• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.442-448
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• 1993

The aims of the work were to examme the variability induced by EMS (ethyl methanesulfonate) mutagenesis of soybean plants, and to isolate mutants altered in nodulation and other growth characters. Seeds of two soybean cultivars, ‘Hwanggeumkong’ and ‘Baegunkong’ were treated with 30 and 50mM EMS(pH 7.0) for 6 hours and were planted directly in the field. Field emergency of$M_1 seed was averaged to be 61.0%, and frequency of plants with chlorophyll-deficient sectors of the first trifoliolate is about 0.7%. Regardless of varieties and does of EMS, $M_1 plant injury at harvest was present in plant height, pod and seed number per plant when compared to those of original-type soybean plants. The $M_2 variability of nodulation process induced by EMS treatment was found to be narrower than that of shoot dry weight. On the basis of the occurrence of chlorophyll-deficient plants, mutated cell frequency within $M_1 seed ranged from 5.3% to 84.2%, suggesting that mutation frequency on the $M_1 seed induced by EMS occurred partly and randomly regardless of varieties and doses of EMS. The putative mutant, which had more nodulation than original-type plant, was short in plant height. Sparse-nodulating soybean mutant was lower in leaf chlorophyll content and showed reduced growth.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.89-94
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• 2000

In order to induce the mutants of Gentiana axillariflora Leveille, nodes were cultured on Schenk and Hilderbrandt (SH) medium containing TDZ 2 mg/L, BAP 2mg/L, GA3 0.5 mg/L and 0.1 mg/L NAA and each mutagen of ethylmethanesulfate (EMS), colchicine, N-methyl-N-nitrosourea (MNU), and sodium azide (NaN$_3$) through filtration. Comparision of morphological characteristics and survival rate in each mutant plants differed depending on mutagen sources and their concentrations. When EMS were treated on nodes, the regenerated plants was thin and albino, regenerated shoots appeared 'erectoides type' and get twisted. The case of colchicine were treated on nodes, the survival rate was from 84% to 97% at ail concentration after 30days but the rate of survival was decreased about 50% at 200 $\mu$M after 60days. The treatment of NaN$_3$200 $\mu$M was not survived. The survival rate was extremely decreased in MNU treatment at 500$\mu$M, according to concentrations two types of leaf characteristic were obtained. Type I of leaf characteristic was modified from oblanceolate to oboid at leaf shape and type II of leaf characteristic was modified from light green to dark violet at leaf color. RAPD analysis was carried out to check the genetic modification of regenerated plants by mutagen treatments. Three polymorphic DNA fragments out of thirty-seven obtained by RAPDs were observed in regenerated plants using 5 decamer primers.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.5
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• pp.50-59
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• 2006

This study was initiated to investigate soil chemical properties under different soil systems. Data such as soil acidity(pH), electrical conductivity(EC), organic matter content(OMC), and cation exchange capacity(CEC) were analyzed with samples from multi-layer, USGA, and mono-layer systems. N, P, K and micronutrients were also measured. Multi-layer system was built up to 60-cm depth with rootzone layer, intermediate layer and two drainage layers. USGA system 45 centimeters deep was constructed with rootzone layer, intermediate layer and drainage layer. Mono-layer system, however, was made only with a 30-cm rootzone layer. Differences were observed in soil pH, EC, OMC, CEC and micronutrients. Soil pH was acceptable for turfgrass growth a year after establishment, being 5.5 to 6.5 in the study. Differences were greatly observed for EC among soil systems. Values of EC for multi-layer, USGA, and mono-layer systems were 39.79, 31.26 and 103.54 uS/em, respectively. The increase rate was approximately 4 to 8 times greater with mono-layer system than those with other two systems. Therefore, it was necessary to avoid micronutrient deficiency such as Fe, Mn etc. through an effective management program in mono-layer system because of its faster potential feasibility of salt accumulation. The greatest OMC was associated with USGA system, being 0.97% which was 11% over that of the other systems. Slight differences were observed for CEC among them. Mono-layer system produced 1.45 me/100g, 10.3% and 8.9% lower in CEC than those of multi-layer and USGA system, respectively. Micronutrients such as Fe, Zn, and Mn etc. were below the level required for turf growth, regardless of soil systems. It was considered that one year after turf establishment was not enough to build up micronutrients in sand-based soil systems to the normal level for a turf growth. These results demonstrate that intensive management program including grow-in concept fertilization should be integrated into sand-based soil systems, even after a year in establishment. Regular nutrient monitoring by soil analyses is a strong necessity to decide the kinds and amount of fertilizer. Also, strategic management program must be selectively employed according to sports turf soil systems.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.310-311
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• 2009

