum in 30 fractions. To minimize the dose difference that shows up randomly on optimizing, VMAT plans were optimized and calculated twice, and normalized to the target V100%=95%. The indexes of evaluation are D of Both femoral head and aceta fossa, total MU, H.I.(Homogeneity index) and C.I.(Conformity index) of the PTV. All VMAT plans were verified by gamma test with portal dosimetry using EPID. Results : D of Rt. femoral head was 53.08 Gy, 50.27 Gy, and 30.92 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. D of Rt. aceta fossa was 54.86 Gy, 52.40 Gy, 30.37 Gy, respectively, in the order of 3fCRT, 5fCRT, and VMAT treatment plan. Likewise, Lt. Femoral head showed average 53.68 Gy, 51.01 Gy and 29.23 Gy in the same order. The maximum dose of both femoral head and aceta fossa was higher in the order of 3fCRT, 5fCRT, and VMAT treatment plan. C.I. showed the lowest VMAT treatment plan with an average of 1.64, 1.48, and 0.99 in the order of 3fCRT, 5fCRT, and VMAT treatment plan. There was no significant difference on H.I. of the PTV among three plans. Total MU showed that the VMAT treatment plan used 124.4MU and 299MU more than the 3fCRT and 5fCRT treatment plan, respectively. IMRT verification gamma test results for the VMAT plan passed over 90.0% at 2mm/2%. Conclusion : In rectal cancer treatment, the VMAT plan was shown to be advantageous in most of the evaluation indexes compared to the 3D plan, and the dose of the femoral head was greatly reduced. However, because of practical limitations there may be a case where it is difficult to select a VMAT treatment plan. 5fCRT has the advantage of reducing the dose of the femoral head as compared to the existing 3fCRT, without regard to additional problems. Therefore, not only would it extend survival time but the quality of life in general, if hospitals improved radiation therapy efficiency by selecting the treatment plan in accordance with the hospital's situation.

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Brief Introduction of Research Progresses in Control and Biocontrol of Clubroot Disease in China

