• The Plant Pathology Journal
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• v.25 no.2
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• pp.165-171
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• 2009

Biological control activity of Acremonium strictum BCP, a mycoparasite on Botrytis cinerea, was examined against six plant diseases such as rice blast, rice sheath blight, cucumber gray mold, tomato late blight, wheat leaf rust, and barley powdery mildew in growth chambers. The spore suspension of strain BCP showed strong control activities against five plant diseases except against wheat leaf rust. On the other hand, the culture filtrate of A. strictum BCP was effective in controlling only cucumber gray mold and barley powdery mildew. Further in vivo biocontrol activities of A. strictum BCP against tomato gray mold were investigated under greenhouse conditions. Control efficacy of the fungus on tomato gray mold increased in a concentration-dependent manner. Treatment of more than $1{\times}10^6$ spores/ml significantly controlled the disease both in tomato seedlings and in adult plants. The high disease control activity was obtained from protective application of the strain BCP, whereas the curative application did not control the disease. Foliar infections of B. cinerea were controlled with $1{\times}10^8$ spores/ml of A. strictum BCP applied up to 7 days before inoculation. In a commercial greenhouse, application of A. strictum BCP exhibited the similar control efficacy with fungicide procymidone (recommended rate, $500{\mu}g/ml$) against strawberry gray mold. These results indicate that A. strictum BCP could be developed as a biofungicide for Botrytis diseases under greenhouse conditions.

• The Korean Journal of Pesticide Science
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• v.7 no.2
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• pp.83-91
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• 2003

Methanol extracts from 207 samples of 118 plant species in 44 families were tested for their fungicidal activities against six phytopathogenic fungi. Extracts of Thuja orientalis leaf, Cinnamomum loureirii leaf, Lindera erythrocarpa barks and leaf, Pinus koraiensis wood, Hovenia dulcis wood, Koelreuteria paniculata barks, Styrax japonica wood, Camelia japonica leaf and Cleyera japonica leaf showed very strong fungicidal activity against more than two phytopathogenic fungi at a concentration of 2000 ppm. As a naturally occurring fungicide, these plants could be useful as new fungicidal products against various plant diseases induced by plant pathogens.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.261-265
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• 2010

Lichens, a symbiotic organism of fungi and algae, cause serious damage to national heritages of stone master piece and costly trees for gardening. The present study was conducted to screen effective fungicides against lichen-forming fungi to control the biological agents deteriorating stone heritages and trees. Five commercial fungicides (Fenarimol EC, Etridiazole EC, Iminoctadinetriacetate SL, Difenoconazole+lminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC) were tested against the lichen-forming fungi (LFF) isolated from seven saxicolous (Caloplaca sp., Ramalina sp., Xanthoparmelia sp., and Xanthoria sp.,) or corticolous (Parmelia sp.,) lichen species. Preliminary screening test showed that no LFF could grow on the MY (malt-yeast extract) agar medium amended with the recommended concentrations of each fungicide. Further screening was conducted at 1%, 10% and 20% of the recommended concentrations of the fungicides. After 7 week incubation at $15^{\circ}C$ in the dark, Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC completely inhibited the fungal growth of all the tested LFF, even at 1% of the concentration. Two fungicides of Fenarimol EC and Iminoctadinetriacetate SL exhibited a moderate inhibition activity at the lower concentrations. Etridiazole EC was less effective in the fungal growth inhibition than the other four fungicides. The results suggested that lichens colonizing on precious stone heritages and trees can be eradicated by applying Difenoconazole+Iminocatadinetriacetate ME and Difenoconazole+Azoxystrobin SC even 1% of the recommended concentrations. Selected fungicide application at such a low concentration will facilitate the chemical use to prevent and preserve stone heritages from biological deterioration induced by lichens and the allied microbes.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.32-41
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• 2000

Antimicrobial and antioxidative activities on heartwood extractives from Zelkova serrata were investigated to develop a natural fungicide or preservative. The ethanol extract from Z. serrata was fractionated in the order of petroleum ether, diethylether and ethylacetate to determine antimicrobial activity. The highest antimicrobial activity against the tested microorganisms was found in the petroleum ether soluble fraction. An active antimicrobial compound was isolated from petroleum ether soluble fraction, and identified as 7-hydroxy-3-methoxycadalene by $^1H$-, $^{13}C$-NMR and EI-MS spectrometry. This compound showed higher antifungal activity, but lower antibacterial activity than hinokitiol(${\beta}$-thujaplicin), strong antimicrobial compound isolated from Thujopsis dolabrata. Antioxidative activity was also higher than ${\alpha}$-tocopherol and similar to BHT(butylated hydroxytoluene), one of the strongest synthetic antioxidant. As a result, it was concluded that 7-hydroxy-3-methoxycadalene isolated from Z. serrata had strong antifungal and antioxidative activities.

