• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.121-126
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• 2000

Composition of fungal communities in three microhabitats such as soil, rhizosphere and rhizoplane were studied to understand the root environment of healthy and diseased plants in Phytophthora non-infested and infested fields, respectively. Samples were collected from the tomato- and red pepper-growing greenhouses in Kyungsang-Nam Province on April, 1999. Twenty-five species were isolated from each vegetation field using the dilution plate technique. There were a greater variety of species in infested fields than non-infested and in soils than in both rhizospheres and rhizoplanes. The number of species isolated were varied amongst the different microhabitats. A Trichoderma species was isolated only from non-infested fields.

• Horticultural Science & Technology
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• v.28 no.3
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• pp.476-483
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• 2010

Total bacterial populations were cultured from the Hydroball cultivation media in the rhizospheres of 9 different plants including $Hedera$ $helix$ L. and $Dracaena$ $deremensis$ cv. Warneckii Compacta, etc. These cultured bacterial populations were studied to test if the bacterial populations in the plant growing pots may play a role on removal of volatile organic compounds (VOCs) such as benzene and toluene in the air. To meet this objective, first, we tested the possibility of removal of VOCs by the cultured total bacteria alone. The residual rates of benzene by the inoculation of total bacterial populations from the different plant growth media were significantly different, ranging from 0.741-1.000 of $Spathiphyllum$ $wallisii$ 'Regal', $Pachira$ $aquatica$, $Ficus$ $elastica$, $Dieffenbachia$ sp. 'Marrianne' Hort., $Chamaedorea$ $elegans$, compared to the control with residual rate of 0.596 (LSD, $P$=0.05). This trend was also similar with toluene, depending on different plants. Based on these results, we inoculated the bacterial population cultured from $P.$ $aquatica$ into the plant-growing pots of $P.$ $aquatica$, $F.$ $elastica$, and $S.$ $podophyllum$ inside the chamber followed by the VOCs injection. The inoculated bacteria had significant effect on the removal of benzene and toluene, compared to the removal efficacy by the plants without inoculation, indicating that microbes in the rhizosphere could play a significant role on the removal of VOCs along with plants.

• Microbiology and Biotechnology Letters
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• v.49 no.3
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• pp.413-424
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• 2021

In order to enhance rhizoremediation performance, which remediates contaminated soils using the interactions between plants and microorganisms in rhizosphere, it is required to develop effective microbial resources that simultaneously degrade contaminants and promote plant growth. In this study, heavy metal-resistant rhizobacteria, which had been cultivated in soils contaminated with heavy metals (copper, cadmium, and lead) and diesel were isolated from rhizospheres of maize and tall fescue. After that, the isolates were qualitatively evaluated for plant growth promoting (PGP) activities, heavy metal tolerance, and diesel degradability. As a result, six strains with heavy metal tolerance, PGP activities, and diesel degradability were isolated. Strains CuM5 and CdM2 were isolated from the rhizosphere soils of maize, and were identified as belonging to the genus Cupriavidus. From the rhizosphere soils of tall fescue, strains CuT6, CdT2, CdT5, and PbT3 were isolated and were identified as Fulvimonas soli, Cupriavidus sp., Novosphingobium sp., and Bacillus sp., respectively. Cupriavidus sp. CuM5 and CdM2 showed a low heavy metal tolerance and diesel degradability, but exhibited an excellent PGP ability. Among the six isolates, Cupriavidus sp. CdT2 and Bacillus sp. PbT3 showed the best diesel degradability. Additionally, Bacillus sp. PbT3 also exhibited excellent heavy metal tolerance and PGP abilities. These results indicate that the isolates can be used as promising microbial resources to promote plant growth and restore soils with contaminated heavy metals and diesel.

