• Korean journal of applied entomology
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• v.43 no.1
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• pp.61-70
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• 2004

Environmentally sound control of Japanese lawngrass cutworm, Spodoptera depravata with Korean entomopathogenic nematodes (Heterorhabditis sp. Gyeongsan, Steinernema carpocapsae GSNI , S. glaseri Dongrae, S. longicaudum Nonsan, and S. monticolum Jiri) was evaluated in the laboratory and field. In addition, effect of turf height on the pathogenicity of entomopathogenic nematodes and density of ant (Formica japonica) and spine-tailed earwigs (Forficula scudderi) were investigated in the field. The corrected mortality of 3rd instar of S. depravata larvae was 53.3% to 66.7% 5 days later after treatment of entomopathogenic nematodes. $LC_{50}$ value of S. carpocapsae GSN1 and S. monticolum Jiri against 3rd instar of S. depravata was 6.9 and 3.9, respectively. Pathogenicity of S. carpocapsae GSN1 was different depending on larval stages, i.e., mortality of 2nd instar was the highest representing 73.3% but decreased from 3rd instar. Turf height affected pathogenicity of entomopathogenic nematodes. Mortality of 4th instar of S. depravata was 40.0% by S. carpocapsae GSN1 and 33.3% by S. monticolum Jiri, and 83.3% by fenitrothion, respectively, in the turf height of 14mm, but those were lower in 45mm. The corrected mortality of S. depravata larvae was lower at the entomopathgenic nematode plots than fenitrothion plot in the distribution field of Formica japonica. However, reduction rate of F japonica was higher in fenitrothion by 56.7% compared with 0% in S. carpocapsae GSN1 and 6.7% in S. monticolum Jiri. Turf height influenced control of S. depravate in S. carpocapsae GSN1 and fenitrothion. Control value of S. carpocapsae GSN1 was 62.2% in the turf height of 3-4cm, but not effective at all in 6-8cm and 12-14cm. However, there was not significantly different in fenitrothion plots. Forficula Scudderi was also reduced only in fenitrothion plots. Reduction rate was 100% in 3-4cm, 41.7% in 6-8cm, and 16.7% in 12-14cm, respectively.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.51-58
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• 2000

These studies were carried out to investigate the toxicities of 43 registered insecticides to the sweetpotato whitefly(Bemisia tabaci, B. biotype). Insecticide activities were evaluated by testing systemic action and residual effect in the laboratory, and control efficacy in the greenhouse. All experiments were tested at the recommended concentration(ppm) of each insecticides. Insect growth regulators (IGRs), pyriproxyfen and teflubenzuron showed >95% ovicidal effect. The insecticides that showed >95% larvicidal activity on 3rd nymphal instars were abamectin, acetamiprid, imidacloprid, pyriproxyfen, and acetamiprid+ ethofenprox. Insecticides with >95% adulticidal activity were abamectin, acetamiprid, diazinon, endosulfan, fenitrothion, imidacloprid, methidathion, pirimiphos-methyl, pymetrozine, spinosad, acetamiprid+ ethofenprox, cartap kydrochloride+buprofezin, and fenpropathrin+fenitrothion. Abamectin, acetamiprid, imidacloprid, pyriproxyfen, and acetamiprid+ethofenprox showed both residual effect and systemic activity. In the control efficacy test on B. tabaci, 90% control values were obtained at 1st day after treatment of the insecticides including abamectin, acetamiprid, imidacloprid, pyriproxyfen and acetamiprid+ethofenprox but in pyriproxyfen, 90% control value was reached at 7th day after treatment. These results indicate that abamectin, acetamiprid, imidacloprid, pyriproxyfen and acetamiprid+ethofenprox can be used in control for B. tabaci in field.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.571-576
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• 1998

Experiments were conducted to evaluate the efficacy of the application of low concentration insecticides by sprinkler system for control of the pine needle gall midge, Thecodiplasis japonensis, by killing the adults emerging and copulating near the ground. For ground spray, 2 insecticides of fenitrothion and deltamethrin, dilutions of $2,000{\times}$ and $3,000{\times}$ deltamethrin, and 3 spray intervals of 1-3 day were tested at the peak time of adult emergence during the day time. The results are as follows ; 1. Ground spray of fenitrothion 50% EC and deltamethrin 1% EC were found to be highly effective for control of the pine needle gall midge. Average gall formation by fenitrothion, deltamethrin and untreated ones were 3.40%, 5.23% and 45.69%, respectively ; control value of both insecticides exceeded 88%. 2. As a ground spray of deltamethrin 1% EC, dilution $2,000{\times}$ was significantly different from $3,000{\times}$ in gall formation rates. Average gall formation of $2,000{\times}$ plots and $3,000{\times}$ treated ones were 5.23% and 18.00% ; control values were 89.44% and 63.66%, respectively. 3. Diurnal treatment of ground spray was found to be highly effective for control of pine needle gall midge. 4. In particular, control by ground application of dilutions $2,000{\times}$ and $3,000{\times}$ of deltamethrin is suggested because it does not have an adverse effect on arthropods of the ground surface such as ants and spiders.