• The Plant Pathology Journal
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• v.22 no.3
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• pp.303-308
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• 2006

Ethaboxam is a fungicide controlling plant diseases caused by Oomycetes. Efforts were made to improve its fungicidal activity applying formulation technology. Fungicidal activity of ethaboxam against cucumber downy mildew caused by Pseudoperonospora cubensis was improved by incorporating polyoxyethylene cetyl ether (PCE) in a wettable powder formulation. It was found that the optimum combination ratio of PCE and ethaboxam was 3:1, and a tank-mix of $150{\mu}g/ml$ of ethaboxam and $450{\mu}g/ml$ of PCE would be as good as the standard 25 % WP formulation diluted to $250{\mu}g/ml$ ethaboxam without PCE in controlling cucumber downy mildew. Based on this results, a wettable powder (WP) co-formulation containing 15% of ethaboxam and 45% of PCE was developed in this study, and tested for its performance in the fields. This co-formulation showed significant improvement in persistence of fungicidal activity and curative efficacy of ethaboxam against cucumber downy mildew. The improved control efficacy was also confirmed for control of grape downy mildew caused by Plasmopara viticola and potato late blight caused by Phytophthora infestans in the field tests.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.59-63
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• 2005

Bacillus subtilis S1-0210 was selected as a biological agent against Botrytis cinerea in strawberry. The isolate inhibited mycelial growth of B. cinerea in vitro tests. A wettable powder formulation of B. subtilis S1-0210 significantly reduced infection rates with lower than 5%, compared with higher than 70% of infection rates in untreated control. The formulation showed 85 to 89% control efficacies of gray mold incidences on fruits of strawberry in pots. Pre-treatment of the agent was more effective in controlling gray mold on fruits and leaves than post-treatment at the early stage of disease development. The formulation also showed 70% control efficacy of gray mold incidence on fruits of strawberry in a field trial. The results indicate that B. subtilis S1-0210 in the wettable powder formulation may be a potential biocontrol agent to control gray mold on strawberry.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.413-420
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• 2013

The purpose of this study was to evaluate the control efficacy of major environment-friendly control agents against powdery mildew, as affected by the application condition such as disease-developing stage and microclimate, as compared with the efficacy of pesticides in plug seedling of three Cucurbitaceae vegetables, including cucumber, melon, and oriental melon. Single or combined application of major six environment-friendly control agents was used in the experiment: two biofungicide (Ampelomyces quisqualis 94013 and Bacillus subtilis Y1336), two plant extracts (neem oil and extracts of Rheum undulatum), and two mineral materials (wettable sulfur powder and lime bordeaux mixture). These control agents were treated to the plug seedlings for preventing powdery mildew and curative applications for managing powdery mildew. In all treatments, the disease incidence declined as daily average temperatures increased to $30^{\circ}C$ for consecutive 6~8 days with maximum temperature over $40^{\circ}C$. In preventative application, the control efficacy against powdery mildew was the highest in the treatment of wettable sulfur powder, and lowest in the B. subtilis Y1336, with values of 20~40%. In cucumber seedlings, the preventive single application of neem oil or wettable sulfur powder was more effective than curative application of fungicides, while the control efficacy of these agents was similar to those of fungicides in melon seedlings. The single application of R. undulatum extracts was also effective in preventing the disease for both cucumber and melon seedlings, showing a higher control efficacy than those of biofungicides during seedling stage. The treatment of water spray was not effective and showed a higher disease incidence than the untreated control plot in the oriental melon and melon seedlings. The curative application with environment friendly control agents, after powdery mildew was first detected, could not successfully controlled the disease at the middle stage (5~10% of disease incidence) of disease development. The curative combined application of [R. undulatum extracts (1st application) + wettable sulfur powder (2nd) + neem oil (3rd)] showed the highest control efficacy among the other treatments, with control value over 80% at the early stage (less than 1% of disease incidence) of disease development.

• Korean Journal of Organic Agriculture
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• v.19 no.3
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• pp.385-396
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• 2011

This study was carried out to develop environmental friendly control for major diseases and pests on Boxthorn (Lycium chinense Mill.). Outbreak of Eighteen diseases and pests were found at the Boxthorn organic yards in Chung-nam province. Among them Powdery mildew (Erysiphe polygoni de Cand.), Hypophyllous mold (Pseudocercospora chengtuensis (Tai)), Western flower trips (Frankliniella occidentalis (Pergande)), Green peach aphid (Myzus pericae (Sulzer)) and Corn earworm (Helicoverpa armigera) needed to be controled by environmental friendly methods for high fruit yield of organic Boxthorn. In summer(Jun) test Bacilus subtilis QST 713 wettable powder and Sulfur wettable powder were effective and in autumn (Sep.) test Sulfur, Copper hydroxide and Paraffinic oil were relatively effective in Powdery mildew. In Hypophyllous mold control test Paraffinic oil and Bacilus subtilis GB - 0365 were effective with above 70% control value. And it was possible to control Western flower trips by natural enemy (Orius laevigatus) by 80% control value. Corn earworm was possible to control by Bacillus thuringiensis subsp. aizawai GB413 flowable and Bacillus thuringiensis aizawa 0423 wettable powder application above 70%. And Green peach aphid was controllable with environmental friendly materials, such as, Bacillus subtilis (Seoncho), Bacillus subtilis (Jinsami) above 80% and Ginkgo nut extract above 70% control value.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.434-439
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• 2003

