• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.143-146
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• 2007

Concerns of entomopathogenic fungi as alternative pest control agents are increasing even though chemical pesticides have been used as the main control agents for pests and diseases in crop production. This study was conducted to test the influence of fungicides and insecticides on an isolate of Lecanicillium attenuatum that was reported to have the pathogenicity against cotton aphid, because fungicides and/or insecticides can apply with mycopesticides simultaneous, before and/or after. Fungicides fenbuconazole+thiram and propineb inhibited the spore germination and mycelial growth of L. attenuatum CS625; dimethomorph and procymidone did not affect spore germination or mycelial growth. The insecticide abamectin, deltamethrin, imidachropride, and spinosad had no detrimental effects on spore germination or mycelial growth. Therefore, these results demonstrated that careful selection of pesticides and fungicides can be applied to the integrated pest and disease control with microbial pesticide.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.128-135
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• 1985

Responses to the 14 fungicides added in PSA of penicillium expansum isolated froms the four major apple growing areas in Korea were examined. Degrees of the fungal tolerance were various with little difference by area and with great difference by kind and concentration of fungicide. Fall isolates of the fungus grew at higher fungicide concentration than did the spring isolates. $ED_{50}$ and MIC to mycelial growth of genomyl, garbenda, polydong, polyoxin and thiophanate methyl were $0.1{\mu}g-41.7{\mu}g/ml\;and\;100{\mu}g-2,250{\mu}g/ml,$, respectively, indicating high fungicide effects on the fungus isolated from decayed apples in storages and infected apples in orchards with low fungal tolerance; of captafol, captan, iprodione and mancozeb were $2.6{\mu}g - 750{\mu}g/ml\;and\;638{\mu}g-40,500{\mu}g/ml$, respectively, indicating medium degree of both fungicidal effects and fungal tolerance; and of chlorothalonil, folpet, oxidong, propineb and triademefon were $27.8{\mu}g-8,354{\mu}g/ml\;and\;2,625{\mu}g-150,357{\mu}g/ml$, respectively, indicating low fungicide effects and high fungal tolerance. Fungicidal inhibitory effects on conidia formation exhibited a similar trend as on mycelial growth whereas those on conidia germination showed an opposite trend to the mycelial growth with the exception of polyoxin and triademefon.

• The Korean Journal of Pesticide Science
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• v.7 no.1
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• pp.66-73
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• 2003

Actual pesticide usage in fruit vegetable cultivation was surveyed. Usage trend of in of vidual pesticides was evaluated to provide the data for the development of indicators of environmental impact and the production of safe agricultural products. The amount of the pesticides used for fruit vegetables was revealed in order of fungicide> insecticide> herbicide, showing that the portion of fungicide to the total amount used was about 70 to 80%. Main fungicides used on fruit vegetables were mancozeb, thiophanate-methyl propineb, etc while the insecticides were imidacloprid, milbemectin, methomyl, etc. Main formulation types of pesticide were wettable powder and emulsifiable concentrate. By different fruit vegetables and cultivation patterns, pesticide use per unit area was revealed red pepper (field cultivation, 13.2kg/ha), cucumber (field cultivation, 12.4kg/ha), sweet melon (field cultivation, 11.2kg/ha) as high pesticide use crops, meanwhile, water melon (greenhouse cultivation, 1.2kg/ha), sweet melon (greenhouse cultivation, 2.2kg/ha), strawberry (field cultivation, 2.8kg/ha) as low pesticide use crops.

• The Korean Journal of Pesticide Science
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• v.7 no.4
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• pp.258-263
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• 2003

In order to get the actual pesticide usage data for fruit crops at farmer's gate, this survey was carried out on the growers of 6 representative fruit crops such as apple, citrus, grape, peach, pear and persimmon, in Korea. One hundred fifty farmers were selected in main production areas to record their pesticide usage during the growing seasons. Pesticides were sprayed in pear 15.2 times/year and persimmon 7 times/year. Pesticide input amount per unit for fruits was 39.5 for citrus, 22.1 for apple, 21.5 for pear, 11.9 for peach, 10.8 for persimmon and 6.7 a.i. kg/ha for grape, respectively. The amounts of pesticides sprayed in 2002 except for peach and pear tend to decrease compared with those in 1999. The major fungicides used were mancozeb, propineb, dithianon, etc., while the major insecticides were fenitrothion, chlorpyrifos, methidathion, etc. Total active ingredients of pesticides used for six fruit crops amounted to 18.3% of total sales amount of pesticides for horticulture in 2002. The amounts of pesticides sprayed on citrus, grape, peach and pear in Korea was less than those in U.S.A., excepting those in apple.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.36-42
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• 2006

For the effective control of pepper anthracnose, in vitro antifungal activities of 13 commercial fungicides were tested on spore germination, mycelial growth, and sporulation of Colletotrichum gloeosporioides, anthracnose fungus. Among them, captan, chlorothalonil, dithianon, fluazinam and folpet completely inhibited the spore germination of C. gloeosporioides at the concentration of 0.8 ${\mu}g/ml$. They were followed by mancozeb and propineb, showing more than 80% inhibition of spore germination at 20 ${\mu}g/ml$. The mycelial growth of C. gloeosporioides was strongly inhibited by fluazinam and nuarimol. Except for nuarimol, most of the fungicides represented more antifungal activity on the spore germination than the mycelial growth of C. gloeosporioides. Azoxystrobin and metominostrobin, Strobilurin fungicides, were only moderately active against the spore germination and the mycelial growth of C. gloeosporioides, but they were effective antisporulant against C. gloeosporioides. From these results, control of pepper anthracnose will have achieved by preventive spray of the commercial fungicides.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.88-96
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• 2008

