• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.25-31
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• 1976

The purpose of this investigation is to find out the effects on the changes of microflora and the effects on the inorganic nutrients of the fertilized soil and the non-fertilized soil under submerged condition with the treatment of butachlor at the levels of 250, 500, and 1000ppm respectively. The survey was made within the period of 72 days with 7-day intervals under the incubated condition. The result came out to be the following: 1. The Fluctuated changes of soil microflora A. Bacteria: The plots treated by 500ppm of butachlor in case of non-fertilized soil showed the decreasing tendency of bacteria until 21st day. But there were no effects on the other plots. The plots treated by 250ppm and 500ppm in case of fertilized soil showed decreasing tendency on the 7th day, and 1000ppm until 21st days. B. Actinomycetes: There was no effects on the actinotnycetes in case of the non-fertilized soil but the fertilized soil showed some decrease. In both cases, actinomycetes have generally shown a little increase according to the time passage. C. Fungi: In both cases of the fertilized soil and the non-fertilized soil, the plots treated by the media showed some decreasing tendency in comparison with the control plots. There was no change to the number of fungi according to the time passage. 2. The fluctuated changes of nutrient A. $NH_4-N$: The whole plots showed decrease of $NH_4-N$ by adding butachlor. The higher the intencity of butachiar showed the more decreasing tendency of $NH_4-N$. In case of the non-fertilized soil, the highest increase of $NH_4-N$ appeared from the 7th day to 14th day, but showed degrease thereafter. The increasing tendency was seen in case of the fertilized soil plots. B. $NO_3-N$: Decrease of $NO_3-N$ was shown in the whole plots by the treatment of media, and on the 44th day of cultivation almost none of $NO_3-N$ was detected. C. $NO_2-N$: Whole plots showed the number of $NO_2-N$ highest on the 35th day, and there were nothing measurable on the 44th day. D. Eh: On the fertilized soil, the condition of reduction went on strongly but on the non-fertilized soil, the condition of reduction kept on till 42nd day and oxidation appeared thereafter.

• Korean Journal of Environmental Agriculture
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• v.17 no.3
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• pp.220-226
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• 1998

The effects of metalaxyl(granule), carbofuran(granule) and simazine(water soluble powder) on the soil microflora were conducted at field soil between Iksan and Chonju province. Pesticides were divided into 0.5, 1, 1.5 and 2.0 times of normal of field, respectively. The number of fluorescent Pseudomonas was ranged from $10^3$ to $10^6/g$ in both field soil treated with cabofuran. Pseudomonas concentration of Chonju field soil slowly increased and approached the maximum level at 56 day after treatment(DAT). It showed the higher at 14DAT than other DAT in Iksan field soil treated with metalaxyl or simazine, whereas it increased again at 112 DAT in metalaxyl treatment. Cabofuran treatment of both field soil showed maximum Pseudomonas number at 28 DAT compared to that of other treatments. In Chonju field soil, those Pseudomonads of metalaxyl and simazine treatment increased the highest level at 7 DAT. Simazine treatment decreased it's number from the beginning of experiment. In both soil, metalaxyl treatment decrease the general fungi number at 7 DAT, but increase at 14 and 56 DAT in Iksan field soil. However it increased at 56 DAT in Chonju field soil. Cabofuran treatment of Iksan field soil tended to decrease general fungi number at 28 DAT, but was ranged from 1.0 to $8.6{\times}104/g$ for the rest of experimental period. It started to increase at 56 DAT simazine treatment of Iksan. General bacterial concentration both soil treated with cabofuran was belong to $26.6{\sim}29.6{\times}106$. It was the highest at 56 DAT, but was not significantly different. General actinomyces number was highly increased at 7 and 112 DAT compared to that of other DAT. Pseudomonas putida or P. fluorescens from both field soil was separated and identified 10 to 30 of all 104 Pseudomonas, respectively. All isolated microorganisms showed chemical resistance of 100ppm metalaxyl, cabofuran and simazine treatment.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.55-64
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• 2003

