• Research in Plant Disease
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• v.9 no.3
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• pp.179-182
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• 2003

Effect of potassium phosphonate on control of potato late blight was evaluated at two fields in Jeju island. The chemical showed 82.5% control value in field located at low seacoast with 100 m elevation, while dimethomorph copper oxychloride showed 75.9 % control value. However, its control value was only 40% in another field located at mid-hilly area with 300 m elevation, in which environmental conditions of high hummudity and often rainfall were favorable to the disease development. Application intervals of the phosphonate from 7 to 15 effectively suppressed the disease and did not show statistically different control values among the spraying intervals. Results indicated that phosphonate similarly or more effectively controls potato late blight than fungicide, however, its control value could be vared according to enviromental conditions for the disease development and 15-d spraying intervals ware sufficient to suppress ther disease.

• Journal of Distribution Science
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• v.19 no.12
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• pp.91-101
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• 2021

Purpose: This study aims to explore the effects of government's value intervention messages on the prevention and control of infectious disease in the risk communication process in terms of goveremnt policy response to COVID-19 from the mismatch message perspective, and draws the relevant implicaitons. Due to the infeciton spread, some people point out that depression caused by COVID-19 is because of wrong signals of the government and infectious disease prevention and control authorities, namely value intervention messsages. Research design, data and methodology: This study examined the epidcmic situation through message deails regarding the effects of government's mismatch messages on prevention and control of infectious disease and the resulting phenomena. Results: People's lives are under serious threat overall, so the declaration of the end of COVID-19 is almost impossible unlike MERS. Economic downturn due to foreced prevention and control regulaitons of COVID-19, mistruct of social distancing, fatigue on mismatch messages, and moral hazard on the awareness of prevention and control of infectious disease are negative phenomena to risk communiaiton on COVID-19. Conclusions: This study investigated the government authorities' policy sending wrong signals due to mismatching of the reality at this point in time for infectious disease prevention and control from the risk communicaiton perspectrive.

• Journal of fish pathology
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• v.33 no.1
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• pp.97-101
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• 2020

Although aquaculture production rates grown over the years, aquatic animal diseases occur every year which causes substantial economic losses. When an aquatic animal is infected with an aquatic animal pathogen it is either incinerated or buried according to the aquatic life disease control act. Although these methods prevent the spread of disease, it is not environment friendly. Here, we developed an aquatic animal rendering equipment for disposal of fish waste which is environment-friendly and efficient. Also, fertilizer components of fish waste were evaluated value for recycling. The mobile rendering equipment was designed for field operation and/or high temperature and pressure system, oil and water separator, and shredding drying apparatus. During the experiment (July-2016 to November-2016), a total of 53,824 kg fish waste was collected, and 29,216 kg compost of rendering by-product was made. Also, compost made from viral (Viral hemorrhagic septicemia virus) infected fish did not reflect any detectable pathogen. The concentration of nitrogen, phosphorus, and organic matter in the fish waste compost were 2.17%, 26.98%, and 92.44%, respectively. The results suggest that fish waste used in this study was decomposed efficiently as per the official standard for fertilizer product. This equipment can be useful for efficient inactivation of the aquatic animal pathogenic agents and recycling of the fish waste in an environment-friendly manner.

• Korean Journal of Organic Agriculture
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• v.24 no.4
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• pp.773-786
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• 2016

Grape cultivar "Campbell Early" account for 70% of table grape in Korea and Leaf Spot Disease caused by Pseudocercospora vitis is one of a major disease in greenhouse and field grown area during late summer season in both of organic and conventional grape farm. Leaf spot disease can cause lowing of sugar content in fruit and vine growth and very difficult to control especially in organic field. Photosynthesis ability and chemical components are compared between leaf spot disease infected leaves with degree of necrotic area. With increase of disease necrotic area, $CO_2$ differential value, water use efficiency and $CO_2$ assimilation and respiration ratio are decreased proportionally and on the other hand, stomatal conductance value is not affected by disease necrotic area. Chlorophyll contents are also decreased by 50% in heavily infected leaves and imply decrease of chlorophyll contents is a major source of photosynthesis ability decline. With increase of disease necrotic area in leaves, total nitrogen and phosphate contents are decreased and on the other side, total carbon, potassium, calcium and magnesium contents are increased. From this research, we can infer that not only chemical control program is important in control of leaf spot disease but also fertilizing program is significant especially in organic agronomical control of fungal disease in grape cultivar "Campbell Early".

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.165-171
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• 2016

Platycodon grandiflorum and Codonopsis lanceolata have been considered as cash vegetables and alternative medicine plants in Korea. In a previous survey from 1998 to 2010, repeated cultivation of the plant increased root rot disease incidence and severity. The disease has been recognized as critically limiting factor for crop production. However, control method has not been established for the disease of P. grandiflorum and C. lanceolata. In this study, control efficacy of Tebuconazole EC, Trifloxystroim SC and grapefriut extract was evaluated on the root rot disease of these plants in two different field conditions. Three of different fungicide were non critical effect to the disease severity and the control value, but grapefriut seed extract (GSE) was more ability to control the disease in C. lanceolata. In most things, soil drainage was the most important to decrease the disease severity and to improve the control value.