• The Korean Journal of Pesticide Science
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• v.11 no.4
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• pp.305-312
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• 2007

It was the investigated the response to metalaxyl of Phytophthora capsici isolates collected in 2005 and 2006. With effective concentrations ($EC_{50}$) of metalaxyl causing 50% growth inhibition, resistance baseline was determined as more than $1.0\;{\mu}g\;mL^{-1}$. Based on the resistance baseline, isolation frequency (%) of P. capsici resistant to metalaxyl was 29.0% and 218% in 2005 and 2006, respectively. Among the isolates of P. capsici obtained in 2006, the isolation was variable; 33.3% in Chungnam, 26.3% in Chungbuk and 11.1% in Gyeongbuk. Two isolates of metalaxyl-sensitive (MS) and too isolates of metalaxyl-resistant (MR) P. capsici were selected and then used to investigate the activity of metalaxyl to their development stages. Even though there was a difference in mycelial growth inhibition by metalaxyl between MS and MR isolates, the fungicide was not active or nearly to sporangium germination, zoospore release, and zoospore germination of both MS and MR isolates. However, the fungicide showed weak activity against sporangium germination and zoospore release of P. capsici, not related with its resistance. Also, it was not inhibitory to zoospore germination of both resistant and sensitive isolates. In a greenhouse test, it showed 100% of control value against P. capsici 06-86 sensitive to metalaxyl, when it was applied by soil-drenching at $25\;{\mu}g\;mL^{-1}$. However, 06-130 and 16-155 resistant to metalaxyl showed less than 20% of control value.

• Research in Plant Disease
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• v.16 no.1
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• pp.27-34
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• 2010

This study was performed to develop a formulation using an antagonistic bacterium Bacillus amyloliquefaciens A-2 to control tomato leaf mold caused by Fulvia fulva. B. amyloliquefaciens A-2 was grown in a medium with rice oil and mixed with various carrier and additives. One of the formulations, A2-MP, showed the best disease control value among the tested formulations. The disease control value of A2-MP at 100-fold and 500-fold diluted treatment was not significantly different from that of chemical fungicide triflumizole in a growth chamber. Although disease control effect was decreased by serial diluted treatment of the prepared A2-MP, 1,000-fold diluted treatment of A2-MP still showed high disease control value of 72.0%. For the green house experiments, the disease control values of A2-MP was indicated as 79.4% which is similar to that of chemical fungicide, triflumizole showing 79.6%. When the disease control activity of the formulation A2-MP was compared in tomato production conditions, disease control values of 100-fold diluted A2-MP and 3,000 fold diluted triflumizole exhibited 60%, 81.6%, respectively. The disease control efficiency by A-2MP was 73% of the disease control value of chemical fungicide. The formulation A-2MP maintained the stable bacterial viability and disease control activity when stored at $4^{\circ}C$. This result suggested that A-2MP develped from B. amyloliquefaciens A-2 could be used to control tomato leaf mold.

• The Korean Journal of Pesticide Science
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• v.5 no.3
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• pp.18-25
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• 2001

Ethanol extracts from 46 plants were tested for their fungicidal activity against six plant diseases consisting of Maynaporthe grisea, Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia recondita, and Erysiphe graminis in the greenhouse studies. Strong activity at 5 and 10 mg/pot was produced from the extracts of Helianthus annuus flowers and Zea mays leaves against P. grisea. In a test with B. cineara, extracts of H. annuus leaves, H. annuus flowers, Chrysanthmum coronarium var. spatiosum, Cucurbita moschata seeds, Lycopersicon esculentum, Z. mays, and Z. mays leaves had strong activities at 5 mg/pot. In a test with P. recondita, strong activity was obtained from the extracts of Capsicum frutescens, C. moschata seeds, H. annuus seeds, L. esculentum, and Malva veticillata at 5 mg/pot. Against E. graminis, extracts of Cucumis sativus, H. annuus seeds, Salanum tuberosum, Z. mays, and Z. mays leaves produced strong activities at 10 mg/pot. All the extracts were ineffective against P. infestans and R. solani. Among seven extracts tested, the extracts of H. annuus leaves and flowers were highly effective against all the strains of B. cinerea resistant to carbendazim, procymidone, and diethofencarb. Furthermore, potent fungicidal activity was produced from the extracts of C. coronarium var. spatiosum and C. moschata seeds against the SSR, SRR, and RSR strains of B. cinerea, and Z. mays and Z. mays leaves against SSR and RSR. Extract of L. esculentum showed very strong activity only against RRS of B. cinerea.

