• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.160-165
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• 2011

BACKGROUND: This study carried out to fate of pesticide and investigate worker exposure of pesticide in air after applying granular type pesticide formulation on soil in greenhouse for preventing farmer's pesticide intoxication. METHODS AND RESULTS: The recovery of pesticide, cadusafos, ethoprophos and probenazole on absorbent in air were ranged 80.9~121.1% in charcoal and 90.6~99.0% in XAD-4, respectively. Emission rate of in lysimeter was higher 3~5 times than that of pesticides from topsoil not added water at $35^{\circ}C$ plot after applying a mixture of granular formulation and soil. The ethoprophos concentration in air, 50 cm high from soil surface at greenhouse, was reached the highest 186.4 ${\mu}g/m^3$ within 13 hours and were ranged 17.8~186.4 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 150 g a.i./245 $m^2$. The cadusafos concentration in air at greenhouse was reached the highest 37.3 ${\mu}g/m^3$ within 39 hours and were ranged 10.0~37.3 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 180 g a.i./245 $m^2$. The probenazole concentration in air at greenhouse was reached the highest 1.45 ${\mu}g/m^3$ within 37 hours and were ranged 0.23~1.45 ${\mu}g/m^3$ during 46 hours after applying granular formulation at dose rate 144 g a.i./245 $m^2$. CONCLUSION(s): The result of the reentry interval study demonstrated that reentry intervals for ethoprophos and cadusafos are longer than 48 hours.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.96-103
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• 1993

The experiments on the ecological characteristics of the suspensible green algae and the algae causing soil-flakes and shier chemical control were conducted in 1992. The unicellular green algae which were dominated by Chlamydomonas sp. largely occurred when phosphorus was applied, but which were reduced by nitrogen application. The filamentous green algae which were dominated by Klebsormidium sp. largely occurred when phosphorus was applied, and which much more increased when nitrogen or potassium was combined with phosphorus. The suspensible green algae which were dominated by Klebsormidium sp. were controlled by 60-70% when simazine 10g ai/10a and propanil 105g ai/10a were applied. The dark blue soil-flakes largely occurred at nitrogen application, and which much more increased when nitrogen was combined with phosphorus. The dark brown soil-flakes largely occurred at phosphorus application, but no more increased even if nitrogen or potassium was combined with phosphorus. The dark blue soil-flakes which were dominated by Oscillatoria sp. much more increased at the temperature conditions of $18^{\circ}C$ compared with $24^{\circ}C$ and $29^{\circ}C$. The applications of bensulfuron/mefenacet/dymron, piperophos/dimethametryn and bensulfuron/dimepiperate controlled 70-90% of the dark blue soil-flakes.

• Korean journal of applied entomology
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• v.9 no.1
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• pp.25-32
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• 1970

This experiment was conducted to find out the simultaneous control effect of granulated insecticides on the several major rice insect pests in Korea. The granulated insecticides used were Terracur P$5\%$ (one of the phosphoric insecticides), Lebaycid $5\%$, and Sang-gamma (gamma-BHC) $6\%$. Those insecticides were broadcasted by hand on the paddy field at the ratio of 3kg. in June and 4kg. in August per 10 a, and the date of insecticidal application was based on the maximum moth occurrence of the rice stem borer in 1969. The rice insect pests tested in this study were rice stem borer (Chilo suppressalis W.), green rice leafhopper (Nephotettix bipunctatus cincticeps U.), smiller brown planthopper (Laodelphax striatellus F.), and white back planthopper (Sogotella furcifera H.). For the study of residual effectiveness of the insecticides, the rice stem borer larvae just hatched from the eggs were installed on the sheath of rice plants collected from the paddy field after insecticidal treatment, and the mortality was made at 48 hours after installation. High mortality was observed in Terracur P and Sang-gamma treatments and low mortality in Lebaycid treatment. The duration of residual effects giving about 50% mortality was about 14 days in Sang-gamma and about 6 days in Terracur P treatments. The study on the effectiveness of the insecticides to the rice stem borer in the paddy field was made by the number of dead blades and white heads of the rice plants injured by the larvae, and the number of survival larvae in the straws after crop harvest. The order of insecticidal effectiveness to the rice stem borer was Terracur P=Sang-gamm>Lebaycid. The study on the effectiveness of the insecticides to the leafhoppers and planthoppers in the paddy field was made by the population density by sweeping (5 times) at the given day intervals after treatments. Terracur P was highly effective for the control of the green rice leafhoppers and Lebaycid was moderately effective, but Sang-gamma seemed not to be effective. The effectiveness of the insecticides tested to the planthoppers was not clear, and it seemed to related with the low insect population density. Study on the determination of proper timing of insecticidal application was not also made clear, and it seemed to be short in the range of day intervals in the insecticidal application. For the study on the control effects of the rice insect pests, rice yield per 100 hills per plot was observed. There was no statistically significant difference among the treatments in rice yields, but the order of yield (Terracur P>Sang-gamma>Lebaycid>Control) was paralleled with the tends of control effects above mentioned. In a view point of simultaneous control of the rice stem borers and green rice leafhoppers by the application of granulated insecticides, Terracur P and Lebaycid were more effective than Sang-gamma which have been used.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.83-88
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• 2001