농업현장에서 활용되는 농업용미생물의 효능을 평가하고 현장실용화를 제고할 목적으로 본 시험을 수행하였다. 8개 지자체를 대상으로 친환경농업 특성화 지원사업 현황을 조사하고, 지자체별 미생물 활용수준을 평가하였으며, 각 지자체별로 활용되는 미생물을 수집하여 항균활성, siderophore 생성, IAA 생성, 질소고정, 인산가용화 능력 및 작물생육에 미치는 영향을 분석하였다. 지자체에서 활용하는 미생물은 주로 유산균, 고초균, Bacillus속 세균, 광합성균, 효모 및 EM 등으로 몇가지 종류의 미생물을 활요하는 것으로 조사되었고, 배양을 위한 배지는 대부분 균주를 개발한 대학 또는 산업체에서 공급받는 것으로 나타났으며, 배양기술 측면에서 볼 때 단순 배양 보급하는 지자체가 2개소, 산-학-연간 공급네트워크 및 대량배양체계를 구축하여 미생물을 활용하는 지자체가 7개소, 미생물 대량배양체계를 구축하고 병해충 관리연구를 수행하는 지자체가 1개소 그리고 미생물 선발, 특성검정 및 효과 평가 등 개발 및 응용을 추진하는 지자체가 1개소인 것으로 나타나 지자체에 따라 활용기술 수준은 큰 차이를 보였다. 지자체 공급 농업미생물의 항균활성을 조사한 결과, 고초균, 효모, 유산균, 광합성균, Bacillus속 세균 모두에서 균주에 따라 항균활성을 보였는데, 특히 Bacillus 속 세균이 높은 빈도로 황균활성을 보이는 것으로 나타났다. 철 킬레이트 능력 (Siderophore 형성능)에 있어서는 5개 광합성 균주 중 1균주가, 5종의 효모 중 1균주만이 활성을 보인 반면, Bacillus속 세균(고초균 포함)의 경우에는 11개 균주 모두 활성을 보였다. 작물 생육과 밀접한 관계가 있는 IAA(Indole acetic acid)의 생성능에 있어서는 광합성균이 5균주 중 4균주가 활성을 보여 비교적 생성능이 높은 것으로 나타났으며, Bacillus 속 세균의 경우에는 11균주 중 8개 균주가 활성을 보여 광합성균 다음으로 높은 반도를 나타냈다. 효모의 경우에는 5균주 중 1개 균주가 IAA를 생성하는 것으로 나타났다. 질소고정능에 있어서는 광합성균은 5균주 중 3균주, Bacillus 속세균 11균주 중 6균주가, 효모는 5균중 1균주가 활성을 보인 반면, 유산균 중에는 단 한 균주도 질소 고정능을 보이지 않았다. 연작재배에 따라 토양 내에 축적되는 인산의 가용화능을 분석한 결과, 수집한 대부분의 유산균은 높은 활성을 보인 반면 기타 미생물은 인산가용화능이 거의 없는 것으로 나타났다. 결론적으로 Bacillus 속 세균은 항균활성이 높고, 작물생육과 밀접한 IAA 생성 및 질소고정능력을 보유 하고 있는 것으로 나타나 친환경 작물재배시 병 발생을 줄이고 작물생장을 촉진할 수 있는 미생물로 평가되었다. 농업현장에서 기능성 및 효능을 고려하여 미생물을 잘 활용하면 병 발생 관리 및 생산성 향상에 도움이 되리라 판단된다.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.134-138
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• 1997

