• Research in Plant Disease
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• v.12 no.2
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• pp.81-84
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• 2006

Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP were formulated as antagonists of Sclerotium cepivorum and Sclerotium sp. of garlic white rot. In the field test, applications of Trichoderma harzianum WP and Bacillus subtilis WP reduced garlic white rot by Sclerotium cepivrum from 10.9% in the control to 4.1% and 6.2%, respectively at Taean. Also at Seosan, applications of Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP reduced garlic white rot by Sclerotium sp. from 17.8% in the control to 1.2% and 2.6%, respectively. Treatment of Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP increased garlic yield in two area. Therefore, Trichoderma harzianum 23 WP and Bacillus subtilis 122 WP have shown potential as biofungicides of garlic white rot in the two different pathogens.

• Asian Journal of Turfgrass Science
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• v.20 no.2
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• pp.191-201
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• 2006

Dollar spot caused by Sclerotinia homeocarpa is one of major diseases in putting greens. Microorganisms antagonistic to S. homeocarpa, a pathogen of dollar spot, were primarily screened through in vitro tests, including dual culture method and triple layer agar diffusion method. In vivo tests were also conducted to select the best candidate for a biocontrol microorganism, using pot experiment. Bacillus subtilis EW42-1 and Trichoderma harziaum GBF-0208 were finally selected as biocontrol agents against dollar spot. Relative Performance Index(RPI) was used as a criterion of selecting potential biocontrol agents. B. subtilis EW42-1 and T. harzianum GBF-0208 showed resistance to several agrochemicals mainly used in a golf course. B. subtilis EW42-1 and T. harzianum GBF-0208 suppressed effectively the disease progress of dollar spot like synthetic fungicide tebuconazole in the nursery where dollar spot had seriously occurred. B. subtilis EW42-1 and T. harzianum GBF-0208 have a potential to be biocontrol agents for the control of dollar spot.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.1
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• pp.26-31
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• 2006

The saccharogenic liquid (SFW) obtained by the enzymatic saccharification of food wastes was used as a medium for production of bacterial cellulose (BC). The enzymatic saccharification of food wastes was carried out by the cultivation supernatant of Trichoderma harziaum FJ1 culture. Acetobacter xylinum KJ1 was employed for the BC production culture. The physical properties, such as polymerization, crystallinity, Young's modulus, and tensile strength, of BCs produced by three culture methods: the static cultures using HS (Hestrin-Schramm) as a reference medium (A) or the SFW medium (B), the shaking culture (C) or the air circulation culture (D) using the SFW medium, were investigated. The degrees of polymerization of BCs produced under the different culture conditions (A-D) showed 11000, 9500, 8500, and 9200, respectively. Young's modulus was 4.15, 5.0, 4.0, and 4.6 GPa, respectively. Tensile strength was 124, 200, 80, and 184 MPa, respectively. All of the BC had a form of cellulose I representing pure cellulose. In the case of the shaking culture, the degree of crystallinity was 51.2%, the lowest degree. Under the other culturing conditions, the trend should remain in the range of 89.7-84%. Overall, the physical properties of BC produced from SFW were similar to those of BC from HS medium, a commercial complex medium, and BC production by the air circulation culture mode brought more favorable results in terms of the physical properties and its ease of scale-up. Therefore, it is expected that a new BC production method, like air circulation culture using SFW, would contribute greatly to BC-related manufacturing.

• Korean Journal of Environmental Agriculture
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• v.31 no.4
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• pp.368-374
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• 2012

BACKGROUND: The urgency of feeding the world's growing population while combating soil pollution, salinization and desertification requires suitable biotechnology not only to improve crop productivity but also to improve soil health through interactions of soil nutrient and soil microorganism. Interest in the utilization of microbial fertilizer has increased. A principle of nature farming is to produce abundant and healthy crops without using chemical fertilizer and pesticides, and without interrupting the natural ecosystem. Beneficial microorganisms may provide supplemental nutrients in the soil, promote crop growth, and enhance plant resistance against pathogenic microorganisms. We mixed beneficial microorganisms such as Bacillus sp. Han-5 with anti-fungal activities, Trichoderma harziaum, Trichoderma longibrachiatum with organic material degrading activity, Actinomycetes bovis with antibiotic production and Pseudomonas sp. with nitrogen fixation. This study was carried out to investigate the mixtures on the soil microflora and soil chemical properties and the effect on the growth of lettuce and cucumber under greenhouse conditions. METHODS AND RESULTS: The microbial mixtures were used with each of organic fertilizer, swine manure and organic+swine manure and compared in regard to changes in soil chemical properties, soil microflora properties and crop growth. At 50 days after the treatment of microorganism mixtures, the pH improved from 5.8 to 6.3, and the EC, $NO_3$-Na and K decreased by 52.4%, 60.5% and 29.3%, respectively. The available $P_2O_5$ and $SiO_2$ increased by 25.9% and 21.2%, respectively. Otherwise, the population density of fluorescent Pseudomonas sp. was accelerated and the growth of vegetables increased. Moreover, the population density of E. coli and Fusarium sp., decreased remarkably. The ratio of bacteria to fungi (B/F) and the ratio of Actinomycetes bovis to fungi (A/F) increased 2.3 (from 272.2 to 624.4) and 1.7 times (from 38.3 to 64), respectively. Furthermore, the growth and yield of cucumber and lettuce significantly increased by the treatment of microorganism mixtures. CONCLUSION(S): These results suggest that the treatment of microorganism mixtures improved the chemical properties and the microflora of soil and the crop growth. Therefore, it is concluded that the microorganism mixtures could be good alternative soil amendments to restore soil nutrients and soil microflora.