Residual effect of imidacloprid on brown planthopper (BPH) and residues on rice plant were investigated in pot and field tests. Residual effect (showing 100% mortality) of imidacloprid of granule formulation on the BPH lasted for 40 days at a recommended dose (0.3 kg a.i./ha) and for 30 and 20 days at a half and a quarter of the recommended dose, respectively. In case of liquid formulation of imidacloprid, the residual effect lasted for 40 days at both recommended dose (0.032 kg a.i.1ha) and a half of it, and lasted for 30 days at a quarter of it. The next generation formation of BPH was throughly depressed by the imidacloprid application at the former generation. This result supports the residual effect of imidacloprid on BPH. Seed dressing (3 ghg) showed insecticidal activity (96.7% mortality) for 55 days after treatment. When granule formulation of imidacloprid was applied to soil at a recommended dose , imidacloprid residue in leaves of rice plant increased up to 0.46 ppd for 6 days and then decreased to 0.09 ppm on 40 days after application. Residue of imidacloprid in leaves of rice plant increased up to about 0.23 ppm and about 0.2 ppm for 6 days when applied at a half and a quarter of the recommended dose, respectively and after that they decreased.

• Korean Journal of Environmental Agriculture
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• v.20 no.4
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• pp.269-276
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• 2001

Several experiments including persistence, distribution, leaching, and terminal residue trials were carried out to investigate the behavior of cyclosulfamuron in rice paddies. Cyclosulfamuron was gradually dissipated in two different soils showing the first-order kinetics. Half-lives of the herbicide were calculated to be $17{\sim}30$ and $14{\sim}16$ days under field and laboratory conditions, respectively. In the paddy soil/water system, the residue tended to reside more in the soil phase as time elapsed. Cyclosulfamuron was less persistent in paddy water than in soil with half-lives of 10 and 19 days, respectively. No cyclosulfamuron was leached below 20 cm-deep soil during water percolation with 50 cm hydraulic head, while some downward mobility was observed within the soil column. When EC and SC formulations of cyclosulfamuron were applied to the paddy field at 120 or 150-day pre-harvest intervals, its terminal residues in hulled rice were all less than 0.01 mg/kg, irrespective of formulation type and application timing. In rice straw, however, some residues were found at $<0.02{\sim}0.05$ mg/kg as SC formulation was applied. Rapid dissipation, restricted mobility, and low terminal residues of cyclosulfamuron in rice paddies suggest that no significant residues would be transported or carried over to the non-target environment.

• Korean Journal of Weed Science
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• v.14 no.4
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• pp.272-279
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• 1994

In order to compare the biological properties of benfuresate and cinosulfuron as herbicides for the chemical control of Eleocharis kuroguwai, some experiments were conducted at greenhouse and field conditions in 1993. Benfuresate and cinosufuron moved to 2cm and 6cm deep in paddy soil and inhibited the growth of E. kuroguwai. Benfuresate was absorbed into the roots of E. kuroguwai. whereas cinosulfuron was absorbed into not only the roots and shoots but also the mesocotyls. After the emergence was inhibited by the soil application of herbicides, the percentage of regrowing numbers was higher at cinosulfuron than at benfuresate, whereas the growth rate was higher at benfuresate on the contrary. Benfuresate brought about complete death of buds as a killing type, but cinosulfuron produced lots of abnormal shoots as an inhibiting type. Benfuresate was able to apply on soil surface from the preemergence to the early stage of 2cm high, but cinosulfuron was able to use from the preemergence to the stage of 15cm high. The foliar application of cinosulfuron showed a good control effect, but it induced a severe phytotoxicity to rice. A good control effect of Benfuresate/bensulfuron GR lowered at the late stage, but that of cinosulfuron/mefenacet/dymron GR at the early stage maintained until the late stage of 65 days after transplanting.

