• The Plant Pathology Journal
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• v.17 no.6
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• pp.367.2-367
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• 2001

• Research in Plant Disease
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• v.19 no.1
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• pp.7-11
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• 2013

Forty eight isolates of Botrytis elliptica and 23 isolates of B. cinerea from several locations in Korea were tested for resistance to fungicides used in the farmer's fields. Isolation frequency of B. elliptica having $EC_{50}$ (effective concentration of 50%) value $500-1000{\mu}g/ml$ to benomyl and mancozeb appeared highly, suggesting that the two fungicides are not effective in controlling leaf blight of lily in the field. The isolates were tested for resistance to fungicides procymidone and iprodione which were most commonly used in the farmer's fields. The rates of $EC_{50}$ value $5-50{\mu}g/ml$ to procymidome and iprodione were 93.7% and 100%, respectively, and those of $0-0.1{\mu}g/ml$ to diethofencarb+carbendazim and fludioxonil were 98.0% and 93.8%, respectively. In the rain-protected cultivation, control of leaf blight of lily was the most effective when iprodine, diethofencarb+carbendazim, and fludioxonil were sprayed alternately four times during the growing season.

• The Korean Journal of Mycology
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• v.27 no.4 s.91
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• pp.280-282
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• 1999

A new disease on mask melon grown under plastic film houses was found in Namhae area in May of 1999. Gray to dark brown mold were grown on the surface of matured fruits and infected inside tissues were discolored and rotten. Basal part of the fruit and blossom-end were frequently infected and colonized by fungi. About 2.2% of matured fruits were infected in the surveyed plastic film houses. The causal organism was isolated from the lesion and identified as Botrytis cinerea. The conidia in mass were hyaline or gray, 1-celled, mostly ellipsoid or ovoid and sized $8.8{\sim}21.2{\times}6.5{\sim}13.1\;{\mu}m$. Hyaline or pigmented conidiophores were tall, slender and determinated and, sometimes branched irregularly in upper part. Enlarged or rounded apical cells bear conidial cluster and sized $18.4{\sim}81.1{\times}4.3{\sim}11.4\;{\mu}m$. Optimum temperature for mycelial growth was recorded at $15{\sim}25^{\circ}C$. This is the first report on gray mold of melon caused by Botrytis cineria in Korea.

• Research in Plant Disease
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• v.9 no.3
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• pp.170-173
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• 2003

For the effective chemical control to minimize infection of storage pathogens on kiwifruit in the field, this study was conducted to screen alternative fungicides which could be substituted for the fungicides Benomyl WP and Thiophanate-methyl 제 registered for the control of postharvest fruit rats of kiwifruit in Korea. Among the 8 fungicides tested, Tebuconazole WP, Iprodione WP and Flusilazole WP showed higher inhibitory effects on themycelial growths of 3 major pathogens of postharvest fruit rots, Botryosphaeria dothidea, Diaporthe actinidiae and Botrytis cinerea on potato dextrose agar. They also showed control efficiencies as high as those of Benomyl WP and Thiophanate-methyl WP on postharvest fruit rots in the field. They might be good candidates for fungicieds for the control of postharvest fruit rots of kiwifruit.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.193-198
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• 2009

A full-length cDNA of OgGRP gene encoding a glycinerich cell wall protein was isolated from wild rice (Oryza grandiglumis). Deduced amino acid sequences of OgGRP are composed of 148 amino acids (16.3 kDa), and show 85.9% homology with Osgrp-2 (Oryza sativa). RT-PCR analysis showed that RNA expression of OgGRP was regulated by defense-related signaling chemicals, such as cantharidin, endothall, jasmonic acid, wounding, or yeast extract treatment. In relation to pathogen stress, the function of OgGRP was analyzed in OgGRP over-expressing Arabidopsis thaliana. Overexpression of OgGRP in Arabidopsis contributed to moderate resistance against fungal pathogen, Botrytis cinerea, by lowering disease rate and necrosis size. In the analysis of the transgenic Arabidopsis lines to check the change of gene expression profile, induction of PR1, PR5 and PDF1.2 was confirmed. The induction seemed to be caused by the interaction of ectopic expression of OgGRP with SA-and JA-dependent signaling pathways.

• Journal of Bio-Environment Control
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• v.21 no.2
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• pp.134-139
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• 2012

Inhibition effects on spore germination and mycelia growth for gray mold (Botrytis cinerea) were investigated in vitro using environment-friendly agricultural materials as well as environment-friendly pesticides. The inhibition effect on mycelia growth of gray mold is the highest when the gray mold mycelia were treated with a pesticide (commercial name: Koreayeok, Jihabudea KM, Sootingtan, Sootingstar) that contains a mixture of Bacillus subtilis, resulting in 100% inhibition of the mycelia growth. Meanwhile, the range of less than 20% inhibition effects on the growth of gray mold mycelia was observed with other commercial agricultural materials. The significant inhibition effects on spore germination of gray mold fungus were shown in vitro with two water dispersible pesticides containing sulfur [BTB (97.7%) and SulfurStar (92.3%)], respectively. These in vitro results of inhibiting of the spore germination and mycelia growth together cannot found. It remains to be determined whether the selected environment-friendly agricultural materials in effective control of gray mold in vitro can be used to control gray mold in field.