It was investigated the possibility to use charcoal powder as beneficial soil conditioner, which used frequently in environmentally friendly agricultural farming system. For this purpose, the effects of charcoal powder on the growth of red pepper and chemical and microbiological properties of soil were also determined. The application of charcoal powder resulted in no significant differences of pH and EC in the soil compared to those of control. However, small particle size of charcoal powder increased yield of red pepper while large charcoal powder resulted in decrease of root growth of red pepper. Furthermore, the application of charcoal powder resulted in changes of soil microflora relating to plant growth stage. The number of the nitrogen fixing bacteria and fungi increased at the early growth stage, while phosphate releasing fungi in the soil increased at the late stage of growth by charcoal powder application. These beneficial effect of charcoal powder on the soil microbial properties was larger by the use of smaller particle size of charcoal powder. Therefore, it indicated that the small size of charcoal powder might be more influential on the red pepper yield and soil microbial properties may be due to large capacity of nutrients uptake for the plant and microorganisms. Additionally the optimal application amount of charcoal powder for the red pepper could be suggested as much as 300kg 10a$^{-1}$ for the both purposes of improvement of crop yield and retardation of the nutrients accumulation by excess charcoal application.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.303-311
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• 1996

The microflora changes of 10 water-controled treatments combined with livestock manures(pig, chicken) and bulking agents(sawdust, paper sludge) were investigated. The B/F values of the P-1 and C-1(65%, $H_2O$) treatments were 3571 and 5400 respectively, but those of the P-4 and C-4(50%, $H_2O$) treatments showed very low values, 667 and 334, respectively. The B/F values tended to increase with higher water content of the treatments. In the composting processes, the successions of microflora, adapting the compost environments, took place via fluctuating temperature. In the high temperature period, the numbers of mesophilic bacteria and fungi decreased, but that of the spore forming bacteria increased. However, the number of mesophilic bacteria inereased during the cold period. The B/F values of compost ranged 25-300, which indicates a decrease in the quantity of bacteria. The time required for the temperature of compost to reach $60^{\circ}C$ showed different patterns. There was no pathogenic microorganism in the treatments which reached a high temperature in a short period of time, but, in the treatments which reached a high temperature over a Long period of time, the pathgenic microorganism was not still alive.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.2
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• pp.82-89
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• 1984

These studies were carried out to investigate the effects of rice straw on microflora in relation to nitrogen metabolism in submerged soil. Rice plants were cultured in submerged soil to which rice straw was applied. In the submerged soil applied with rice straw the value of Eh lowered. pH was higher in the upper layer than in the lower. The content of iron(II) in submerged soil increased, while that of ammonium nitrogen decreased when rice straw was applied and nitrate-nitrogen was hardly detected during the rice cultivation period Under application of rice straw the number of denitrifying bacteria observed to increase at the early growing stage of rice plant and to decrease thereafter, and that of nitrate reducing bacteria increased at the late growing stage. The number of ammonium oxidizing bacteria and that of nitrite oxidizing bacteria decreased continually but the latter were rather sharply decreased.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.3
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• pp.297-302
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• 1996

The effect of application rate of pig or chicken manure on the seasonal change of tomato(Minicarol) rhizosphere microflora was investigated by field experiment were surface soil(16cm) mixed with manures 1 weeks before transplanting. 1. Rhizobacteria population of control plot decreased 5 weeks after transplanting(WAT) than 1 WAT and 1.5~2 times higher colony counting was found in DNB(Diluted nutrient broth medium) than NB(Nutrient broth medium) at 15 WAT. 2. Rhizobacteria population at 1 WAT inereased in NB medium with the application rate of both manures but decreased in DNB with chicken manure. Colony counting in NB of 60 and 120 mg/ha treatment was 100 times higher than that of the control. However, rhizobacteria in DNB at 15 WAT(harvest stage) was much higher than that of NB. 3. Application rate did not affect fungi population 1 WAT in pig manure but decresed in chicken manure. At 15 WAT fungi population was 2 times higher than 1 WAT with chieken manure and highest in 30 mg/ha but with pig manure decreased with rate than the control. 4. Actinomycetes population at 1WAT was not different among pig manure rates and decreased with chicken manure than control. At 15 WAT population increased in all manure rates. especially in 10 mg/ha pig manure and 30 mg/ha chicken manure 4 times that 1 WAT.

