• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.53-58
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• 1998

In order to minimize harmful side effects, extend weed control performance, and control the releasing rate of the active ingredient, dicamba controlled release granular formulations were prepared with starch as matrix. Leaching, soil residue, and volatilization of the granules were compared with dicamba soluble concentrate formulation (SL). Leaching of dicamba through the soil applied with the granules could be reduced more than 50% as compared with that of dicamba SL. The half life of dicamba in loamy soil treated with the granules was 50 to 51 days, while that in sand loamy soil was 50 to 58 days. Whereas, the half life of dicamba in loamy and sand loamy soil applied with dicamba SL was 24 and 22 days, respectively. Volatilization of dicamba from the granules was 10 times less than that of dicamba SL.

• Korean journal of applied entomology
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• v.26 no.1 s.70
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• pp.9-12
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• 1987

The control effect of three systemic insecticides on the brown planthopper; carbofuran 3G, disyston 3G, and omethoate 50% EC, which have been used to control of the insect pests on rice crop in its early growing season, were evaluated. Soil incorporation and water broadcasting methods before transplanation were used for carbofuran and disyston, and omethoate was applied as foliar spray 6 days after transplanation. Ten pairs of newly emerged adults were inoculated on June 11, 21, July 2, 11, and 25. The number of the brown planthoppers on the rice plane were examined by means of direct reading. The three insecticides were effective for about ten days regardless of application methods, thereafter, fail to control of the insects except carbofuran. By means of soil incorporation, carbofuran could control the insects effectively for 45 days or longer, and it seemed to be able to control the progeny of the migrated brown planthopper until middle or late June.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.37-45
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• 1999

Dicamba (3,6-dichloro-o-anisic acid) granular formulations for controlled release (DGFCRs) were prepared with biodegradable polymers, corn starch and pregelatinized starch, to minimize harmful side effects, extend weed control performance, and control the releasing rate of the active ingredient. Physico-chemical properties and biological activity of DGFCRs were studied. Six different granules were formulated by applying two processes, granulation and extrusion. Formulation efficiencies of active ingredient (A.I.) in the granules prepared by granulating and extruding were $90.0{\sim}96.3%$. Incorporation ratios of A.I. in the granules prepared by granulating and extruding showed $89.5{\sim}94.5%$ and $46.7{\sim}82.0%$, respectively. The highest swellability was DG-2 formulation prepared with corn starch. Whereas, the lowest floatability in water was DG-2 formulation, while the highest one was DG-1 formulation prepared with pregelatinized starch, Miragel 463. The degradation rates of dicamba in the granules under the elevated temperature of $50^{\circ}C$ were less than 5% for DG-1 and DG-2 formulations even after 90 days, meanwhile, those of DE-1 formulations prepared with pregelatinized starch, Mirasperse, were more than 5%. The release rates of A.I. from the granules into water under a static condition were about 100% after 2 weeks. Weeding effects of the granules on broad leaf weeds tested in greenhouse were more than 90% after 30 days.

• Journal of Bio-Environment Control
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• v.17 no.4
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• pp.330-335
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• 2008

This experiment was carried out to investigate the effects of insecticide control system in eggplant greenhouse. In all treatments, the average densities of Frankliniella occidentalis and Tetranychus urticae were $0.3{\sim}1.8$ and 0.0 per leaf at 28 days after treatment, respectively. These results indicate the alternate application of Abamectin EC and Spinosad GW can be useful in control for F. occidentalis and T. urticae in eggplant greenhouse. The density suppression effect against Liriomyza trifolii and Trialeurodes vaporariorum was maintained for 28 days after treatment, but control effect was low at 28 days after treatment.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.17-23
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• 2003

최근 채소작물의 모종은 주로 플러그 육묘방식으로 생산되고 있다. 플러그묘는 단위면적당 많은 개체 수를 육묘할 수 있고, 일련의 작업을 기계화할 수 있으며 운반이나 취급이 용이하는 등 여러 가지 잇점이 있으나 제한된 용적에 밀식되므로 묘가 연약하고 도장되기 쉬운 문제점이 있다(Bae, 1999; Choi, 2002). 이러한 도장 및 과번무 억제를 위해서 대부분의 육묘장에서는 화학적 생장억제제로를 처리하고 있는데 이는 정식한 이후에도 약효의 지속되기 때문에 초기생육을 지연시키거나 생식생장에 부정적인 영향을 미칠 수 있다(Gent, 1997). (중략)

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.231-243
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• 2002

Starting with linear free energy relationships (LFER), drug design to mimic of the activated complexes at transition state, and hydrolysis mechanisms to control the potency and residual properties of pesticides were introduced and summarized for the necessity. In order to understand the searching or development of new agrochemicals by two dimensional quantitative structure-activity relationship (2D QSAR) methodology, a series of the various descriptors, steric constants, electronic constants including quantum pharmacological parameters and hydrophobic constants were classified and discussed for results of the several studied cases. In addition, the processes of development of new agrochemicals by QSAR techniques were introduced simply.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.256-261
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• 1997

