• The Korean Journal of Pesticide Science
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• v.8 no.1
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• pp.16-21
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• 2004

A series of experiments was conducted to determine the toxicities of thiodicarb on the six lepidopterous pests (Pseudaletia separata, Plutella xylostella, Palpita indica, Spodoptera exigua, Helicoverpa assulta, Spodoptera litura) and to elucidate factors insecticidal effects mechanism of thiodicarb. Thiodicarb was very effective against six lepidopterous young larvae, but less effective to the old larvae and it acted slowly. Thiodicarb inhibited acetylcholinesterase and glutathione S-transferase activities, but not inhibit esterase activity.

• Korean journal of applied entomology
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• v.54 no.2
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• pp.55-62
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• 2015

'Bt-Plus' has been developed by mixing spores of Bacillus thuringiensis (Bt) and culture broth of Xenorhabdus nematophila (Xn). Despite its high toxicity, it has some imitation to broaden its efficacy against diverse insect pest spectrum. This study focuses on enhancement of Bt-Plus toxicity against semi-susceptible insect, Spodoptera exitgua, by addition of Xn metabolites. Two main Xn metabolites, oxindole (OI) and benzylideneacetone (BZA), are known to enhance the Bt insecticidal activities. The addition of OI or BZA significantly increased Bt-Plus pathogenicity. However, when the freeze-dried Xn culture broth was added to Bt-Plus, much less amount was enough to enhance the toxicity compared to the amount of OI or BZA. An HPLC analysis indicated that there were more than 12 unidentifed bacterial metabolites in Xn culture broth. These suggest that there are potent biological response modifiers in Xn metabolites other than OI and BZA.

• Korean journal of applied entomology
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• v.32 no.1
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• pp.24-29
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• 1993

Experiments were conducted to study effects of different bioassay methods on toxicity to the German cockroach (Blattella germanica L.) ith six insecticides. For male adults, by dry film method, the {TEX}$LC_{50}${/TEX} value of chlorpyrifos. fenvalerate, propoxur, permethin, DDVP, and hydramethylnon was 1.79, 1.87, 3.04, 4.37, 32.72, and 270.81 ppm, respectively and the same tendency was shown in the female. For male adults, by topical micro-application method, the {TEX}$LD_{50}${/TEX} value of DDVP and fenvalerate, chlorpyrifls, permethrin, propoxur, hydramethylnon was 2.63, 3.79, 4.51, 6.73, 44.99 $\mu\textrm{g}$/g, respectively and the same tendency was shown in the female. From the diet toxicity method against male adults, the CT value (Concentration%$\times${TEX}$LT_{50}${/TEX}) showed that chlorpyrifos was rapid effective and hydramethylnon was residual effective.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.43-49
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• 2006

Larvicidal activity of 34 plant essential oils were tested against the 4th instar larvae of Culex pipiens pallens. Among them, six oils (basil, fennel, caraway seed, lime, thyme red, and thyme white) showed more than 80% mortality at 100 mg $litre^{-1}$ concentration. GC and GC-MS analyses of the six essential oils and bioassay of their components revealed that anethole (a major component of fennel and basil oil) and (+)-limonene (a major component of caraway seed and lime oil) showed higher larvicidal activities than others. In addition to the above two components, ${\alpha}$-phellandrene, p-cymene, $\gamma$-terpinene, ${\beta}$-pinene, and thymol showed higher larvicidal activity than Bt product.

• The Korean Journal of Pesticide Science
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• v.20 no.2
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• pp.159-164
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• 2016

The winter cherry bug (Acanthocoris sordidus Thunberg, Coreidae, Hemiptera) is a insect pest that have a piercing sucking type mouthpart, and it is injured to solanaceous plants including pepper plant. For the control of the winter cherry bug, 20 organic synthetic insecticides and 7 environmental friendly agricultural materials (EFAMs) were selected with single formulation. Fenitrothion, fenthion and phenthoate were significantly higher mortality to adults and 3rd instar nymphs of winter cherry bug as over 95 and 100 % after 72 hours with treatment. Otherwise, in case of EFAMs, there is no significantly higher effective materials to adults and 3rd instar nymphs of winter cherry bug. Eighty percentage of Sophora flavescens was showed only around 50% mortality with the high variation after 72 hours with treatment against adult of the winter cherry bug.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.27-33
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• 2000

N-Dimethoxyphosphinothionyl carbofuran, PSC, has a high insecticidal activity and low mammalian toxicity. Ten N-phosphinothionyl carbofuran derivatives were synthesized and their insecticidal activities were determined against brown plant hopper (Nilaparvata lugens), green peach aphid (Myzus persicae), diamondback moth (Plutella xylostella), and two-spotted spider mite (Tetranychus urticae). Green peach aphid, diamondback mea and brown plant hopper were controlled over 90% by application of 125 ppm, 125 ppm, and 63 ppm, respectively, of carbosulfan. Two hundred and fifty ppm of newly synthesized compounds could control most of brown plant hopper and diamondback moth. Especially, insecticidal activities of compound 10 against brown plant hopper, diamondback moth, and green peach aphid were similar to those of carbosulfan. Our results show that the newly synthesized derivatives of NV-phosphinothionyl carbofuran have a similar insecticidal activity to carbosulfan.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.419-427
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• 2013

