• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.137-142
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• 2008

This study was conducted to evaluate the humification grade of compost, based on physico-chemical property and phyto-toxicity during the composting with three kinds of livestock manures and saw dust. The ratios of the compost, which was mixed with pig manure(P) and sawdust(S) were 4 : 6(PS-1), 5 : 5(PS-2) and 6 : 4(PS-3); poultry manure(PO) and sawdust(S) were 4 : 6(POS-1), 5 : 5(POS-2) and 6 : 4(POS-3); cow manure(C) and sawdust(S) were 4 : 6(CS-1), 5 : 5(CS-2) and 6 : 4(CS-3) by volume to volume, and they were decomposed for 60 days. In the result, the temperature in all treatments during composting rapidly increased above $65.4^{\circ}C$, and then gradually decreased to around $40^{\circ}C$. At 60 day, after the treatment, pH 5.9 ~ 8.0 at the incipient stage increased to 7.6 ~ 8.5, and the C/N ratio was 13.8 ~ 21.1 at the final composting stage. Germination Index(G.I.) showed in the range of 75.1 ~ 94.6 in all treatments at day 60. Therefore, it is likely recommended to take the best humification grade when the temperature maintains above $65^{\circ}C$ longer than a day at minimum, in the range of pH 6.5 ~ 8.5 for the final compost, under 20 of C/N ratio, and G.I. above 80. The level of G.I. above 80 should be the mature compost which could be used in the field without gas demage to crops.

• Korean Journal of Microbiology
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• v.50 no.3
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• pp.201-209
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• 2014

This study was carried out in order to develop a biological control of anthracnose of red pepper caused by fungal pathogens. In particular, this study focuses on the Colletotrichum species, which includes important fungal pathogens causing a great deal of damage to red pepper. Antagonistic bacteria were isolated from the soil of pepper fields, which were then tested for biocontrol activity against the Colletotrichum gloeosporioides anthracnose pathogen of pepper. Based on the 16S rRNA sequence analysis, the isolated bacterial strain CS-52 was identical to Bacillus sp. The culture broth of Bacillus sp. CS-52 had antifungal activity toward the hyphae and spores of C. gloeosporioides. Moreover, the substances with antifungal activity were optimized when Bacillus sp. CS-52 was grown aerobically in a medium composed of 0.5% glucose, 0.7% $K_2HPO_4$, 0.2% $KH_2PO_4$, 0.3% $NH_4NO_3$, 0.01% $MnSO_4{\cdot}7H_2O$, and 0.15% yeast extract at $30^{\circ}C$. The inhibition of spore formation resulting from cellulase, siderophores, and indole-3-acetic acid (IAA), were produced at 24 h, 48 h, and 72 h, respectively. Bacillus sp. CS-52 also exhibited its potent fungicidal activity against anthracnose in an in vivo test, at a level of 70% when compared to chemical fungicides. These results identified substances with antifungal activity produced by Bacillus sp. CS-52 for the biological control of major plant pathogens in red pepper. Further studies will investigate the synergistic effect promoting better growth and antifungal activity by the formulation of substances with antifungal activity.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.181-193
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• 2017

Mn-Fe phosphate mineral complexes included within the pegmatite are observed at Jurassic Cheolwon two-mica granite in Gyeonggi Massif, South Korea. The genetic evolution between the Cheolwon two-mica granite and pegmatite, and various trend of Mn-Fe phosphate minerals is made by later magmatic, hydrothermal, and weathering process based on mineralogical, geochemical analysis. The Cheolwon two-mica granite is identified as S-type granite, considering its chemical composition (metaluminous ~ peraluminous), post-collisional environment, low magnetic susceptibility, and existence of biotite and muscovite. The K-Ar age (ca. 153 Ma) of pegmatite is well coincident with age of the Cheolwon two-mica granite ($151{\pm}4Ma$). It indicates that these two rocks are originated from the same magma. Pegmatite indicates the LCT geochemical signature, and was classified as muscovite-rare element class / Li subclass / beryl type / beryl-columbite-phosphate subtype pegmatite. The triplite $\{(Fe^{2+}{_{0.4}},Mn_{1.6})(PO_4)(F_{0.9})\}$ is dominant phosphates in later magmatic stage which partly altered to leucophosphite $\{KFe^{3+}{_2}(PO_4)_2OH{\cdot}2H_2O\}$ and jahnsite $\{(Fe^{3+}{_{0.7}},Mn_{2.3})(PO_4)_2OH{\cdot}4H_2O\}$ by hydrothermal alteration. In particular, near fractures, the triplite has been separatelty replaced by the phosphosiderite ($Fe^{3+}PO_4{\cdot}2H_2O$) and Mn-oxide minerals during weathering stage.

• Microbiology and Biotechnology Letters
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• v.8 no.2
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• pp.119-123
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• 1980

Culture conditions of yellow pigment in Monascus sp. were studied. According to the studies of culture conditions optimum condition was found to be pH 4.5, 3 days of incubation with 3% of sucrose as carbon source, 0.2 ％ of yeast extract as nitrogen source and 75m1 of medium in the 500m1 erlenmyer flask by rotary shaking (rpm 180) at 180 r.p.m. Effective levels of inorganic compounds were found to be 0.25 % of potassium phosphate monobasic and 0.1 ％ of Magnesium sulfate.

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.15-19
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• 1974

A severe ginseng root rot disease was occurred and became widespraed in 1973 affecting the ginseng cultivating plot around Kangwha and Gimpo-Gun of Kyunggi province. Soil samples were collected from the area of Wolgot-Myun, Gimpo-Gun, Kuunggi-Do, 1974. We examined general fungi and Fusarium sp. in soil layers and also in different kinds of soil of respective diseased, uncultivated and healthy areas, and found the following results. 1. In the diseased and uncultivated area, the content of moisture, organic matter and silt was greater than in the healthy area. 2. Contray to the above, the healthy area contained a greater amount of inorganic elements such as $P_2O_5$, K,Ca and of soil particle such as Cs and Fs. The degree of pH and content of Mg were even in the three types of soils. 3. General fungi were found in abundance in the diseased and uncultivated soils. It was observed that in all types of areas, general fungi reside in abundance in the rhizosphere, i.e., 10-15cm layers and that the closer the surface, the greater the numbers of fungi. 4. A great number of Fusarium sp. was found in the uncultivated area, and followed diseased and healthy areas. It was observed that in all types of areas, Fusarium sp. distributed in abundance in rhizosphere and that the closer the surface, the greater the numbers of Fusarium sp., with the numbers decreasing as the soil layers increase.