• The Korean Journal of Mycology
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• v.42 no.1
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• pp.34-39
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• 2014

In this study, the community structures of arbuscular mycorrhizal fungi (AMF) in rhizospheres of Camellia japonica and neighboring woody plants in Wando, Korea were investigated. Rhizospheres of C. japonica and other woody plants were dominated by the same species, Acaulospora mellea, but Shannon's index, species richness and total spore numbers of the AMF communities were higher in non-C. japonica than in neighboring plants. Regardless of host plant species, the frequency of A. mellea was significantly high comparing with other AMF species. The community similarity of AMF within C. japonica was significantly higher than between C. japonica and neighboring plants or neighboring plants (p<0.005). Results showed that AM fungal communities in rhizospheres of C. japonica have unique community structure and are different from that of neighboring host plants, suggesting that community structure of AMF could be influenced by host plant species.

• 농업기술회보
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• v.51 no.5
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• pp.17-18
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• 2014

최근 들어 식물의 뿌리 주변에는 사는 근권미생물과 식물과의 상호작용연구가 새롭게 조명되고 있다. 바실러스, 슈도모나스 등의 근권미생물은 식물의 면역기능을 활성화시켜 작물의 건강을 지키는 것으로 밝혀지고 있으며 이러한 기술을 도입할 경우 농작물의 안전 관리에 중요한 역할을 한다.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.10a
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• pp.142-145
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• 1998

근권용량을 2, 4, 6, 8 및 10$\ell$로 제한하여 펄라이트를 채워 오이를 재배한 결과 근권용적이 증가할수록 초장, 경경, 엽수 및 엽면적이 증가하였고, 과실수와 과실중량에서는 근권용적이 큰 8$\ell$와 10$\ell$의 처리구에서 가장 양호하였으며 기형과 발생률도 낮은 경향이었다. 근권용적 6$\ell$를 기준으로 미만의 처리구에 비해 이상의 처리구에서 경으로의 건물분배가 줄어들고 엽으로의 건물분배가 많은 것을 볼 수 있었다.

• Journal of Bio-Environment Control
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• v.8 no.1
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• pp.36-41
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• 1999

This study was carried out to investigate the effect of root zone restriction on yield and quality of muskmelon. Three cultivation methods, isolated bench, root zone restriction sheet(RZR sheet) and conventional soil culture, were compared from April 19th to July 17th. Soil temperature was higher at isolated bench and the growth of melon was accelerated at isolated bench compared to soil culture or RZR sheet. Fruit size was bigger in order of soil culture, isolated bench and RZR sheet, while sugar content and net shape were greatest at isolated bench, and the percentage of wilted plant was 3.3% at isolated bench, 25.0% at RZR sheet and 26.7% at soil culture. Therefore, marketable yield was higher at isolated bench compared to conventional soil culture.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.783-789
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• 2010

The effective method for heating root-zone during winter season was studied in the aspects of growth, yield and economics for tomato ($Solanum$ $lycopersicum$) in perlite bag culture. There were four root-zone heating treatments: two hours heating from one hour before to one hour after sunrise, four hours from two hours before to two hours after sunrise, 15 hours after sunset, and no heating. The growth characteristics of the upper parts of plants were not significantly different among the treatments, but root volume increased with longer heating of the root zone. The Plant Development Index, using stem diameter and the length between growing tip and the upper flowering truss, showed relation between yield per cluster and growth pattern. The treatment heating for four hours was the most economic in terms of growth and yield of tomato.

• The Korean Journal of Mycology
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• v.44 no.2
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• pp.82-86
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• 2016

In this study, we investigated the spore diversity of arbuscular mycorrhizal fungi (AMF) in rhizospheres of a post-mining area and a natural forest area in Jecheon, Korea. The rhizospheres of the post-mining areas were dominated by Acaulospora mellea, while those of the natural forest area were dominated by Ambispora leptoticha. The number of AMF spores in rhizospheres of the post-mining area was significantly higher than that in the rhizospheres of the natural forest area. Although the diversity index of each area showed no significant difference, the community similarity of AMF within the rhizospheres of natural forest area was significantly higher than that observed within those of post-mining area. These results showed that AM fungal communities in rhizospheres could change because of the degree of disturbance.