The objective of this study was to examine the effect of phosphorus deficiency on nitrogen fixation and photosynthesis of nitrogen fixing soybean plant under $CO_2$ enrichment condition. The soybean plants(Glycine max [L.] Merr.) inoculated with Bradyrhizobium japonicum MN 110 were grown with P-stressed(0.05 mM-P) and control(1 mM-P) treatment under control$(400\;{\mu}l/L\;CO_2)$ and enrichment$(800\;{\mu}l/L\;CO_2)$ enviromental condition in the phytotron equipped with high density lamp$(1000\;{\mu}Em^{-2}S^{-1})$ and $28/22^{\circ}C$ temperature cycle for 35 days after transplanting(DAT). At 35 DAT, phosphorus deficiency decreased total dry mass by 64% in $CO_2$ enrichment condition, and 51% in control $CO_2$ condition. Total leaf area was reduced significantly by phosphorus deficiency in control and enriched $CO_2$ condition but specific leaf weight was increased by P deficiency. Phosphorus deficiency significantly reduced photosynthetic rate(carbon exchange rate) and internal $CO_2$ concentration in leaf in both $CO_2$ treatments, but the degree of stress was more severe under $CO_2$ enrichment condition than under control $CO_2$ environmental condition. In phosphorus sufficient plants, $CO_2$ enrichment increased nodule fresh weight and total nitrogenase activity(acetylene reduction) of nodule by 30% and 41% respectively, but specific nitrogenase activity of nodule and nodule fresh weight was not affected by $CO_2$ enrichment in phosphorus deficient plant at 35 DAT. Total nitrogen concentrations in stem, root and nodule tissue were significantly higher in phosphorus sufficient plant grown under $CO_2$ enrichment, but nitrogen concentration in leaf was reduced by 30% under $CO_2$ enrichment. These results indicate that increasing $CO_2$ concentration does not affect plant growth under phosphorus deficient condition and phosphorus stress might inhibit carbohydrate utilization in whole plant and that $CO_2$ enrichment could not increase nodule formation and functioning under phosphorus deficient conditions and phosphorus has more important roles in nodule growth and functioning under $CO_2$ enrichment environments than under ambient condition.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.17-22
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• 2011

This study was for developing leaf chlorophyll mutant cultivars of Cymbidium goeringii by ethyl-methanesulfonate(EMS) treatment. Chlorophyll mutant rhizomes were easily produced by 0.2% EMS treatment in this genus. Among the mutants, they became dark brown about 50% of the rhizomes. When the dark-brown rhizomes were cultured in a solidified MS medium, new rhizomes were formed from part of the old ones. Chlorophyll mutant rhizomes were obtained from subcultured meristem tissues of newly-formed rhizomes. The rhizomes were cut and subcultured for a year and then became mutant plants. As the results, they produced 4 kinds of leaf mutant cultivars; zigzag-striped, comb-striped, net-striped, and dwarf types, indicating that the EMS treatment in the rhizome could produce versatile leaf chlorophyll regulating mutants. These results suggest that our method is useful for developing leaf mutant cultivars of this planta which they are estimated as higher commercial values.

• KSBB Journal
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• v.15 no.6
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• pp.566-572
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• 2000

Experimental studies were carried out to develop an osmotolerant mutant of Candida magnoliae JH and to determine the optimum concentrations of carbon and nitrogen sources to improve erythritol yield and productivity. Mutants of C. magnoliae JH were prepared by treatment with ethylmethane sulfonate, and osmotolerant mutants were isolated from the agar plate colonies containing 2.5 M KCI. Among the mutants isolated, one mutant M26 was finally selected based on erythritol yield and productivity. In shake flask culture, glucose proved to be the best carbon source and the optimum yeast extract concentration was 5 g/L based on 100 g/L glucose. The erythritol yield and productivity of mutant M26 were greater than wild type in 100 g/L glucose medium. in the fermentation experiments, erythritol production increased with increased glucose concentration, up to a limit of 250 g/L. The maximum concentration of erythritol achieved 127.5 g/L, and the yield and productivity of erythritol production were 51.0% and 0.63 g/L-h, respectively.

