• The Plant Pathology Journal
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• v.28 no.1
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• pp.68-74
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• 2012

Biocontrol microbes have mainly been screened among large collections of microorganisms $via.$ nutrient-rich $in$ $vitro$ assays to identify novel and effective isolates. However, thus far, isolates from only a few genera, mainly spore-forming bacilli, have been commercially developed. In order to isolate field-effective biocontrol microbes, we screened for more than 200 oligotrophic bacterial strains, isolated from rhizospheres of various soil samples in Korea, which induced systemic resistance against the soft-rot disease caused by $Pectobacterium$ $carotovorum$ SCC1; we subsequently conducted in $planta$ bioassay screening. Two oligotrophic bacterial strains were selected for induced systemic disease resistance against the $Tobacco$ $Mosaic$ $Virus$ and the gray mold disease caused by $Botrytis$ $cinerea$. The oligotrophic bacterial strains were identified as $Pseudomonas$ $manteilii$ B001 and $Bacillus$ $cereus$ C003 by biochemical analysis and the phylogenetic analysis of the 16S rRNA sequence. These bacterial strains did not exhibit any antifungal activities against plant pathogenic fungi but evidenced several other beneficial biocontrol traits, including phosphate solubilization and gelatin utilization. Collectively, our results indicate that the isolated oligotrophic bacterial strains possessing induced systemic disease resistance could provide useful tools as effective biopesticides and might be successfully used as cost-effective and preventive biocontrol agents in the field.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.199-204
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• 2013

The nematicidal, antifungal and antioxidant activities of methanol extracts from six Vietnamese native medicinal plants were evaluated by various assays in vitro. Of the plant extracts tested, Terminalia nigrovenulosa was found to possess the highest activity when compared to the others. The leaves and bark of T. nigrovenulosa showed strong inhibitory activity against Meloidogyne incognita and Fusarium solani. The DPPH (1,1-Diphenyl-2-picryl-hydrazyl) radical scavenging, reducing power and total antioxidant activities of T. nigrovenulosa bark were higher than that of the remainder plant extracts. Chitinase activity of these plants was also investigated using SDS-PAGE. The results obtained in the present study indicate that T. nigrovenulosa leaf extracts are the greatest potential source as nematicides and fungicides for the control of M. incognita and F. solani. In particularly, T. nigrovenulosa bark extracts could be used as a potential source of commercially viable levels of natural antioxidant.

• Mycobiology
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• v.49 no.3
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• pp.294-296
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• 2021

An endolichenic fungus, Xylaria grammica strain EL000614, showed strong nematicidal effects against plant pathogenic nematode, Meloidogyne incognita by producing grammicin. We report genome assembly of X. grammica EL000614 comprised of 25 scaffolds with a total length of 54.73 Mb, N50 of 4.60 Mb, and 99.8% of BUSCO completeness. GC contents of this genome were 44.02%. Gene families associated with biosynthesis of secondary metabolites or regulatory proteins were identified out of 13,730 gene models predicted.

• Korean Journal of Organic Agriculture
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• v.23 no.2
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• pp.207-231
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• 2015

This study evaluate examines the efficiency and the improvement measurement of Oilseed crops (Sesame and Perilla). For this purpose, In the first stage, this study analyzes the current conditions of oilseed industry. In the second stage, this study evaluates the efficiency and super-efficiency of environmentally-friendly agricultural product producers. The result of this study show that: (1) Changes in annual wholesale price of Sesame and Perilla; (2) An efficiency and ranking of environmentally-friendly product producers; (3) The solutions and improvement measurements for inefficient producers.

• Korean Journal of Organic Agriculture
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• v.16 no.4
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• pp.391-408
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• 2008

The overall focus of this study was to identify marketing and promotion strategies that can maintain and enhance environmentally friendly farm and organic production and processing activities. This is particularly important as the volume of environmentally friendly farm and organic produce that is generally available is increasing, and significant players, such as Organic Marketing Initiatives(OMI) and conventional marketing co-operatives, are becoming involved in the market. The rapid increase in production of environmentally friendly farm products and organic food is creating new and more complex challenges for marketing, from vegetable box schemes large co-operatives supplying the precise quality and volume required by supermarkets. A possible strategy for many farmers is to co-operate in regionally or nationally operating marketing initiatives. The main objective of any public relations(PR) activity should to enhance publicity and to improve an OMIs image. No promotion, no perception of OMI performance.

