• The Korean Journal of Pesticide Science
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• v.16 no.2
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• pp.131-136
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• 2012

This study was carried out to elucidate residual characteristics of azoxystrobin and difenoconazole in fresh ginseng. Test pesticides were sprayed onto ginseng both in 2009 for 3-year-old ginseng and in 2010 for 4-year-old ginseng according to their pre-harvest intervals (PHIs). Limit of quantitation (LOQ) of both azoxystrobin and difenoconazole was 0.003 mg/kg. Analytical methods set up for the test pesticides were considered to be suitable for the analysis of their residues in fresh ginseng, considering that their recoveries ranged from 87.58 to 112.79%. Concentration of azoxystrobin in 3-year-old ginseng ranged from 0.004 to 0.011 mg/kg and that in 4-year-old ginseng ranged from 0.007 to 0.016 mg/kg. Amounts of difenoconazole in 3- and 4-year-old ginsengs were from 0.003 to 0.007 and from 0.007 to 0.01 mg/kg, respectively, representing no accumulation effect observed in residue amount between them.

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.35-42
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• 2012

This study was carried out to elucidate the residual characteristics and calculate processing factors of difenoconazole in ginseng and its processed products, such as dried ginseng, red ginseng and their water and alcohol extracts. The pesticide was sprayed onto the ginseng according to its pre-harvest intervals in 2009 (four-year-old ginseng) and 2010 (five-year-old ginseng). Harvested ginseng was processed to dried ginseng, red ginseng and their extracts according to the commercially well-qualified conventional methods provided by the Korea Ginseng Corporation. Limit of detection (LOD) and limit of quantitation (LOQ) of difenoconazole in fresh ginseng were 0.001 and 0.003 mg/kg, respectively. In case of processed ginseng products, their levels were 0.002 and 0.007 mg/kg, respectively. Concentration of difenoconazole in both fresh ginseng and its processed products increased with the experimental period. Processing factors, calculated as a ratio of difenoconazole concentration in processed products to fresh ginseng were found to be 1.71 to 2.17 and 1.62 to 2.03 in case of dried and red ginseng, respectively, while those for their extracts ranged from 1.76 to 2.98. In case of five-year-old dried ginseng and red ginseng as well as their extracts, the ranges of processing factor of difenoconazole were found to be 2.9 to 3.1, 1.9 to 2.2 and 2.4 to 4.7, respectively.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.249-255
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• 2009

In order to calculate the processing and reduction factor between fresh and dry Welsh onion which was widely used as a dried agricultural ingredient of food in Korea. 7 pesticides such as pyridalyl, kresoxim-methyl, spinosad, flufenoxuron, difenoconazole, metconazole, and tebufenozide were tested. After 2 sites field trial conducted and measured water contents by drying at $60^{\circ}C$ and analyzed the pesticide residue. Water contents of fresh and dried Welsh onion are 89.2 and 10.2% respectively. Averages of processing factor showed 7.24 of pyridalyl, 2.85 of kresoxim-methyl, 7.43 of spinosad, 3.17 of flufenoxuron, 4.38 of difenoconazole, 2.40 of metconazole and 8.13 of tebufenozide into 2 field samples. Averages of Reduction factor showed 0.87 of pyridalyl, 0.35 of kresoxim-methyl, 0.88 of spinosad, 0.38 of flufenoxuron, 0.52 of difenoconazole, 0.29 of metconazole and 0.98 of tebufenozide. Residual amounts of pesticides in/on fresh Welsh onion reduced during drying process.

• Korean Journal of Medicinal Crop Science
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• v.16 no.6
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• pp.390-396
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• 2008

The aim of this work is to assess the safety of fungicide tolclofos-methyl, difenoconazole and azoxystrobin in ginseng sprayed by safe use guideline. When tolclofos-methyl was sprayed on ginseng by safe use guideline, the residue amounts (MRL) of it in ginseng was 0.13 mg/kg which is below than 0.3 mg/kg, maximum residue limit established by Korea Food & Drug Administration (KFDA). The residue amounts of ginseng parts, head part was 0.37 mg/kg and main body part was 0.13 mg/kg. In case of difenoconazole, the residue amounts in ginseng was 0.81 mg/kg. which was exceed the MRL, 0.2 mg/kg. By the analyze results of ginseng part, the residues of head and main body part were 3.01 and 0.40 mg/kg, respectively. In experiment of vinyl mulching, the residue amount of difenoconazole in ginseng was 0.05 mg/kg. The residue amounts of azoxystrobin in ginseng sprayed by safe use guideline was 0.14 mg/kg. This residue was not exceed the MRL 0.5 mg/kg. The residue amounts by ginseng parts was 0.51 mg/kg for head part and 0.28 mg/kg for main body part. In case of vinyl mulching, the residue amount of azoxystrobin was 0.02 mg/kg.