To obtain protoplasts of Colletotrichum acutatum JC24, conidia were inoculated onto cellophane membrane placed on PDA and incubated at $25^{\circ}C$ for 20 hrs under the dark condition. Cellophane membranes, where mycelia were incubated, were soaked into 2% lysing enzyme solution prepared with 0.02 M phosphate buffer (pH 7.0) including 1.2 M sorbitiol. After treatment in 2% enzyme solution for 2 - 3 hrs, it could be possible to harvest $2-3\;{\times}\;10^6$ protoplasts/mL. The effect of several fungicides on reversion ratio was determined by using the protoplasts obtained from C. acutatum JC24. Any protoplasts could not be reversed to mycelia on reversion PDA amended with $10\;{\mu}\;g\;mL^{-1}$ of propineb. With tebuconazole, inhibition ratio of protoplast reversion was 100 and 0.9% at 0.5 and $0.1\;{\mu}\;g\;mL^{-1}$, respectively, while inhibitory effect on mycelial growth was 85.1 and 75.7%. The inhibitory tendency of carbendazim on protoplast reversion was as same as mycelial growth. In the case of strobilurins, trifloxystrobin and kresoxim-methyl, they only could inhibit protoplast reversion of C. acutatum JC24, when salicylhydroxamic acid (SHAM) was amended into reversion PDA with strobilurins.

• Research in Plant Disease
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• v.17 no.2
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• pp.121-128
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• 2011

Bacteriolytic myxobacteria have been known to secrete various antifungal metabolites against several soilborne phytopathogens including Phytophthora. Among the three isolates of Myxococcus spp., KYC 1126 and KYC 1136 perfectly inhibited the mycelial growth of Phytophtora capsici in vitro. In order to show the biocontrol activity on Phytophthora blight of hot pepper, we tried to find the best way of application of a myxobacterial isolate. Although KYC 1126 fruiting body was easily grown on the colony of Escherichia coli as a nutrient source, it did not control the disease when it was pre-applied in soil. Before the bioassay of a liquid culture filtrate of KYC 1126 was conducted, its antifungal activity was confirmed on the seedlings applying with the mixture of the pathogen's zoospore suspension and KYC 1126 filtrate. On greenhouse experiments with five and four replications, the control value of KYC 1126 on phyllosphere and rhizosphere was 88% and 36%, respectively. Whereas, the control value of dimetnomorph+propineb on phyllosphere was 100% and that of propamorcarb on rhizosphere was 44%. There was a phytotoxicity of the myxobacterial filtrate when seedlings were washed and soaked for 24 hours. Gummy materials were covered with roots. And stem and petiole were constricted, then a whole seedling was eventually blighted.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.232-237
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• 1996

Toxicity of 5 acaricides, 4 insecticides. and 6 fungicides to the twospotted spider mite, Tetranychus urticae Koch, and its predator Amblyseius womersleyi Schicha was assessed in a laboratory using a leaf disk bioassay. Dicofol was equally very toxic to aduly females of T. urticae and A. womersleyi, and caused 46% and 40% mortality of eggs of those two species, respectively. Adult females of A. womersleyi dipped in Abamectin solution showed low mortality(16.6%), while all T. urticae females died within 24 hours after dipping. Three ovicidal acaricides (Tetradifon, Clofentezine, and Hexythiazox) showed no mortality of predator eggs, but more than 90% mortality of T. urticae eggs. Four insecticides (Teflubenzuron, Triflumuron, Diflubenzuron, and Imidacloprid) and three fungicides (Propineb, Fenarimol, and Polyoxin-B captan) were non toxic to the A. womersleyi adult females. The other fungicides (Chlorothalonil, Nuarimol.Mancozeb, and Folpet) were a little toxic to adult females of the predator, showing$\leq$23.3% mortality, It may be suggested from these results that 4 insecticides, 4 acaricides, and 6 fungicides described could be incorporated into the integrated pest management system with A. womersleyi in apple orchard.

• Research in Plant Disease
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• v.11 no.2
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• pp.185-192
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• 2005

In 1999 and 2002, 130 and 258 isolates of Colletotrichum spp. causing red pepper anthracnose were obtained from infected red pepper fruits, respectively. Their responses to 4 protective and 3 ergosterol biosynthesis-inhibiting(EBI) fungicides were investigated by observing their mycelial growth on PDA incorporated with different concentrations of each fungicide. The Colletotrichum isolates obtained in 1999 showed higher $EC_{50}$ values than those isolated in 2002 against three protective fungicides such as dithianon, chlorothalonil, and propineb, whereas the response was reversed toward other protective fungicide, iminoctadine. On the other hand, the isolates of year 1999 were more resistant against three EBI fungicides such as tebuconazole, hexaconazole, and prochloraz than those of year 2002; the $EC_{50}$ values of the former were 1.2-4.4 times higher than those of the latter, The responses of the Colletotrichum isolates toward protective and EBI fungicides were fluctuated according to regions, where the infected fruits were collected. On the other hand, the resis tance of Colletotrichum isolates to protective fungicides increased during monitoring from July to September, However, their responses towards EBI fungicides were not changed.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.51-59
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• 2005

Korean maximum residue limits (MRLs) for pesticides have been established based on scientific data of good agricultural practice, acceptable daily intake (ADI), food intake, average body weight and others. MRLs for pesticides are generally set under the principle that theoretical maximum daily intake (TMDI) are always below ADI. As results, 104 MRLs are going to be newly established for 24 pesticides and 102 MRLs are going to be added for 63 pesticides that have regulation already, Among new pesticides, ethaboxam and flupyrazofos are effective components that are first developed in Korea. In case of dithiocarbamates, MRLs are classified by 3 groups such as dimethyldithiocarbamates, ethylenebis (dithiocarbamate)s and propineb.