• Journal of Ginseng Research
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• v.21 no.2
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• pp.91-97
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• 1997

In order to elucidate the mechanism of red-colored phenomena(RCP) in ginseng(Panax ginseng C.A. Meyer), distribution of inorganic elements of ginseng root and its surrounding soil, and microflora in the soil were investigated. Red brown colored-substances were accumulated in the cell wall of epidermis at early stage of red-colored ginseng (RCG). Cell wall of the late stage of RCG was disordered and microorganisms were shown in the disordered cell wall. Al, Si and Fe contents among inorpanic elements in the epidermis of RCG were higher at two or three times than that of healthy ginseng. On the other hand, K content was higher at three times in healthy ginseng than that of RCG. Especially, Fe content was higher at three times in lateral roots of RCG than that of healthy ginseng. Total 21 strains of microorganisms were isolated on the 523 medium from surface soil, surrounding soil of both healthy and RCG, and RCG. Six strains of microorganisms among them were resistant to 2 mM Fe. Two species in Bacillus app. and Lactobacillus app. , and one species in Micrococcus sp. and Npisseria sp. respectively were identified. It seemed that RCP was closely related with the distribution and uptake of inorganic elements, was also correlated Fe-independent metabolism of microorganisms.

• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.61-65
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• 2000

Effects of temperature, soil moisture level, flooding, and soil microflora on decay of root galls in club root disease of Chinese cabbage were examined in the laboratory. Number of days required for complete decay of root galls was 3 days at $32^{\circ}C$ or higher, 12 days at $16{\sim}20^{\circ}C$ and 28 days at $8^{\circ}C$. As soil moisture content goes up, root gall decay became faster resulting 3 days for complete decay under saturated moisture condition at high temperature of $32^{\circ}C$, and 8 days under the same moisture level at $24^{\circ}C$. Soil moisture effect was relatively low at $24^{\circ}C$ compared to $32^{\circ}C$. Stimulation of decay by soil flooding was not observed at $32^{\circ}C$ but became apparent at $12^{\circ}C$. Influence of soil microflora on root gall decay was negligiable. Based on these results, temperature appears to be the most important factor affecting root gall decay in soil. Root gall decay is thought to be affected more easily by other environmental factors under low temperature conditions. Maturity of resting spores of Plasmodioprora brassicae in root galls tended to increase as time prolongs during root gall decay. Density of the resting spores was lower in fresh root galls where their maturity was also low as compared to completely decayed root galls. Number of resting spores in completely decayed root gall was $6.5{\times}10^{6}/g$ tissue and its maturity was over 95%.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.257-266
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• 2002

The purpose of this study is screening of microfloras involved in hydrolysis of seaweed tenella, seaweed fusiforme and green laver. This is a part of studies on the hydrolysis of seaweed using microorganisms. First, about two hundred microflora samples were obtained from mountain, rice field, dry field, sea, seaside and fish market in the vicinity of Yeosu. Thirty-three microflora samples were screened from the destruction of tissue in sea tangle and sea mustard. It was sufficient that results of the naked eye observation were obtained at eight microflora samples as a feces of bull, a decayed pine tree, a soil of dry field, the mud of the banks in a rice field, the water of a ditch in a rice field, the weed of the banks in a rice field, the water in a rice field and leaved in the air. Above all, extraction rate and contents of reducing sugar in extracts of seaweeds added a decayed pine tree(sample No. 8) and the water of a ditch in a rice field(sample No. 27) were showed high value. And the value of chemical analysis of the sample is much better in comparison with control. Accordingly the hydrolysis of seaweed using microorganisms in the inside of these microflora samples can be possible.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.289-298
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• 1984

These studies were carried out to investigate the effects of rice straw on microflora in relation to the decomposition of organic matter, and the rate of rice straw decomposition. The number of total bacteria was increased in the first stage, and the number of microorganisms in upper layer was generally larger than lower layer. The number of fungi tended to decline as rice plant grew. Aerobacter among cellulose decomposition bacteria decreased with time, and the number of microorganisms in lower layer was higher than upper layer. The number of glucose decomposition bacteria and sulfate reducing bacteria increased in the submerged soil to which rice straw was applied, but decreased by percolation. the change of manganese oxidizing bacteria seemed not to be affected by rice straw application while they tend to increase as the rice plant grew. The aspect of microorganisms in the percolated water was same that of lower layer, but the number was low as much $10^{-1}$ during the whole stages. The decomposition rate of rice straw applied to submerged soil was about 40 per cent during the rice grew. The decomposition rate of cellulose contained rice straw was about 30 per cent, and lignin was about 60 per cent. The 70-80 per cent of nitrogen remained in the rice straw applied to soil.