• The Plant Pathology Journal
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• v.17 no.3
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• pp.149-153
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• 2001

A total of 2109 isolates of Botrytis cinerea were collected from infected plants fo strawberry, tomato, and cucumber in Korea from 1994 to 1996. Based on in virtotests for mycelial growth on potato-dextrose agar containing fungicides, the esolates were classified into six phenotypic groups : SSR, SRR, RSS, RRS, RSR, and RRR, representing sensitivity (S) or resistance (R) to carbendazim, procymidone, and diethofencarb. In that order the isolation frequencies of the SSR, SRR, RSS, RRS, RSR, and RRR phenotypes were 28.7, 1.1, 28.8, 39.4, 1.0, and 0.9%, respectively. Three isolates from each SSR, SRR, RSS, RRS, and RSR and an isolate of RRR phenotype were selected and evaluated for their fitness-related characteristics such as pathogenic aggressiveness, mycelial growth rate, sporulation, and sclerotial formation. Competitive abilities of the SSR, SRR, RSS, RRS, and RSR phenotypes were also compared by inculating mixtures of conidial suspensions of two phenotypes to cucumber plant, and then determining re-isolation frequencies from lesions. In general, significant differences in fitness-related characteristics, except pathogenic aggressiveness, were found not only between but also within phenotype groups. In the competitiveness tests, carbendazim-sinsitive phenotypes (SSR and SRR) were found to be more competitive than the resistant ones (RSS and RSR), whereas, the procymidone-resistant phenotypes (SRR and RRS) appeared to be more competitive than the sensitive ones (SSR, RSS, and RSR). There was no consistent dominance in competitiveness between the diethofencarb-resistant and sensitive phenotypes. The RSR phenotype was the least competitive among the five phenotypes.

• The Plant Pathology Journal
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• v.36 no.6
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• pp.579-590
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• 2020

Botrytis cinerea, which causes gray mold disease in more than 200 plant species, is an economically important pathogen that is mainly controlled by synthetic fungicides. Synergistic fungicide mixtures can help reduce fungicide residues in the environment and mitigate the development of fungicide-resistant strains. In this study, we screened microbial culture extracts on Botrytis cinerea to identify an antifungal synergist for tebuconazole. Among the 4,006 microbial extracts screened in this study, the culture extract from Schizophyllum commune displayed the most enhanced activity with a sub-lethal dosage of tebuconazole, and the active ingredient was identified as schizostatin. In combination with 5 ㎍/ml tebuconazole, schizostatin (1 ㎍/ml) showed disease control efficacy against gray mold on tomato leaf similar to that achieved with 20 ㎍/ml tebuconazole treatment alone. Interestingly, schizostatin showed demethylation inhibitor (DMI)-specific synergistic interactions in the crossed-paper strip assay using commercial fungicides. In a checkerboard assay with schizostatin and DMIs, the fractional inhibitory concentration values were 0.0938-0.375. To assess the molecular mechanisms underlying this synergism, the transcription levels of the ergosterol biosynthetic genes were observed in response to DMIs, schizostatin, and their mixtures. Treatment with DMIs increased the erg11 (the target gene of DMI fungicides) expression level 15.4-56.6-fold. However, treatment with a mixture of schizostatin and DMIs evidently reverted erg11 transcription levels to the pre-DMI treatment levels. These results show the potential of schizostatin as a natural antifungal synergist that can reduce the dose of DMIs applied in the field without compromising the disease control efficacy of the fungicides.

• The Plant Pathology Journal
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• v.35 no.1
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• pp.71-76
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• 2019

$SdhB^{P225F}$ and $SdhB^{H272R}$ mutations have been found associated with boscalid resistance in Botrytis cinerea from strawberry in Shanghai, China. For rapid detection of two mutations, tetra-primers were designed and optimized to gain the relatively high accuracy and specificity based on the ARMS-PCR technique, by which resistance can be identified with different lengths of products on agarose gels. The tetra-primer ARMS-PCR systems for $SdhB^{P225F}$ and $SdhB^{H272R}$ were validated by 9 SdhB-squenced strains repeatedly. Then, sensitivity of 30 more strains were also tested by the methods, which were accordant with genotypes by sequencing and the sensitivity of conidial germination to boscalid by 100%. Thus, the methods developed in this study are proved to be rapid, inexpensive, accurate and practical for resistance detection of Botrytis cinerea caused by $SdhB^{P225F}$ and $SdhB^{H272R}$ mutations.

• Journal of Life Science
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• v.14 no.1
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• pp.193-197
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• 2004

A continuous enrichment culture procedure was used to isolate bacteria from various soil sources capable of suppressing large patch disease of turfgrass. Six isolates consistently suppressed large patch in turfgrass, and ranged in the spectrum of extracellular enzymes that they expressed. The best disease- suppressing isolate, TBM912, expressed protease, CMCase, and pectinase activity and inhibited the growth of Rhizectonin solani and Betrytis cinerea in vitro. Here we show that this strain also produces an antibiotic that was identified by TLC, SDS-PACE and HPLC analysis as lipopeptide.