  • He, Yueqiu;Wu, Yixin;He, Pengfei;Li, Xinyu
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.45-46
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    • 2015
  • Clubroot disease of crucifers has occurred since 1957. It has spread to the whole China, especially in the southwest and nourtheast where it causes 30-80% loss in some fields. The disease has being expanded in the recent years as seeds are imported and the floating seedling system practices. For its effective control, the Ministry of Agriculture of China set up a program in 2010 and a research team led by Dr. Yueqiu HE, Yunnan Agricultural University. The team includes 20 main reseachers of 11 universities and 5 institutions. After 5 years, the team has made a lot of progresses in disease occurrence regulation, resources collection, resistance identification and breeding, biological agent exploration, formulation, chemicals evaluation, and control strategy. About 1200 collections of local and commercial crucifers were identified in the field and by artificiall inoculation in the laboratories, 10 resistant cultivars were breeded including 7 Chinese cabbages and 3 cabbages. More than 800 antagostic strains were isolated including bacteria, stretomyces and fungi. Around 100 chemicals were evaluated in the field and greenhouse based on its control effect, among them, 6 showed high control effect, especially fluazinam and cyazofamid could control about 80% the disease. However, fluzinam has negative effect on soil microbes. Clubroot disease could not be controlled by bioagents and chemicals once when the pathogen Plasmodiophora brassicae infected its hosts and set up the parasitic relationship. We found the earlier the pathogent infected its host, the severer the disease was. Therefore, early control was the most effective. For Chinese cabbage, all controlling measures should be taken in the early 30 days because the new infection could not cause severe symptom after 30 days of seeding. For example, a biocontrol agent, Bacillus subtilis Strain XF-1 could control the disease 70%-85% averagely when it mixed with seedling substrate and was drenching 3 times after transplanting, i.e. immediately, 7 days, 14 days. XF-1 has been deeply researched in control mechanisms, its genome, and development and application of biocontrol formulate. It could produce antagonistic protein, enzyme, antibiotics and IAA, which promoted rhizogenesis and growth. Its The genome was sequenced by Illumina/Solexa Genome Analyzer to assembled into 20 scaffolds then the gaps between scaffolds were filled by long fragment PCR amplification to obtain complet genmone with 4,061,186 bp in size. The whole genome was found to have 43.8% GC, 108 tandem repeats with an average of 2.65 copies and 84 transposons. The CDSs were predicted as 3,853 in which 112 CDSs were predicted to secondary metabolite biosynthesis, transport and catabolism. Among those, five NRPS/PKS giant gene clusters being responsible for the biosynthesis of polyketide (pksABCDEFHJLMNRS in size 72.9 kb), surfactin(srfABCD, 26.148 kb, bacilysin(bacABCDE 5.903 kb), bacillibactin(dhbABCEF, 11.774 kb) and fengycin(ppsABCDE, 37.799 kb) have high homolgous to fuction confirmed biosynthesis gene in other strain. Moreover, there are many of key regulatory genes for secondary metabolites from XF-1, such as comABPQKX Z, degQ, sfp, yczE, degU, ycxABCD and ywfG. were also predicted. Therefore, XF-1 has potential of biosynthesis for secondary metabolites surfactin, fengycin, bacillibactin, bacilysin and Bacillaene. Thirty two compounds were detected from cell extracts of XF-1 by MALDI-TOF-MS, including one Macrolactin (m/z 441.06), two fusaricidin (m/z 850.493 and 968.515), one circulocin (m/z 852.509), nine surfactin (m/z 1044.656~1102.652), five iturin (m/z 1096.631~1150.57) and forty fengycin (m/z 1449.79~1543.805). The top three compositions types (contening 56.67% of total extract) are surfactin, iturin and fengycin, in which the most abundant is the surfactin type composition 30.37% of total extract and in second place is the fengycin with 23.28% content with rich diversity of chemical structure, and the smallest one is the iturin with 3.02% content. Moreover, the same main compositions were detected in Bacillus sp.355 which is also a good effects biocontol bacterial for controlling the clubroot of crucifer. Wherefore those compounds surfactin, iturin and fengycin maybe the main active compositions of XF-1 against P. brassicae. Twenty one fengycin type compounds were evaluate by LC-ESI-MS/MS with antifungal activities, including fengycin A $C_{16{\sim}C19}$, fengycin B $C_{14{\sim}C17}$, fengycin C $C_{15{\sim}C18}$, fengycin D $C_{15{\sim}C18}$ and fengycin S $C_{15{\sim}C18}$. Furthermore, one novel compound was identified as Dehydroxyfengycin $C_{17}$ according its MS, 1D and 2D NMR spectral data, which molecular weight is 1488.8480 Da and formula $C_{75}H_{116}N_{12}O_{19}$. The fengycin type compounds (FTCPs $250{\mu}g/mL$) were used to treat the resting spores of P. brassicae ($10^7/mL$) by detecting leakage of the cytoplasm components and cell destruction. After 12 h treatment, the absorbencies at 260 nm (A260) and at 280 nm (A280) increased gradually to approaching the maximum of absorbance, accompanying the collapse of P. brassicae resting spores, and nearly no complete cells were observed at 24 h treatment. The results suggested that the cells could be lyzed by the FTCPs of XF-1, and the diversity of FTCPs was mainly attributed to a mechanism of clubroot disease biocontrol. In the five selected medium MOLP, PSA, LB, Landy and LD, the most suitable for growth of strain medium is MOLP, and the least for strains longevity is the Landy sucrose medium. However, the lipopeptide highest yield is in Landy sucrose medium. The lipopeptides in five medium were analyzed with HPLC, and the results showed that lipopeptides component were same, while their contents from B. subtilis XF-1 fermented in five medium were different. We found that it is the lipopeptides content but ingredients of XF-1 could be impacted by medium and lacking of nutrition seems promoting lipopeptides secretion from XF-1. The volatile components with inhibition fungal Cylindrocarpon spp. activity which were collect in sealed vesel were detected with metheds of HS-SPME-GC-MS in eight biocontrol Bacillus species and four positive mutant strains of XF-1 mutagenized with chemical mutagens, respectively. They have same main volatile components including pyrazine, aldehydes, oxazolidinone and sulfide which are composed of 91.62% in XF-1, in which, the most abundant is the pyrazine type composition with 47.03%, and in second place is the aldehydes with 23.84%, and the third place is oxazolidinone with 15.68%, and the smallest ones is the sulfide with 5.07%.

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Interspecific Competition of Paddy Rice Isogenic Lines in Plant Type with Some Perennial Weeds (수도초형(水稻草型)의 Isogenic Line과 다년생(多年生) 잡초(雜草)의 경합특성(競合特性) 연구(硏究))

  • Kim, I.K.;Guh, J.O.;Kwon, S.L.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.39-49
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    • 1983
  • By use of three paddy rice lines as the near-isogenic in plant type (Broom, Open, and Spread type in tillering angle), the interspecific competition patterns of rice plants with three important weed species (Cyperus serotinus, Eleocharis kuroguwai, and Potamogeton distinctus) under the three densities of weed standing (0.25 and 50 percent of the rice plants), were observed. Under the experimented conditions, paddy yields were varied more significantly with weed competition descriptions than with plant types of paddy rice. And spread typed rice was more competitive to the detected weed species, however, the broom and spread typed rice were to Potamogeton SP, among others. The result of the clustering analysis of crop-weed competition patterns, estimated by 1-Q mode correlation coefficients, indicated that the first-order component affecting the competition patterns of crop-weed was rather the plant types of rice than either weed species or weed standing densities.

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