• Korean journal of applied entomology
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• v.33 no.2
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• pp.88-95
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• 1994

• Korean journal of applied entomology
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• v.33 no.3
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• pp.201-206
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• 1994

Trunk implantation method of phosphamidon 50% Lq.is commonly applied to control the pine needle gall midge (Thecodiplosis laponensts Uchida et Inouye) Since trunk implantaion is normally practiced during the late Spring, it is often difficult to accommodate necessay labor in mral area. As an alternative, aerial spraylng of less toxic ~nsecticide was designed. Usage of less toxic insecticide in the aenal control of pine needle gall midge can reduce the damage to forest ecosystem. The buproferin, one of the insect growth regulator, was selected at d~fferent rate of dilutions and the treatments effects ruere evaluated at different date and time When 50 t~mes diluted solution of buprofezin 40% SC was treated on different period, there was no significant difference in dficacies. the control efficacies of buproferin 40% SC was measured by occurrences (%) of gall formation of the pine needle gall midge using a ultra low volume (ULV) sprayer and the dilutions of 10X 30X and 50X of buprofez~n 40% SC gave efficacies. 72.4. 57.6 and 8.4, respectively.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.81-87
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• 1994

The experiments were canied out to investigate the toxicological characteristics of Insect Growth Regulators (IGRs) such as chlorfluazuron, diflubenzuron, pyriproxyfen and tebufenozide against the various stages of instars of fall webwom (Hyphantrio cuneo Dmy) and nce stem borer (Chiio suppressaiis Walker). In fall webwom, the tolerance ratio m) with the 2nd-6th instars, as cornpared with LCso of the 1st instar, ranged 107-358, 1.13-6.06, 1.02-3.23 and 1.05- 6.64, respectively. In the rice stern borer, the TR of the 3rd instar, as compared with LCso of the 1st instar, to chlorfluazuron, diflubenzuron, pyriproxyfen and tebufenoz~de were 2.86, 260, 19.80 and 15.30, respectively.

• Korean journal of applied entomology
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• v.33 no.4
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• pp.281-285
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• 1994

This study was conducted to establish a nce insect pest control system, ~ es.ys tematic application of insecticides using carbohran and buproiezin, in Korea. The effects oi various dates of application and rates of buprofezin (25% WP) after carbofuran (3G) soil incorpombon in late May on the pop~~lation densities of the brown planthoppa (BPH) immigrating in July were investigated Appropriate application tune of buprofezin for the BPH that had evaded insecticidal effect of 5011 incorporated carbofuran was late July-early August. Application rate of buprofezln at 7.0g a.i/lOa was enough to suppress the BPH density. Buprofezin treatment after carbofumn soil incorporation could also suppress the whlte backed planthopper population but did not affect the densities oi the paddy rice spiders. Considering the charactenstics of occurring patterns of the nce insect pests in Korea. buprofezin treatment m late July or early August after carbofuran soil incorporation in late May can be a useful application system of ir~sectic~deins controlling early season Insect pests and migmtoly planthoppers on rice.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.480-485
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• 1992

Laboratory studies were done to evaluate the effects of diflubenzuron on embryonic and postembryonic development of Riptortus clavatus Thunberg. Diflubenzuron prevented egg hatch; younger eggs(O-12 h old) were 2 times as susceptible as older(48-60 h old) eggs, but embryos of both younger and older eggs developed normally. Susceptibility of nymphs to diflubenzuron decreased with each successive molt. Compared with the first instar, relative tolerance to diflubenzuron was 1.5 times for the second instar, 18.2 times for the third instar, 39. 4 times for the fourth ins tar and 42.4 times for the fifth instar. Even as low concentrations, diflubenzuron prevented significant numbers of third instar nymphs from developing to fourth and fifth instar nymphs or adults. Weight, longevity and fecundity of adults surviving treatment in the final (fifth) instar were also adversely affected.