• Proceedings of the Korean Society of Life Science Conference
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• 2008.10a
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• pp.59.1-59.1
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• 2008

• Horticultural Science & Technology
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• v.18 no.6
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• pp.827-833
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• 2000

This study was carried out to investigate the effect of plant growth retardants (daminozide, chlormequat, uniconazole, paclobutrazole) and fungicides of triazole chemical (hexaconazole, microbutanil, difenoconazole, terbuconazole, bitertanol) on the growh of 'New Guinea' impatiens. Plant height and canopy were decreased by all kinds of plant growth retardants tested in both 'Anguilla' and 'Papete'. Especially, uniconazole and paclobutrazole were most effective in inhibition of top growth. However, the content of chlorophyll increased at all treatments of plant growth retardants and stem diameter tended to be increased at the highest concentration of all kinds of plant growth retardants tested. The results in all cultivars tested, with the experiment of triazole fungicides, were similar to the results of experiment with plant growth retardants. These results suggest that fungicides of triazole chemical such as hexaconazole, microbutanil, difenoconazole, terbuconazole and bitertanol can be used for the promotion of quality in potted 'New Guinea' impatiens.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.179-188
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• 2006

The toxicities of 37 commercial pesticides for citrus pests were evaluated to H, fallacis. Eight fungicides (difenoconazole, imibenconazole, azoxystrobin, dithianon, fluazinam, procymidon, streptomycin, tribasic copper sulfate), three insecticides (dichlovos, imidacloprid, thiamethoxam) and four acaricides (milbemectin, tetradifon, dicofol, spirodiclofen) had lower effect to the hatchability of eggs N. fallacis. Six fungicides (propineb, difenoconazole, imibenconazole, azoxystrobin, dithianon, procymidon) and three acaricides (bifenazate, tetradifon, spirodiclofen) showed lower contact toxicity to adult N. fallacis. The secondary toxicity of 26 pesticides to N. fallacis adult were evaluated. Two fungicides (fluazinam, streptomycin) and 3 acaricides (machine oil, cyhexatin, halfenprox) showed low toxicity when the prey (eggs of spider mite) was treated with pesticides.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.112-116
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• 2013

The aim of the present study was to isolate phosphate solubilizing bacteria (PSB) and to assess their potential tolerance to fungicides. Out of thirty PSB, two strains Klebsiella oxytoca and Enterobacter ludwigii were selected on the basis of their tolerance to fungicides. Both strains were assessed for their phosphate solubilizing ability using three different fungicides (difenoconazole, fluazinam and streptomycin) each with the concentrations of 0, 1, 2 or 3 times of the recommended rate. Both strains showed increased phosphate solubilization with difenoconazole at 1, 2 and 3 times of the recommended rate as compared to the phosphate solubilization of the control. The phosphate solubilization in Klebsiella oxytoca was recorded as 326, 538, 518 and 481 ${\mu}g\;mL^{-1}$ at 0, 1, 2 and 3 times of the recommended rate respectively, whereas in Enterobacter ludwigii it was recorded as 395, 499, 529 and 533 ${\mu}g\;mL^{-1}$ respectively at various doses. Based on the present findings, it may be concluded that both strains have the potential to be used as bio-inoculants which can solubilize phosphate even at the higher doses as compared to the recommended rate of fungicides.

• Korean Journal of Environmental Agriculture
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• v.36 no.2
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• pp.80-86
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• 2017

BACKGROUND: Pesticides is exposed in an aquatic environment and effected to benthic animals. Especially, sediment-associated pesticides is required for determination of sediment toxicity on aquatic organisms. This study was conducted to evaluate the impact of six pesticides (chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil, pendimethalin) on Chironomus riparius in aquatic ecosystems. METHODS AND RESULTS: Chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil and pendimethalin were used as a model compounds, which have a sediment-associated potential ($K_{oc}$>3). Acute and chronic toxicity tests on Chironomus riparius were performed at six concentrations of each pesticide with four replicates of each based on OECD test guideline 235 and 218. The calculated 48-h $EC_{50}$ values of chlorfluazuron, flutianil, pendimethalin, difenoconazole, dithianon and flufenoxuron were 6.72, 2.55, 2.27, 0.77, 0.30 and 0.11 mg/L, respectively. Flufenoxuron was the lowest 48-h $EC_{50}$ value in this study. The No Observed Effective Concentration (NOEC) and the Lowest Observed Effect Concentration (LOEC) of flufenoxuron for Chironomus riparius in 28-days test were 30 and $60{\mu}g/kg$, respectively. CONCLUSION: Pesticides of the sediment-associated have the potential effect for Chironomus riparius in aquatic ecosystems. Therefore, sediment toxicity assessment of these pesticides should be further investigated to evaluate the impact to benthic organisms.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.823-826
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• 2000

This study was carried out to investigate the effect of plant growth retardants (daminozide, chlormequat, hexaconazole, uniconazole, paclobutrazole) and fungicides of triazole chemical (microbutanil, difenoconazole, terbuconazole, bitertanol) on the rooting of 'New Guinea' impatiens cuttings. In both 'Papete' and 'Anguilla', the formation of adventitious roots was promoted by all concentrations of chlormequat, hexaconazole, uniconazole, and paclobutrazole treated. More adventitious roots were formed with hexaconazole, uniconazole, and paclobutrazole than with chlormequat. Length of the longest root and rooting zone decreased at higher concentrations of chlormequat, hexaconazole, uniconazole, and paclobutrazole in 'Papete', while 'Anguilla' showed less responses. In contrast with plant growth retardants, the formation of adventitious roots was remarkably promoted by fungicides of triazole chemical such as microbutanil, difenoconazole, terbuconazole, and bitertanol in 'Pepete' and 'Martinique' impatiens, but was not in 'Pagopago'. However, length of the longest root and rooting zone showed more sensitive response in 'Martinique' and 'Pagopago' than in 'Pepete'. These results suggest that fungicides of triazole chemical can be effectively used for rooting promotion of impatiens cuttings.