• Korean journal of applied entomology
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• v.47 no.1
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• pp.101-105
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• 2008

Effects of different application of nematicides (fosthiazate 5% G, ethoprophos 5% G, and diazinon 34% EC) for the control of Aphelenchoides fragariae in strawberry were evaluated in a greenhouse experiments. Mother strawberry (Fragaria grandiflora) cv. Yeohong were dipped in solution of nematicides (fosthiazate or ethoprophos at 2.5 g a.i./liter in $20^{\circ}C\;or\;46^{\circ}C$) for 10 min. and planted in a greenhouse for dipping treatment. For the compare, mother strawberry were dipped in hot water for 10 min. without chemicals. For soil treatment, fosthiazate or ethoprophos at 3 kg a.i./ha were mixed into soil. For foliar spray, diazinon at 3.4 g a.i./liter was sprayed at foliage until runoff. At 40, 80, and 100 days after planting, runners were harvested from each treatment and the rate of nematode infestation and the number of nematodes per plant were examined. After 100 days of planting, mother strawberry plants dipped in fosthiazate solution (2.5 g a.i./liter, $20^{\circ}C$) for 10 min. produced more number of healthy runners and reduced % of infected runner as much as 90% and also had fewer nematodes per runner. Fosthiazate was more effective than ethoprophos. Foliar application of diazinon was reduced A. fragariae populations only in early season. Hot water treatment and nematicide soil treatment were less effective.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.79-84
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• 1998

This study was conducted to obtain information on occurrance ecology of Aneilema keisak Hassk. and establish its effective control system in direct-seeded rice. Optimum germination temperature and storage temperature to break dormancy were $22^{\circ}C$ and $4^{\circ}C$, respectively. Optimum content of soil moisture for germination was 35%(w/w) in clay loam soil, where recorded 85% of germination rate. In the inter-specific competition between density of Aneilema keisak Hassk. and constant rice-mixed stands, the plant height and the tiller of rice were decreased with increase of density of Aneilema keisak Hassk. Among the herbicides tested, piperophos+dimethametryn(8.2+2.2 g ai/10a) GR and. pyrazosulfuron-ethyl+mefenacet(2.1 + 105 g ai/10g) GR were found to be effective for control of Aneilema keisak Hassk., having more herbicidal effect with an earlier application.

• Korean journal of applied entomology
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• v.3
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• pp.41-44
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• 1964

1. This experiment was planned to compare the effectiveness of Diazinon granular and gammadol dust with the low toxic organophosphorus insecticides applied on the water-surface for the control of the rice stem borer, Chilo suppressalis Walker, in the 2 nd generation and to determine the proper timing of those insecticidal applications at Suwon, Korea, in 1964. 2. The hatching larvae from the eggs were inoculated on the rice plants in pots and insecticides were applied on the water-surface of pots at a given day intervals. The dose of insecticides used per pot was calculated from the 120g. as a actual ingredient per 10 a. The number of living larvae was observed at the 20 days later from the inoculation (as shown in Table 1.). 3. As shown in Table 2 and 3, there was highly significance between the chemicals and L.S.D. was 24.22. The best effectiveness was Diazinon granular and 2nd was gamma-dol dust. The organophosphorus emulsion concentrations used in this experiment were less effective than two other insecticides. Although there were some suspicious results according to the day intervals inoculated, the order of effectiveness was Diazinon>gamma-dol>Sumithion>EM>EPN> Cidial as the total moan. 4, As shown in Table 2 and 3, there was no significance between the timing of insecticidal applications, but, m the whole, Diazinon granular was most effective at a given day intervals in this experiment and gamma-dol also was effective at the day Plot inoculated. The proper timing of EPN, EM, and Cidial seemed to be at e day plot inoculated and that of Sumithion at the day plot before inoculation.

• Research in Plant Disease
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• v.11 no.1
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• pp.43-47
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• 2005

To investigate control efficacy of flusulfamide GR (granule) on Chinese cabbage clubroot caused by Plasmodiophora brassicae, experiment was accomplished in field located in Gangneungshi alpine area contaminated by P. brassicae. Flusulfamide GR provided control value of 84.6% and that was statistically significant difference from standard fungicides containing untreated control. To investigate ratio of reduction of resting spore according to fungicide treatment, soil of Chinese cabbage field before and after fungicide treatment were sampled and investigated density of resting spore. Resting spore density was not uniform in soil before fungicide treatment. Therefore, to investigate control efficacy of fungicide against clubroot, investigation on resting spore density was conducted before experiment and reflected in experimental design. Flusulfamide GR and DP (dust powder) provided 64.2% and 63.7% of reduction of resting spore on field soil after fungicide treatments. This result indicated that control efficacy of the fungicides was correlated with reduction of resting spore of P. brassicae. The increasing rate in fresh weight of above-ground part of Chinese cabbage by flusulfamide DP and GR, fluazinam DP and trifloxystrobin SC (suspension concentrate) was 14.3%, 13.0%, 13.8% and 3.8%, respectively. From above result, flusulmide GR have outstanding control efficacy against clubroot of Chinese cabbage and is effectively decreasing of resting spore density in soil.