• Korean Journal of Organic Agriculture
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• v.16 no.3
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• pp.275-286
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• 2008

This paper examines the impact of reliability on consumers' demand for environmentally friendly agricultural products using ordered logit model. We survey 100 housewives living in the capital region and five metropolitian cities cross sectional data in 2007. This paper especially estimates the impact of instrumental factor, such as history tracking system, provision of information, safety assurance and labelling of brands on the consumers' demand. The main results show that provision of information and safety assurance affect consumers' demand more confident than others. In order to motivate consumers to buy more environmentally friendly agricultural products, the safety should be assured and more information on production and marketing channel should be labelled.

• Research in Plant Disease
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• v.20 no.3
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• pp.216-218
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• 2014

Lysobacter antibiocus HS124 is a chitinase-producing rhizobacterium with proven capacities to suppress plant diseases. Bacterial cultures of L. antibioticus HS124 showed strong biocontrol efficacies against various plant diseases compared to those of bacterial cultures of Bacillus subtilis QST713 which is an active ingredient of a commercial biopesticide, Serenade. Here, we report the draft genome sequence and automated annotation of strain HS124. This draft genome sequence indicates the novelty of L. antibiocus HS124 and a subset of gene functions that may be related to its biocontrol activities.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.5
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• pp.485-491
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• 2015

This study was performed to investigate thermophilic bacteria from soil having broad antifungal spectrum against Rhizoctonia solani, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f.sp. lycopersici, and Botrytis cinerea. One isolate selected could resist heat shock of $60^{\circ}C$ for one hour, and had broad antifungal activity in dual culture assay against all tested fungal pathogens and was identified as Bacillus amyloliquefaciens Y1 using 16S rRNA gene sequence. Further investigation for antifungal activity of bacterial culture filtrate (BCF) and butanol crude extract (BCE) of various concentrations showed broad spectrum antifungal activity and fungal growth inhibition significantly increased with increasing concentration with highest growth inhibition of 100% against R. solani with 50% BCF and 11 mm of zone of inhibition against R. solani with 4 mg BCE concentration. Treatment of butanol crude extract resulted in deformation, lysis or degradation of C. gloeosporioides and P. capsici hyphae. Furthermore, B. amyloliquefaciens Y1 produced volatile compounds inhibiting growth of R. solani (70%), C. gloeosporioides (65%) and P. capsici (65-70%) when tested in volatile assay. The results from the study suggest that B. amyloliquefaciens Y1 could be a biocontrol candidate to control fungal diseases in crops.

• Korean journal of applied entomology
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• v.60 no.4
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• pp.417-422
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• 2021

This study aimed to provide information on the biodiversity of various arthropods living in paddy fields during the winter season by examining their incidence density. Insect collection was carried out by 50 × 50 cm grids of soil surface and plants from paddy fields, as well as from ridges between paddies, using a battery-powered aspirator. The total number of individuals collected from paddy fields and inter-paddy ridges was 41,197, most of belonged to the orders Collembola, Hemiptera, and Diptera. Arthropods showed similar appearance patterns in fields under both organic and conventional farming. However, a higher number of insects was collected in organic farms. The species diversity, species richness, and species evenness were all greater in inter-paddy ridges than in paddy fields, in a statistically significant manner (P < 0.05).

• Korean Journal of Environmental Agriculture
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• v.36 no.1
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• pp.36-42
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• 2017

BACKGROUND: Yuza seed by-product has been produced in a large amount from the agricultural farms in the southern area of Korea. It has been mostly abandoned after commercial process for the production of juice, jam and tea. The study on the reuse of the yuza seed by-product has received much attention as a bio-resource material for the production of active compound in agriculture. METHODS AND RESULTS: Insecticidal rhamnolipid-producing Pseudomonas sp. EP-3 was grown in mineral salt media with the yuza seed by-product at 2, 20, 50 and 100 g/L. The growth of EP-3 was accompanied by a increase in insecticidal activity against green peach aphid. The highest insecticidal activity was observed when EP-3 was grown in the medium containing 50 g/L of the seed sample, producing approximately 996 mg/L of rhamnolipid at 96 h. Palmitic acid, stearic acid, oleic acid and linoleic acid were determined as the major fatty acids of the seed sample. The EP-3 cultures grown on the fatty acid mixture extracted from the seed sample showed a aphid mortality similar to that of cultures grown on the seed sample. The EP-3 cultures grown on 50 g/L of the seed sample showed aphid mortality more than 90% under greenhouse conditions. CONCLUSION: This study suggested that the yuza seed by-product may be used as a renewable material for microbial production of rhamnolipid against green peach aphid.