• 한국미생물·생명공학회지
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• 제28권4호
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• pp.239-241
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• 2000

From 5 forest soil samples, the isolation frequency of oligotrophic Actinomycetes was investigated with nutrient and minimal media. The frequency of soil Actinomycetes by the minimal media. The frequency of soil Actinomycetes by the minimal media of DHV, WA, BA and NA was similar to the value by HV nutrient medium. In addition, different Actinomycetes were isolated from all the media used in this experiment and then their growth were tested on nutrient (Bennett's agar) and minimal media(WA). In consequent, the number of different Actinomycetes from minimal media was 26.1 strains, whereas the number of from nutrient medium (HV) was 26.6 strains. Furthermore, the percentage of facultative and obligate strains among the oligotrophic Actinomycetes was 90% and 10%, respectively.

• 한국미생물·생명공학회지
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• 제28권3호
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• pp.129-133
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• 2000

Different actinomycete strains were isolated from natural lime caves of Ondal Chemongok Hwanseon and Yongyeon which are located at Kangwon or chungcheongbook province in Korea and were identified to the genus level. Soil sam-ples were collected at 6 sites inside and 2 sites outside of each natural lime cave, As the result the strains belonging to genus Streptomyces and rare actinomycetes were isolated at the average of 2.1 and 3.4 strains per g soil on inside cave whereas which were isolated at the 6.0 and 1.8 strains per g soil on outside cave. How-ever the generic distribution of Streptomyces and rare actinomycetes isolated from outside cave was quite dif-ferent from that of inside cave. It was shown that rare actinomycetes at natural lime caves is generally highly abundant than Streptomyces.

• 한국미생물·생명공학회지
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• 제23권1호
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• pp.36-42
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• 1995

Actinomycetes occur in a wide range of environments and many more actinomycetes remain to be detected in the natural environment. In isolation stages, selection of the environment as a source of useful isolates is important. Two hundred and eighteen strains were isolated on Bennet's agar and 346 strains were on humic acid-vitamin agar from five each paddy field, field, forest, grass land, riverside soil samples. These isolates were identified to the genus level based on morphological and physiological characteristics. Among them, 386 strains were Streptomyces, 49 strain were Nocardia, 35 strains were Microbispora and Micromonospora each, 15 strains were Nocardiopsis, 13 strains were Actinomadura, 10 strains were Streptosporangium, and the others were isolated rarely. According to soil type, Nocardia, Micromonospora, Microbispora and Streptosporangium were dominant in paddy field, Microbispora Nocardia, Nocardioides and Micromonospora were dominant in field, Nocardia, Micromonospora, Microbispora and Actinomadura were dominant in grass land, Nocardia, Micromonospora and Microbispora were dominant in forest, Nocardia, Microbispora and Micromonospora were dominant in riverside. Generally, Nocardia, Micromonospora, Microbispora and Actinomadura were isolated in all kinds of soils, Streptosporangium were paddy field, Dactylosporangium were forest, Nocardiopsis were field, forest and riverside.

• 한국토양비료학회지
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• 제49권5호
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• pp.480-488
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• 2016

Soil microbes are widely well known to play an important role for sustainable agriculture in terms of crop healthy cultivation and environmental conservation. In this context, the distributional characteristics of soil microbes according to cropping systems were investigated under rice (R)-rice (R), rice (R)-barley (B)-rice (R), and soybean (S)-barley (B)-soybean (S) cropping condition to get basic informations for sustainable agriculture, where barley was grown for winter, in mid-mountainous loam paddy located at the altitude of 285 m above sea level in Sangju area from 2014 to 2015. Estimating from microbial communities by fatty acid methyl ester (FAME) method, a total biomass of bacteria, actinomycetes, and fungi in R-B-R plot was 37% and 40% higher than that in S-B-S and R-R plots, respectively (p < 0.05). In especial, bacteria and fungi were more in R-B-R plot than those in any other ones. B. japonicum, AMF, and mesophilic Bacillus sp. were also greater in S-B-S plot than those. In the community distribution, however, bacteria and actinomycetes showed comparatively high values in S-B-S plot relative to either R-R or R-B-R plot including rice, in which fungi outstanding. In the correlation between microbial biomass and soil properties changed by the cropping, bacteria was positively correlated with C:N ratio; actinomycetes with exchangeable Ca; fungi with available $P_2O_5$ (p < 0.05). While these microbes showed negative response to water stable aggregates of soil.