• The Korean Journal of Mycology
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• v.22 no.4
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• pp.394-409
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• 1994

The symbiotic activities of arbuscular mycorrhizal fungi(AMF) such as spore density, symbiotic intensity and vesicle density, phytomasses of higher plants such as Calamagrostis epigeios, Imperata cylindria, Artemisia scoparia, Aster tripolium and Sonchus brachyotus and seasonal change of the AMF activities, electric conductivity and zinc contents in plant and soil were determined in the rhizospheres of higher plants at abandoned old coastal reclaimed lands, where constructed in 12 and 30 years ago. If plants of reclaimed land classified to salinity, symbiotic activities of AMF were high in order of obligate halophyte, facultative halophyte and glycophyte. Also, those plants classified to life form, symbiotic activities of AMF were high in order of annual, biennial and perennial plants. Seasonal variation of spore density, one of symbiotic activities showed that the plateau density maintained continuously from the end of growing season of the higher plants to next spring. For this reason, it regarded that reproduction of AMF spore would be formed in autumn, when the higher plants will be developed. Seasonal change of symbiosis intensity, other symbiotic activities, however, showed that the highest symbiosis intensity occurred in spring and summer but the lowest in autumn. In relationships among symbiotic activities, spore density was directry proportional increase of symbiosis intensity. Moreover, phytomass of higher plants also was directly proportional to increase the spore density as well as symbiosis intensity. Vesicle density, however, did not any correlation with the phytomass, spore density and symbiosis intensity. From these results, it can know that both spore density and symbiosis intensity are strongly possible to use as the measure of symbiotic activity owing to symbiosis of tho-AMF, the more absorption of zinc by the higher plants carried out the less concentration of zinc in the soil.

• Journal of Life Science
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• v.25 no.2
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• pp.189-196
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• 2015

Bacterial diversity was studied in the rhizosphere of Suaeda japonica Makino, which is native to Suncheon Bay in South Korea. Soil samples from several sites were diluted serially, and pure isolation was performed by subculture using marine agar and tryptic soy agar media. Genomic DNA was extracted from 29 pure, isolated bacterial strains, after which their 16S rDNA sequences were amplified and analyzed. Phylogenetic analysis was performed to confirm their genetic relationship. The 29 bacterial strains were classified into five groups: phylum Firmicutes (44.8%), Gamma proteobacteria group (27.6%), Alpha proteobacteria group (10.3%), phylum Bacteriodetes (10.3%), and phylum Actinobacteria (6.8%). The most widely distributed genera were Bacillus (phylum Firmicutes), and Marinobacterium, Halomonas, and Vibrio (Gamma proteobacteria group). To confirm the bacterial diversity in rhizospheres of S. japonica, the diversity index was used at the genus level. The results show that bacterial diversity differed at each of the sampling sites. These 29 bacterial strains are thought to play a major role in material cycling at Suncheon Bay, in overcoming the sea/mud flat-specific environmental stress. Furthermore, some strains are assumed to be involved in a positive interaction with the halophyte S. japonica, as rhizospheric flora, with induction of growth promotion and plant defense mechanism.

• Journal of Life Science
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• v.24 no.4
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• pp.461-466
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• 2014

Three plant species, Aster sphathulifolius, Sedum oryzifolium, and Lysimachia mauritiana, native to the Dokdo Islands in South Korea, were examined for rhizosphere microorganisms by using 16S rDNA sequences. Nine species of rhizosphere microorganisms were isolated from the three native plant species, respectively. Phylogenetic analysis showed that the microorganisms could be classified into 19 species belonging to four phyla (Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria), and the characteristics of the microbes were confirmed. Rhizosphere microorganisms from the six orders (Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, Oceanospirillales, and Rhodobacterales) were isolated from S. oryzifolium. From L. mauritiana, microbes belonging to the seven orders (Bacillales, Flavobacteriales, Micrococcales, Oceanospirillales, Rhizobiales, and Rhodobacterales) were isolated. From A. sphathulifolius, the six orders of rhizosphere microorganisms (Alteromonadales, Bacillales, Corynebacteriales, Flavobacteriales, Micrococcales, and Rhizobiales) were isolated. These data showed that Actinobacteria and Proteobacteria were the dominant phyla for the rhizosphere of all three plants. To confirm the bacterial diversity in rhizospheres, Shannon's diversity index (H') was used at the genus level. In these data, the rhizosphere from S. oryzifolium and L. mauritiana had more diverse bacteria compared to that from A. sphathulifolius.