The insecticidal activity of 124 plant essential oils and control efficacy of six experimental spray formulations (SF) containing 0.25, 0.5, 1, 2.5, 5, and 10% of the selected oils was examined against both nymph and adult of the citrus flatid planthopper, Metcalfa pruinosa using direct contact applications (leaf dipping and spray). Reponses varied according to dose (1,000 and 500 mg/L). When exposed at 1,000 mg/L for 24 h using leaf dipping assay, 19 essential oils showed strong mortality (100%) among 124 essential oils screened. At 500 mg/L, 100% mortality was observed in cinnamon technical, cinnamon green leaf, cinnamon #500, cassia tree, citronella java and pennyroyal followed by origanum, thyme white, grapefruit, savory, fennel sweet, aniseed and cinnamon bark showed considerable mortality (93.3-80%) against nymphs of M. pruinosa. The moderate mortality (73.3-60%) was found in thyme red, tagetes, calamus, lemoneucalptus and geranium. Oils applied as SF-10% sprays provided 100 % mortality against adult M. pruinosa. One hundred mortalities were achieved in cinnamon technical at >SF-0.5 formulation, in cinnamon #500, cinnamon green leaf and penny royal at >SF-2.5. To reduce the level of highly toxic synthetic insecticides in the agricultural environment, the active essential oils as potential larvicides could be provided as an alternative to control M. pruinosa populations.

• The Korean Journal of Pesticide Science
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• v.5 no.1
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• pp.46-54
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• 2001

These studies were carried out to investigate the toxicities of 33 registered insecticide to the American serpentine leafminer, Liriomyza trifolii. Insecticidal activities were evaluated by testing systemic action and residual effect in the laboratory, and control efficacy and phytotoxicity in the greenhouse. All insecticides used in this study did not effect on the egg of L. trifolii, although spinosad showed 70% of egg-hatch suppression. For L. trifolii larvae ($2{\sim}3$ instar), the insecticides with over 95% of insecticidal activity were abamectin, cartap, cyromazine, emamectin benzoate, diflubenzuron + chlorpyrifos. The Insecticide what showed over 90% of insecticidal activity or neonate larvae were abamectin, cartap, emamectin benzoate, diflubenzuron + chlorpyrifos and milbemectin. Only cartap + buprofezin showed over 95% insecticidal activity against L. trifolii pupae. Almost insecticides used in this study little or not effected on the adult of L. trifolii. Emamectin benzoate and milbemectin showed moderate foliar systemic effects on eggs of L. trifolii (53.3, 47.9%, respectively). However, other insecticides showed little systemic effect. For larvae and adults, all insecticides showed low systemic effects. Insecticides with over 90% residual effect for 10 days were abamectin, emamectin benzoate and milbemectin (91.4, 90.4, 91.9%, respectively). In the control efficacy test on L. trifolii 90% of control values were obtained at 14th day after treatment of the insecticides including abamectin, cyromazine, emamectin benzoate and milbemectin. Cartap and cartap + buprofezin showed slight phytotoxicity on kidney bean leaf, however, other insecticides showed no phytotoxic effects. These results indicate that abamectin, emamectin benzoate and milbemectin can be used for tile control of L. trifolii in field.

• Applied Biological Chemistry
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• v.45 no.1
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• pp.37-41
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• 2002

Seven organophosphorus compounds and three carbamates of some monoterpenoids were synthesized and tested for insecticidal activity to five insects, brown plant happer (BPH, Nilaparvata lugens), green peach aphid (GPA, Myzus persicae), diamond bark moth (DBM, Plutella xylostella), tobacco cut worm (TCW, Spodoptera litura), and two spotted spider mite (TSSM, Tetranychus urticae). With the administration of 500 mg/l concentration thiophosphates of carveol and geraniol showed motality of from 95% to 100% to BPH and DBM. On the other hand, phosphates of menthol, thymol, and borneol had also good to moderate activity to BPH and TSSM insects at the same concentration.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.87-96
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• 2011

To study solar activated insecticide, three types of dihydroxyl phosphorus(V) triazatetrabenzocorrole derivatives ($P(OH)_2TBCs$) including H, 4'-methoxy phenoxy, 4'-tert butyl phenoxy substituents were synthesized. The results show that slightly red-shift with introducing substituents was observed and singlet oxygen was generated by the sunlight. Based on photochemical properties, solar activated insecticidal activity tests against Liriomyza trifolii (Burgess) were carried out. Overall insecticidal activities were 100~85.7% in the concentration of 500ppm, and especially in the case of compound $P(OH)_2TBC$ the insecticidal activities was 100%.