• Research in Plant Disease
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• v.16 no.1
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• pp.35-40
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• 2010

Suppression effect of the 12 bacterial isolates from plant rhizosphere against late blight caused by Phytophthora citrophthora were investigated on citrus fruits. Among the bacterial isolates, THJ609-3, TRH423-3, BRH433-2, Lyso-chit and KRY505-3 presented disease suppression after wound inoculation with the fungal pathogen in vivo. The anti-fungal activity was evaluated by measuring the length of inhibition zone of the mycelium P. citrophthora adjacent to the effective bacterial isolates in which all of the 5 bacterial isolates showed antagonistic effects. However, there was no positive correlations between the efficacy of disease suppression and the antagonistic effect. On the other hand, Lyso-chit and KRY505-3 were identified as Bacillus cereus, BRH433-2 as B. circulans and TRH423-3 as Burkholderia gladioli, respectively, by analysis of rDNA sequence on the internal transcript spaces. It is suggested that the effective bacterial isolates may be useful for finding biological control agents against late blight especially on environment-friendly farm where the application of fungicide is limited.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.7-11
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• 1999

The measurement of pH in the rhizosphere soil was conducted to clarify whether the growth of pokeberry plants affect the acidity of rhizosphere soil in two environmentally contrasting area Ulsan and Chongju city. The rhizosphere pH between 5.25 and 5.33 was shown in the pokeberry stand at Mt. Boomo located at Chongju. The rhizosphere pH of pokeberry stands at Mt. Bongdae, Mt. Sinsun and Mt. Totchil was below 5.0, and did not differ with depth and distance from the main axis of root. At Mt. Bongdae, however, the pH in the rhizosphere soil was significantly changed with soil depths though that was not changed horizontally. The rhizosphere pH at top soil was lower than that at subsoil, which indicates the fact that soil acidification at Mt. Bongdae was not caused by pokeberry plants. Furthermore, the rhizosphere pH did not change with the growth of pokeberry plants. These results indicate that the hypothesis that pokeberry plants acidify local soil environment should be reconsidered.

• Journal of Bio-Environment Control
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• v.4 no.2
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• pp.152-158
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• 1995

This experiment was undertaken in order to clarify effect of NO$_3$-N/NH$_4$-N ratios(NO$_3$/NH$_4$ : 10:0, 8:2) in the nutrient solution on growth, yield, photosynthetic rate, relative concentration of chlorophyll and root activity of hydroponically grown pepper plants at three different root- zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$. Plant height, leaf number, stem diameter, fresh and dry weight of leaf and root were no effect in by three root- zone temperatures. However, leaf number, stem diameter, fresh and dry weight of leaf and stem, dry weight of root at 18$^{\circ}C$, 22$^{\circ}C$ and $25^{\circ}C$ increased when NH$_4$-N was added to the solution. Under root-Bone temperatures of 18$^{\circ}C$, 26$^{\circ}C$ condition, fruit length were longer by the addition of NH$_4$-N. Fruit number and yield increased by the addition of NH$_4$-N at three root-zone temperatures. Photosynthetic rate decreased as root - zone temperature increased. Under root-zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, photosynthetic rate increased significantly by the addition of NH$_4$-N. Chlorophyll content of plants increased at 22$^{\circ}C$. Under root-zone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, chlorophyll content of plants increased by the addition of NH$_4$-N. Root activity of increased at 26$^{\circ}C$ Under root-Bone temperatures of 18$^{\circ}C$, 22$^{\circ}C$ and 26$^{\circ}C$ condition, root activity increased by the addition of NH$_4$- N.

• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.466-472
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• 2011

BACKGROUND: Soybean [Glycine max (L.) Merrill] is a legume and an important oil crop worldwide. This study was conducted to evaluate the possible impact of transgenic soybean cultivation on the soil microbial community. METHODS AND RESULTS: Microorganisms were isolated from the rhizosphere soils. Microbial community was identified based on the culture-dependent and molecular biology methods. The total numbers of bacteria, fungi, and actinomycete in the rhizosphere soils cultivated with transgenic and non-transgenic soybeans were similar to each other, and there was no significant difference between transgenic and non-transgenic soybeans. Dominant bacterial phyla in the rhizosphere soils cultivated with transgenic or non-transgenic soybeans were Actinobacteria, Firmicutes, and Proteobacteria. The microbial communities in transgenic and non-transgenic soybean soils were characterized using the denaturing gradient gel electrophoresis (DGGE). The DGGE profiles showed the different patterns, but didn't show significant difference to each other at 0.05 significance level. DNAs were isolated from soils cultivating transgenic or non-transgenic soybeans and analyzed for persistence of transgenes in the soil by using PCR. PCR analysis revealed that there were no amplified ${\gamma}$-tmt and bar gene in soil DNA. CONCLUSION(S): The results of this study suggested that microbial community of soybean field were not significantly affected by cultivation of the transgenic soybeans.