Effect of a new postemergence herbicide carfentrazone-ethyl on controlling weeds in pear orchards was examined and compared with that of glyphosate and glufosinate. Herbicides tested were applied in mid June when weeds had reached at an average height of 15 to 20cm. The experimented orchards were infested mainly by dicots of Artemisia princeps, Chenopodium album, Polygonum hydropiper, Erigeron canadensis, Commelina cummunis, Calystegia japonica, and Amaranthus ascenders, and monocots of Echinochlor crus-galli, Digitaria sangunalis, Setaria viridis, and several sedges, Carfentrazone-ethyl alone effectively controlled dicot weeds in the orchards, but not monocot weeds. Especially, sedges were not adequately controlled by carfentrazone-ethyl alone at any application rates examined. Glyphosate or glufosinate was more effective to control monocot weeds than carfentrazone-ethyl, whereas carfentrazone-ethyl exhibited higher effect on dicot weeds than glyphosate or glufosinate. Carfentrazone-ethyl mixed with glyphosate of the half recommended rate exhibited a higher degree of weed control, especially of E. crus-galli, as compared to the herbicide mixture of carfentrazone-ethyl with glufosinate of the half recommended rate. However, no phytotocixity of the herbicides to pear trees was observed. Our results demonstrate that catfentrazone-ethyl is useful to reduce the application rates and to accelerate the weed controlling effect of glyphosate or glufosinate. Thus, carfentrazone-ethyl in combination with glyphosate or glufosinate can successfully be used to control the most important weeds in orchards.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.242-248
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• 2023

This study was conducted to evaluate the effects of trinexapac-ethyl (TE) and prohexadione-calcium (PC) on the growth and turf quality of perennial ryegrass (Lolium perenne L.). Treatments were designed as follows; control (non-treatment), TE (TE 0.01 a.i. g·m^-2·100mL^-1), and PC (PC 0.01 a.i. g·m^-2·100mL^-1). Compared with control, turf color index and chlorophyll content of TE and PC treatments were not significantly different. As applied plant growth regulators (PGRs), shoot length in the TE and PC was decreased by 8.9-12.4% and 6.7-13.6%, respectively, and clipping yield by 44.4-45.8% and 40.6-40.9%. When evaluated with the growth of shoot length after applying PGRs, residual days of TE and PC were 43.6 and 37.9 days after treatment of PGRs (DAT) in the 1st experiment (July 29-August 26), respectively, and 38.3 and 39.5 DATs in the 2nd experiment (September 30-October 28). These results indicated that an application of TE or PC decreased shoot length and clipping yield in the perennial ryegrass, and their residual time was about 40±3 DATs. Perennial ryegrass applied with PGRs like TE and PC was not significant seasonal difference, and might be not phytotoxic.

• Journal of Sericultural and Entomological Science
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• v.25 no.2
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• pp.32-36
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• 1984

This study was conducted out to evaluate the efficacy of insecticides, furadan (3%G), disyston(5%G), ortran (50%WP), pirimor (50%EC) and metasystox (25%EC) to the mulberry thrips(Pseudodendrothrips mori NIWA.) The comparisons between damaged by thrips and controlled leaves with the cocoon producion and the chemical contents in leaves were carried. The results were as follows; 1. Ortran, furadan and matasystox showed the good efficacy to control the thrips, especially the period of efficacy was the longest in ortran and furadan. 2. The cocoon yield increased in the controlled plot by 3.68kg/box and 5.15kg/10a more than in the damaged plot in autumn rearing season. 3. The content of total carbohydrate and water in mulberry leaves was clearly higher in the controlled plot than in the damaged plot. This may cause the earlier leave harding by damage in autumn.

• Korean journal of applied entomology
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• v.38 no.1
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• pp.47-52
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• 1999

Effects of organic matter content in soil on activity. vertical migration. and persistence of two nernaticides. carbofuran and ethoprophos. to root-knot nematode, Mrloitlog!~iei ~lcognita.w ere investigated. As the organic matter content increased. activity of the nernaticides tended to be reduced. Both nematicides exhibited control values of more than 80'k' to M. iix.o,yilit~iln 0-2 cm depth soil layer from the surface. regi~rdless of organic matter content in soil. In 2-4 cm depth soil layer. however. the control value of the neniaticides varied with the organic niatter content in soil. The control value of carbofuran in the soil layer was ranged from I0 to 30'2,. depending on the soil organic niatter content. In contrast. ethoprophos had no control value against M. i/ic.o,ytlitcr in the \oil layer, except that the nematicide had a control value of 30% when the organic matter content was 0.4%. Furthermore. ethoprophos had no effect on controlling M. i/ic.o,gtiitrr in soil layer of below 4cm. whereas control values of carbofuran were approximately from 5 to 20% in all test soils having different organic matter contents. These results indicate that carbofuran has more vertical migration effect than ethoprophos. Persistence of the two neniaticides was also decreased with increasing soil organic matter content. Half life of carbofuran was 2-3 weeks in soil containing 0.4% organic matter, whereas it was found to be I week in soils containning 0.8 ant1 1.6% of organic matter. On the other hand. activity of ethoprophos was reduced to half in 3-3 weeks and in 2-3 weeks in soil containing 0.4 and 0.8%, and 1.6%) of organic matter, respectively. However, no activity of the both nernaticides was found in soil containing 3.2% of organic matter.