20세기 후반부에 이르러 초음파는 과학 및 산업분야 전반에 걸쳐 다각도로 활용 및 응용되고 있다. 본 연구는 초음파를 이용한 분무입경의 미세화 및 균일입경의 분무를 위한 초음파 응용기기의 설계를 위한 선행연구로서 초음파 에너지에 의한 고형성분의 파쇄여부를 측정하였다. 초음파 에너지를 부가한 후, 즉 초음파 처리된 상태에서의 수화제의 물리적인 파쇄특성을 광학현미경과 SEM을 이용하여 관찰하였다. (중략)

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.203-208
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• 2009

In order to elucidate the effect of spreader-stickers on the rainfastness of dithianon and chlorothalonil wettable powders, and to estimate the possibility of suggesting good new formulations, the fungicide residues on the leaf surface of hot pepper was assessed and compared after the drop-wise applications of fungicide suspensions containing spreader-sticker on leaf surface followed by artificial raining. Three commercial spreader-stickers, which were Cover, Reitron and Silwet, not only made the rainfastness of dithianon wettable powders worse on hot pepper leaf, but increasing their concentrations also accelerated it further. On the other hand, to chlorothalonil wettable powder, Reitron showed the 3-fold improvement of rainfastness. But, for the rest, there was no improvement as well. The effect of N-octylpyrrolidone (NOP) on rainfastness of both fungicides was excellent. Soybean oil formulations containing leaf-penetrable nonionic surfactant, which was either polyoxyethylene monotridecyl ether or polyoxyethylene monolauryl ether, improved dithianon rainfastness, but the ones containing conventional emulsifiers did not.

• The Plant Pathology Journal
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• v.22 no.3
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• pp.283-288
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• 2006

Trichoderma harzianum YC459 (Th 459), isolated from sawdust compost, was effective in controlling cucumber and tomato gray mold caused by Botrytis cinerea under controlled and plastic film tunnel conditions. A water suspension of the wettable powder formulation of Th 459 significantly $(P\leq0.05)$ reduced the severity of cucumber gray mold by foliar spraying at all tested concentrations from $10^5\;to\;10^8$ colony forming unit (cfu)/ml in repeated experiments. The control efficacy was maintained at least seven days with the average control value of 70% in cucumber pot tests. Mixing one to eight grams of the granular formulation ($10^8cfu/g$ dry weight) of Th 459 into one liter nursery potting mix at seeding also significantly $(P\leq0.05)$ reduced the severity of cucumber gray mold by suppression of lesion formation three weeks after treatment. Application of mixing granular formulation at seeding in combination with foliar spraying during cultivation provided a more significant reduction $(P\leq0.05)$ of cucumber gray mold than granule mixing or leaf spray alone. The foliar spraying of the formulated wettable powder of Th 459 significantly $(P\leq0.05)$ reduced the infection of tomato fruits by B. cinerea as effective as the chemical fungicide, dichlofluanid, in three plastic film tunnel experiment trials. It is suggested that effective control of gray mold of cucumber and tomato can be provided by both treatment of Th 459 into potting mix and foliar spray through induction of systemic resistance and direct inhibition of the pathogen.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.1-6
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• 1970

Cadmium pentachlorophenolxanthate has been synthesized with pentachlorophenol, carbondisulfide sodium hydroxide and cadmium chloride and its fungicidal activity was tested to Pyricularia oryzae and Cochliobolus miyabeanus. The results are summarized as followes; 1) The sample V synthesized by acidifying the crude PCP-xanthate solution at pH 8, then treated with $BaCl_2\;and\;CaC_2$ showed the highest purity, and the yield was $85.1\%$. 2) The same sample of $50\%$ wettable dust formulation inhibited conidial germination of P. oryzae and C. miyabeanus completely at 10 and 20 ppm, respectively. (Fig. 1) 3) The sample of $1.5\%$ dust formulation inhibited mycelial growth of P. oryzae and C. miyabeanus with 96 and $65\%$, respectively. The results were similar to those obtained by Ceresan calcium (Fig. 2) 4) Both dust and wettable powder formulations had no phytotoxcity on rice seedlings.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.98.1-98
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• 2003

Antagonistic effect of bacterial strains isolated from phylloplane of strawberry plants grown In greenhouse was tested on Botrytis cinerea Among the promising bacterial strains, Bacillus sp. S1-0210 showed highest inhibition of mycelial growth of B. cinerea and a broad spectrum of antifungal activities against many plant pathogenic fungi in vitro. Bacillus sp. S1-0210 was identified as Bacillus subtilis based on the analysis of 185 rDNA as well as its biochemical characteristics. Application of wettable powder formulation of B. subtiiis S1-0210 significantly reduced the incidence of gray mold on trawberry fruits during storage. Results showed that treatment of B. subtilis S1-0210 decreased the incidence of gray mold by 4.8％ whereas the incidence in control was 77.9％, indicating that the formulation of B. subtilis S1-0210 will be practically applied on strawberry fruits as a biocontrol agent of gray mold during storage.

• International Journal of Industrial Entomology and Biomaterials
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• v.21 no.1
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• pp.139-143
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• 2010

The objective of our study was the formulation of a local strain of Mamestra brassicae nucleopolyhedrovirus-K1 (MabrNPV-K1) for the development of viral insecticide to control M. brassicae. To formulate MabrNPV-K1, feeding toxicities of various supplements and ultraviolet (UV)-protection were investigated. Optical brightener Tinopal UNPA-GX (Tinopal) as UV protectant and Bentonite had some toxicity themselves to increase the mortality. The protection of polyhedra from UV light radiation was observed only by Tinopal. The MabrNPV-K1 was formulated as a wettable powder form. The mortality of the formulation was higher and rapid than that of the un-formulated. This suggested the possibility of MabrNPV-K1 formulation as an effective biological control agent for M. brassicae.