• 미생물학회지
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• 제34권3호
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• pp.149-153
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• 1998

산림, 밭, 초지, 논 토양의 두 깊이(0~2cm, $50{\pm}1cm$)에서 계절별로 채취한 토양 시료로부터 서로 다른 방선균주를 분리, 동정하여 계절별 토양 방선균의 속 다양성을 조사하였다. 토양 표층에 분포하는 Streptomyces속 방선균주의 계절별 변동율은 논(18%)과 산림(18%) 토양에 비해 초지(41%)와 밭(39%) 토양에서 더 높게 나타났으며 $50{\pm}1cm$깊이에서는 논(36%), 밭(28%), 초지(26%), 산림(16%) 토양 순으로 높게 나타났다. 한편 희소 방선균의 계절별 분포 변동율을 토양 표층의 경우 논 토양(26%)을 제외하고는 모두 45%이상이었으나 $50{\pm}1cm$깊이에서는 산림(79%), 논(36%), 밭(24%), 초지(10%) 토양 순으로 높게 나타났다. 따라서, 토양 중에 분포하는 방선균의 속 다양성은 계절 변화에 의지하며 또한 이는 방선균군의 종류, 토양의 유형, 그리고 토양 깊이에 의해서 영향을 받을 것으로 고려된다.

• 미생물학회지
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• 제34권3호
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• pp.144-148
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• 1998

공시 토양의 0.5~2 cm, $10{\pm}1cm$, $50{\pm}1cm$깊이에서 계절에 따라 토양 시료를 채취한 후 희석 평판법을 이용하여 세균, 곰팡이, 방선균의 분리 빈도를 측정하였다. 이 결과들을 근거로 토양 미생물의 밀도(집락수/g 건조 토양)와 상대적 분포율(%)을 조사하여 계절 변화에 따른 미생물들의 분포 변동을 분석하였다. 계절에 따른 토양 미생물들의 밀도 변화에서, 세균(24배)과 방선균(7배)은 $50{\pm}1cm$깊이에서 가장 큰 변동을 나타내었고 곰팡이는 $10{\pm}1cm$깊이에서 가장 큰 변동(13배)을 나타내었다. 또한 전반적으로 세균은 봄에, 곰팡이는 겨울에, 방선균은 가을에 높은 토양밀도를 나타내었다. 한편 계절에 따른 토양 미생물들간의 상호 분포율 변화에서, 세균은 봄에 $50{\pm}1cm$깊이에서 상당히 높은 분포율(85.7%)을 나타내는 반면 여름에 $10{\pm}1cm$깊이에서는 낮은 분포율(35.2%)을 나타내었다. 곰팡이의 분포율은 겨울에 $50{\pm}1cm$깊이에서 크게 증가한 (23.0%) 반면 봄에 $10{\pm}1cm$깊이에서는 극히 낮은 분포율(0.5%)을 나타내었다. 방선균은 겨울에 $10{\pm}1cm$깊이에서 높은 분포율(45.2%)을 나타내는 반면 봄에 $50{\pm}1cm$깊이에서는 낮은 분포율(12.2%)을 나타내었다.