• ALGAE
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• v.29 no.2
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• pp.137-152
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• 2014

Mixotrophic protists play diverse roles in marine food webs as predators and prey. Thus, exploring mixotrophy in phototrophic protists has emerged as a critical step in understanding marine food webs and cycling of materials in marine ecosystem. To investigate the feeding of newly described mixotrophic dinoflagellate Ansanella granifera, we explored the feeding mechanism and the different types of species that A. granifera was able to feed on. In addition, we measured the growth and ingestion rates of A. granifera feeding on the prasinophyte Pyramimonas sp., the only algal prey, as a function of prey concentration. A. granifera was able to feed on heterotrophic bacteria and the cyanobacterium Synechococcus sp. However, among the 12 species of algal prey offered, A. granifera ingested only Pyramimonas sp. A. granifera ingested the algal prey cell by engulfment. With increasing mean prey concentration, the growth rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but became saturated at a concentration of $434ngCmL^{-1}$ (10,845 cells $mL^{-1}$). The maximum specific growth rate (i.e., mixotrophic growth) of A. granifera feeding on Pyramimonas sp. was $1.426d^{-1}$, at $20^{\circ}C$ under a 14 : 10 h light-dark cycle of $20{\mu}Em^{-2}s^{-1}$, while the growth rate (i.e., phototrophic growth) under similar light conditions without added prey was $0.391d^{-1}$. With increasing mean prey concentration, the ingestion rate of A. granifera feeding on Pyramimonas sp. increased rapidly, but slightly at the concentrations ${\geq}306ngCmL^{-1}$ (7,649 cells $mL^{-1}$). The maximum ingestion rate of A. granifera feeding on Pyramimonas sp. was 0.97 ng C $predator^{-1}d^{-1}$ (24.3 cells $grazer^{-1}d^{-1}$). The calculated grazing coefficients for A. granifera feeding on co-occurring Pyramimonas sp. were up to $2.78d^{-1}$. The results of the present study suggest that A. granifera can sometimes have a considerable grazing impact on the population of Pyramimonas spp.

• Journal of Life Science
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• v.28 no.12
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• pp.1424-1431
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• 2018

We prepared flocculated detritus-like organic marine snow originating from various organisms by fermentation using microorganisms; this fermented organic material was fed to the leptocephali of the eel (Anguilla japonica) to investigate whether or not such organic matter was an appropriate food source for the larvae. A strain was isolated from a biofloc technology system used to culture fish, and seven types of organic material from hen's egg, eel muscle, tuna muscle, lugworm, shrimp, manila clam, mussel, and sea squirt were fermented using isolated bacteria (Bacillus sp.). The fermented matter did not show any specific form and was larger than $10-20{\mu}m$ but no more than $100{\mu}m$ in size. Four diets (A-D) were prepared using the various fermented products, and the larvae were fed the prepared food from 20 days after hatching. The leptocephali fed the A, B, and C diets survived until 37, 39, and 37 days after hatching, respectively. However, the leptocephali fed the D diet survived for 60 days after hatching. The protein content of each diet was very similar, but the n-3 HUFA concentration in the D diet was approximately twice as high as that of the others.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.1
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• pp.25-32
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• 2019

K-BEMS System was introduced to reduce peak load and to save total energy of the 200 buildings that KEPCO headquarter and branch offices use. And K-BEMS system is composed of PV, battery, and hybrid PCS. KEPCO research institute has carried out this K-BEMS research project for 3 years since January 2016. In this paper, the results of the project are shown. 9 modes of test results of K-BEMS system and are operational problems were analyzed. And measures to cure the trouble are also suggested. Batteries are operated more than 20% of SOC, and less than 20% of SOC battery protection switches are automatically shutting down the system and the system no longer respond to EMS, ending the supply of PV, and so therefore to continue the PV power supply it was turn out to be necessary that the EMS should automatically change its policy to change PV only supply mode automatically when the Battery Switch automatically operated. To operate the system continuously and automatically, it is necessary to modify the minimum operational SOC value, and in addition to that the EMS computer must remember the last shut-down SOC and Voltage which interrupted the system and add some margin to reflect the measurement error in the system.