• Applied Biological Chemistry
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• v.33 no.3
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• pp.231-238
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• 1990

The structure-antifungal activity correlations between the structure of fourteen new 1-(phenoxymethyl)benzotriazoles (I) (Y=0), 1-(thiophenoxymethyl)benzotriazoles (ll) (Y=S) and 1-(azidomethyl)benzotriazole (III) derivatives were synthesized, and their activity, fifty percent inhibition of mycelial growth($pI_{50}$), in vitro against Pyricularia oryzae, Fusarium axysporum f.sp sesami, Valsa ceratosperma and Botrytis cinerea were investigated using a generalized QSAR method. The activity of (I) was superior In those of (II) and (III). The effect of the substituents (X) on the phenoxy group (I) was rationalized by a parabolic function of electronic (${\sigma}$), steric ($B_1$) and hydrophobic parameter(${\pi}$), and hydrogen bonding (HB). Where the optimal values of substituent on the fungicidal activity againt P. oryzae and F. axysporum f.sp.sesami are $B_1=1.40A;(H)$ and ${\pi}=0.07{\sim}0.15;(H)$, and those of substituent on the fungicidal activity against V. ceratosperma and B. cinerea are ${\sigma}=0.23{\sim}0.28;\;(C1),\;{\pi}=0.70;$ (C1), respectively. The most effective compound ( I a) and ( I d) were examined in this study.

• Journal of the Korean Wood Science and Technology
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• v.29 no.2
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• pp.140-145
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• 2001

Antimicrobial and antioxidative activities on heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. Six flavanones including pinostrobin, eriodictyol, naringenin, pinocembrin, taxifolin and verecundin were isolated from Prunus sargentii which has been selected due to its high antimicrobial and antioxidative activities among the tested species. According to the results of antifungal test, pinocembrin was evaluated as the highest antifungal compound among the test compounds, which showed 80% of hyphal growth inhibition rate. Antifungal activity of pinocembrin was similar to hinokitiol(${\beta}$-thujaplicin), strong antimicrobial compound isolated from Thujopsis dolabrata. Naringenin followed pinocembrin in its antifungal activity. However, verecundin did not show any antifungal activity. No compound was effective in antibacterial activities. As a result of the measurement of free radical scavenging activity, antioxidative activities of taxifolin and eriodictyol were 2 times that of ${\alpha}$-tocopherol, and antioxidative index of these compounds were even superior to that of ${\alpha}$-tocopherol. In this regard, it could inferred that high antifungal and antioxidative activities of extractives of P. sargentii were derived from pinocembrin, taxifolin and eriodictyol, respectively.

• Journal of the Korean Wood Science and Technology
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• v.30 no.4
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• pp.51-57
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• 2002

Antimicrobial and antioxidative activites on heartwood extractives of domestic species were investigated to develop a natural fungicide or preservative. One steroid, stilbene derivatives and two flavonoids were isolated from heartwood of Robinia pseudo-acacia which has been selected due to its high antioxidative activity among the tested species. The structures were determinded as: 3-𝛽-stigmast-5-en-3-ol(daucosterol), 3,3'4,5-tetrahydroxystilbene, 3,3'4'5,7-pentahydroxyflavone(robinetin) and 3,3'4'7-tetrahydroxyflavanone(fustin) respectively on the basis of spectroscopic data and chemical correlations. According to the results of free radical scavenging activity, 3,3'4'5,7-pentahydroxyflavone was evaluated as the highest antioxidative compound among the four compounds and showed higher radical scavenging activity than those of 𝛼-tocopherol and butylated hydroxytoluene(BHT), one of the strongest synthetic antioxidants. 3,3'4'5-Tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone showed higher antioxidative activities than that of 𝛼-tocopherol. However, 3-𝛽-stigmast-5-en-3-ol did not show free radical scavenging activity. In this regard, it could inferred that high antioxidative activity of extractives of R. pseudo-acacia was derived from 3,3'4'5'7-pentahydroxyflavone, 3,3'4'5-tetrahydroxystilbene and 3,3'4'7-tetrahydroxyflavanone.