• 미생물학회지
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• 제52권1호
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• pp.59-64
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• 2016

본 연구에서는 차세대 염기서열분석(pyrosequencing) 기술을 이용해 조릿대(Sasa borealis) 대나무림의 낙엽층과 근권 토양 내 주요 군집인 방선균군집의 계통학적 특성을 분석하여 방선균 유전자원 다양성 확보를 위한 기반 연구를 수행하고자 하였다. 낙엽층 시료 내 세균군집은 2,588 OTUs, 다양성 지수 7.55로 나타났으며, 근권토양 시료의 경우 2,868 OTUs, 다양성 지수 8.15로 다양한 세균군집이 균등하게 분포하고 있는 것으로 확인되었다. 대나무림 토양시료 내 세균군집은 총 35개의 문으로 구성되었으며, Proteobacteria (51-60%), Bacteroidetes (16-20%), Acidobacteria (4-16%) 그리고 Actinobacteria (4-14%) 계통군이 주요 세균군집으로 확인되었다. 특히, Actinobacteria은 총 6목 35과 121속의 다양한 방선균이 분포하였으며, 전체 방선균군집의 83%가 Actinomycetales 목으로 확인되었다. 이들 Actinomycetales 목은 28개 과로 구성되었으며, Micromonosporaceae, Pseudonocardiaceae 그리고 Streptomycetaceae는 조릿대 대나무림의 낙엽층과 근권토양에서 풍부도가 가장 높고 변이가 적은 대표 방선균군집으로 확인되었다.

• 한국미생물·생명공학회지
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• 제27권6호
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• pp.515-517
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• 1999

From the soils collected seasonally at the 0.5~2cm and 50$\pm$1cm depths of riverside, different strains of actinomycetes were isolated and identified to the genus. At the 0.5~2cm depth, Streptomyces and rare actinomycetes were in total 73 and 62 strains, respectively. Streptomyces was approximately 2-fold more in spring and autumn than summer, and rare actinomycetes was at least 4-fold more in autumn and winter than spring. At the 50$\pm$1cm depth, Streptomyces and rare actinomycetes were in total isolated 53 and 41 strains, and these were at least 2-fold more diverse in autumn than spring, summer, and winter.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.703-712
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• 1998

Physicochemical factors, microbial population size and the properties of the bacterial isolates were estimated to find out the nature of soil ecosystem of Mt. Nam. Samples were obtained from the surface layer of soils on which specific plant community is developed. Average content of moisture and organic matter of the soils were 21.6% and 17.3%, respectively. These values were similar to those of developing forest soils, but were slightly lower than those of climax ecosystem such as Piagol in Mt. Chiri. Chiri. Content of phosphate was higher than those of other forest soils. The population size of soil bacteria ranged from 27.4 to 195.8 ${\times}\;10^5$ CFU/g. duy soil, and the size is somewhat dependent on the moisture and oranic matter content of soils. A large number of bacteria were able to decompose macromolecules such as starch, elastin and gelatin. Bacterial species composition of each soil was comparatively simple. Pseudomonas, Agrobacterium, Flavobacterium and Xanthomonas which are Gram-negative short rods were widely distributed in the forest soils. The endospore forming Bacillus species were also the main constituents of the soil microflroa. Actinomycetes were widely distributed in the forest soils, but the distribution pattern varied in each site. Most of the actinomycetes were also able to decompose organic macromolecules. The rate of resistant actinomycete strains to antibiotics and heavy metals were lower than those from cultivated soils, but higher than those from well-preserved forest soils. Antibiosis pattern of the actinomycete isolates was similiar to the resistance pattern. This means the forest soils of Mt. nam was somewhat interferred by artificial behabiour.

• The Korean Journal of Ecology
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• 제9권1호
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• pp.9-18
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• 1986

The decomposition of litters of Pinus densiflora and the growth of microbial populations in a calcareous region, Youngwal were compared with those in a noncalcareous region, Sinlim. The decay rate of litter in Pinus densiflora in Youngwal was 0.128 and that in Sinlim was 0.096. The differences in the populations of soil bacteria and total microorganisms between the two regions were signficant at the 5% level, but that of fungi and actinomycetes was not at that level. The differences in the content of calcium and pH value of soil between the two regions were significant at the 1% level. The excessive content of calcium became to increase pH value, in turn the high pH decreased the content of available phosphorus in soil. The vertical distribution of the content of available phsophorus was consistent with that of the populations of fungi and actinomycetes in Youngwal.