• Asian Journal of Turfgrass Science
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• v.21 no.2
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• pp.147-154
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• 2007

In March of 2004, gray snow mold (Typhula blight) caused by Typhula spp. occurred on perennial ryegrass (Lolium perenne L.) and Kentucky bluegrass (Poo pratensis L.) at MuJu golf courses in Jeonbuk Province. Leaves in the affected areas were matted together and frequently covered with white to grayish mycelia. Sclerotia were formed on the leaf blade, leaf sheath, or crown regions. The fungus isolated from the diseased leaf formed whitish mycelium, clamp connections, and light pink to brown, irregular-shaped small sclerotia of less than 1.4 mm in diameter, which are characteristic to Typhula incarnata. Optimum temperature ranges for mycelial growth were $5^{\circ}C$ to $15^{\circ}C$. The causal organism was confirmed to be T. incarnata as the partial sequence of its ribosomal RNA ITS1 (internal transcribed spacer) region was 91% homologous to those of T. incarnata in GenBank database. Out of the 14 fungicides tested fur antifungal activity in vitro, 10 fungicides including iprodione, tebuconazole, polyoxin D, flutolanil, hexaconazole, tolclofos-methyl, fosetyl-Al, mepronil, pencycuron+tebuconazole, and fenarimol completely inhibited fungal growth at their recommended concentrations. In the field test, these fungicides and others such as thifluzamide and thiram effectively controlled the gray snow mold of turfgrass with some variable degrees of control efficacies.

• Korean journal of applied entomology
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• v.11 no.1
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• pp.19-23
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• 1972

Apple cankers caused by Valsa mali Miyabe, Botryosphaeria ribis Cross, Phomopsis truncicola Miura, are distributed in the main apple growing areas, Choong Chung Puk Do, Choong Chung Nam Do, and Kyung Sang Puk Do. According to the survey in 1970 that Valid mali is the dominant causal organism among the three in the most severely damaged area. Valsa mali and Botryosphaeria ribis were found in ail 3 provinces, however, Phomopsis truncicola was not found in Choong Chung Nam Do. Especially, Botryosphaeria ribis was most abundant in Chunwon of Choong Chung Nam Do. Effects of chemical control of apple canker caused by Valsa mali were tested both on potato dextrose agar with inhibition zones produced by the fungicides and relative growth of assay fungus of peridermis was treated with tile fungicides. Ifost effective was mercuric and followed by Lime sulfur, Hydroquinone sulfate, in general.

• Weed & Turfgrass Science
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• v.2 no.4
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• pp.408-412
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• 2013

Dollar spot caused by Sclerotinia homoeocarpa F.T. Benn. is a common and economically important turfgrass disease in South Korea. Fungicides mixture (propiconazole 25% + boscalid 47%) treatments, showing synergistic interaction, with three application rates (low: 50.3 ml $10a^{-1}$ and 97.5 g $10a^{-1}$, intermediate: 67.0 ml $10a^{-1}$ and 130.0 g $10a^{-1}$, and high: 100.5 ml $10a^{-1}$ and 195.0 g $10a^{-1}$) and two application intervals (10 and 15 days) were evaluated for control of dollar spot in creeping bentgrass golf course putting green. In both nontreated plots of field A and B, the disease has severed as 48.3 and 60.0% after the pathogen inoculation. Two fungicide mixture treatments showed significantly higher the disease control effect than a single fungicide treatment (propiconazole). Field A which showed more the disease severity but the fungicide still showed acceptable level of the disease efficacy (89.0%), significant differences in control value were not detected among treatments. The results suggest that the lower application rate of two fungicides mixture treatments may reduce the dollar spot disease severity in creeping bentgrass golf course putting green.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.379-386
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• 2013

Aphidius colemani and Orius laevigatus aree natural enemies of the control cotton aphid and western flower thrips, which are the major pests of cucumber plants. We evaluated the low toxicity of 47 fungicides against A. colemani and O. laevigatus, and we investigated the simultaneous effect of the natural enemies with fungicide of low toxicity on the pests. The toxicity of DBEDC, hexaconazole, pyraclostrobin, tribasic copper sulfate, triflumizole, chlorothalonil, flusilazole, folpet, carbendazim+diethofencarb, cymoxanil+fenamidone and trifloxystrobin to A. colemani mummies was more than 50% and to O. laevigatus was low toxic. Among the fungicides with low toxicity, azoxystrobin 20% WP was selected because it could be used simultaneously with A. colemani and O. laevigatus and as a fungicide to control powdery mildew and downy mildew. In 2011, the densities of western flower thrips and cotton aphid increased rapidly in early-May in Gongju and Cheonan, Chungnam Province. When azoxystrobin was used at an interval of 10 days in spring, A. colemani and O. laevigatus were released at an interval of 7 days at the early occurrence of the pests. The natural enemies decreased the densities of the pests; the maximum number of A. colemani mummies was 18 per lower leaf, and the maximum number of O. laevigatus was 0.5 per flower. Azoxystrobin did not influence the densities of A. colemani and O. laevigatus. The results show that the selected fungicides can be used with A. colemani and O. laevigatus for the intergrated pest management of cotton aphid and western flower thrips in cucumber polyvinyl house cultivation.

• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.73-83
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• 2005

This study was carried out to investigate control efficacy of fungicides mixed with pyroligneous acid on Large patch caused by Rhizoctonia solani AG2-2. R. solani AG2-2 was not inhibited by concentration of 500 times and 1,000 times diluents of pyroligneous acid. It is thought that R. solani AG2-2 was not inhibited by Pyroligneous acid alone. Pencycuron and tebuconazol mixed with pyroligneous acid had a good effect in prevention of R. solani AG2-2 in zoysiagrass. Concurrently, it was observed that those were reduced $50\%$ of usage of fungicides. 500 times and 1,000 times diluents of pyroligneous acid treated group had a significantly effect compared to control turf in the leaf length, leaf width and dry weight. In conclusion, usage of fungicides could be reduced about $50\%$ by a fungicides mixed with pyroligneous acid for protection of R. solani AG2-2. Therefore, It is thought that fungicides mixed with pyroligneous acids can be reduced an economic load and also an environmental pollution such as a tolerance to pathogenic bacteria and a destruction of an ecological system of soil microbes according to use fungicides.

• Research in Plant Disease
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• v.19 no.1
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• pp.1-6
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• 2013

Optimal spray time, interval and number of preventive fungicides against fruit rots of kiwifruit were investigated at the orchard which both green kiwifruit cultivar 'Hayward' and gold kiwifruit cultivar 'Hort16A' are cultivating side by side during 2009 and 2010 growing seasons in Jeju island, Korea. The highest control efficiency was obtained from benomyl WP and followed by thiophanate-methyl WP and carbendazim+diethofencarb WP. The control efficacies of the fungicides were much higher when applied onto the kiwifruit canopy after the flowering time than before the flowering time but thereafter their control efficiencies were decreased drastically according to delays of spray timing. With increasing spray numbers of the fungicides, the control efficacy increased. However, optimal spray time, interval and number of the preventive fungicides for the effective control of fruit rots of kiwifruit were determined as 4 time-spray schedule with 2-week-interval just after the flowering time on both 'Hayward' and 'Hort16A' cultivars.

• The Korean Journal of Mycology
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• v.17 no.4
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• pp.184-188
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• 1989

Effect of Metalaxyl-Mz and Aliette-F to Phytophthora capsici was studied in vitro and in vivo. Metalaxyl-Mz was more inhibitory than Aliette-F on Mycelial growth. Although Aliette-F had more inhibitory effect on zoosporangial formation, there was no big difference among the other concentrations of the two fungicides. A higher inhibitory trend of zoosporangial formation, however, was resulted by the chemical when compared to the control. The extract obtained from the red pepper treated with Metalaxyl-Mz showed a good inhibitory effect on mycelial growth, and there was not so big difference between 400 and 600 times concentrations. The 1000 times concentration was less inhibitory than the above two concentration levels. Although there no distinct difference the two chemicals, Aliette-F and Metalaxyl-Mz, however, preventive effect was higher than curative effect under the green house tests.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.88-88
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• 2003

건고추는 대부분 세척이나 살균의 과정을 거치지 않고 저장, 유통되므로 해충이나 미생물 오염에 의한 식품위생면이나 상품가치면에서 문제가 되고 있다. 고춧가루의 미생물과 해충 방제를 위하여 ethylene oxide나 propylene oxide 등의 훈증제가 사용되고 있으나 문제점이 많아 점차 사용이 금지되고 있는 실정에 있다. ${\gamma}$-선 조사는 훈증제, 자외선 조사, 초단파 처리등 기존의 방법에 비해 살균 효과는 물론 식품의 품질과 건전성 실험 결과에서도 우수하다고 보고되었다. (중략)

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.53-55
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• 1969

1. This experiment was made for a comparable test of five different chemicals on control effects of mulberry die back disease from the autum of 1967 to that of 1968. These chemicals were EMP, PMF, lime sulfur, chlon, and PMA. 2. The experiment showed the EMP and PMF were the best chemicals among those for controling it, and the others no significance comparing with the control. 3. The best way was a twice sprang of 150$\ell$ EMP(1/1500 con.) per 10ar to the base of branches to the full extent through september and october.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.151-155
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• 2011

The fungus Botrytis cinerea causes fruit rot of strawberry and the damages can result in harvest losses upto 50%. Proper timing of fungicide application is essential for successful control of Botrytis fruit rot, fenhexamid plus iminoctadine tris, cyprodinil plus fludioxonil, fludioxonil alone, and Bacillus subtilis QST713 were applied to individual buds, flowers, and green and red fruit of cultivar 'Seolhyang' ex vivo. Cyprodinil plus fludioxonil or fludioxonil alone was applied i) before and after a 5-hr period of low-temperature ($0^{\circ}C$) incubation ex vivo ii) in field trials. Strawberry flowers and red fruit were more susceptible to B. cinerea than the green fruits. Incidence of Botrytis rot with fenhexamid plus iminoctadine tris and cyprodinil plus fludioxonil was the lowest at flowering, whereas B. subtilis QST713 did not significantly among treatments. In 2010, incidence of Botrytis fruit rot was significantly reduced when fludioxonil was applied two times at 1 week intervals from 50% bloom in field trials. Cultivars Redpearl and Seolhyang were more susceptible to low-temperature than cvs. Maehyang and Akihime. Cyprodinil plus fludioxonil application was effective when applied before onset of the low-temperature treatment period. Fludioxonil showed the most effective when it was sprayed one and more than two times in before and post low-temperature condition, respectively. These results demonstrate that fungicide selection and timing can interact with stage of fruit development and low-temperature in determining effectiveness of suppression of Botrytis fruit rot.