• Research in Plant Disease
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• v.6 no.1
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• pp.39-42
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• 2000

This study was conducted to improvement of control efficiency on clubroot disease. To improve the control efficiency on clubroot disease of chinese cabbage by chemical persistent effect, Flusulfamide DP was examined with soil mixed treatment. When Flusulfamide DP was applied, the more application times, the higher control value. The control value and marketable yield per 10a of the untreated cultivation plot after two application of Flusulfamide DP were 53.9%, 4,822kg, respectively. However, based on marketability and marketable yield, untreated cultivation plot after two application of Flusulfamide DP has been thought as economic application times compared to three times application. On the other hand, the combination of soil mixing and bed soil mixing treatment Flusulfamide DP was more effective than each treatment. The control value and marketable yield of the combination treatment was 73.3∼88.9%, 5,633∼5,770kg, those of soil mixing 66.7∼70.0%, 2,847∼3,167kg, respectively.

• 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.7 no.3
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• pp.216-222
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• 2003

In order to develop effective control methods for Bakanae disease caused by Gibberella fujikuroi (Saito) Ito during rearing of rice seedlings, we investigated the disease resistance of 15 rice varieties to G. fujikuroi and control effect of six seed disinfectants, and tried to improve the using methods of the seed disinfectants. Disease resistance was tested by investigating the disease incidence on each rice cultivar grown in rice seedling box infested with or not infested with G. fujikuroi at 30 days after sowing seeds and 20 days after heading date. The results showed that Hwayongbyeo, Dongjinbyeo, Hwoanbyeo, Nonghobyeo, Nampyeongbyeo, and Hwojinbyeo were resistant G. fujikuroi, meanwhile Keulubyeo, Sobibyeo, Odaebyeo, Junambyeo, Samchonebyeo, Sangjubyeo, and Hwabongbyeo were susceptible. Three seed disinfectants, prochloraz, fludioxonil, and carproamid + thiram + fludioxonil controlled Bakanae disease of rice very well, while bonomyl + thiram, thiophanate-methyl + thiram and thiophanate-methyl + triflumizole did not suppress the disease enough. Water temperature was turned to be an important factor for controlling the disease by treating seed disinfectants. Prochloraz showed 61% control value on the disease at $10^{\circ}C$, but it showed above 95% control value at the range of $30-35^{\circ}C$. It was confirmed that the control effect of seed disinfectants increased with increasing water temperature. Meanwhile soaking period of rice seeds in the suspension of seed disinfectants and chemical dosage had no high relation to control the disease. This results suggest that rice varieties, water temperature, and optimal selection of suitable seed disinfectants are very important to control Bakanae disease effectively.

• Korean Journal of Agricultural Science
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• v.43 no.2
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• pp.153-162
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• 2016

Chilli is a widely consumed crop throughout the world. However, chilli anthracnose is a major constraint in chilli production leading to huge economic losses worldwide. Colletotrichum is a large genus of Ascomycete fungi, containing species that cause anthracnose diseases on a wide range of crops of economic value. This review is aimed at critically and accurately examining the taxonomic identification of Colletotrichum species by morphological and molecular approaches as well as assessing their management options. The use of appropriate integrated management practices, such as cultural, mechanical, chemical, and biological control, are important in chilli anthracnose disease prevention and control. Emphasis is laid on the use of biological control because it is cost effective and eco-friendly, and is an appropriate approach for disease management. The use of resistant cultivars is the cheapest, easiest, safest, and most effective means of controlling crop diseases. But, since no resistant cultivars of chilli have been developed and commercialized, it is very important to develop biological management strategies. Further studies leading to integrated disease management strategies need to be carried out.

• Research in Plant Disease
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• v.9 no.2
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• pp.72-78
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• 2003

Eight fungicides including prochloraz, tebuconazole, benomyl, mancozeb, thiophanate-methyl, azoxystrobin, and fluazinam were examined for their control effects on Fusarium bulb and root rot of oriental orchid, Cymbidium goeringii. Among the chemicals, prochloraz and tebuconazole were the most effective on suppression of the causal pathogen, F. oxysporum in vitro and on control of the disease in vivo. Prochloraz and tebuconazole inhibited mycelial growth of the fungi 95~100% at 10ppm a.i. and microconidial germination 75~100% at 100ppm a.i. Prochloraz and tebuconazole showed 80~92% and 84~88% protective control value on the disease, respectively. However, curative effects on infected orchid were relatively low. Other chemicals showed no or lower than 20% curative and 50% protective control value. Results indicated that prochloraz and tebuconazole can be used for the control of the Fusarium bulb and root rot of oriental orchids. However, the chemicals need to be applied prior to the disease development to achieve successful control efficacy.