• Korean journal of applied entomology
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• v.47 no.4
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• pp.429-433
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• 2008

On the leaf disc of fruit vegetables (cucumber, sweet pepper, tomato, egg plant, oriental melon), it has been evaluated that the capability of four predatory mites (Amblyseius swirskii Athias-Henriot, Neoseiulus barkeri (Hughes), N. cucumeris (Oudemans), N. californicus (McGregor)) to prey on the eggs of Bemisia tabaci (Gennadius) and to lay own eggs. The most aggressive mite was A. swirskii which had consumed about $9{\sim}12$ eggs in a day. The quantity of eggs consumed by N. barkeri, N. cucumeris and N. californicus was about $6{\sim}9,\;4{\sim}6$ and $1{\sim}4$, respectively. The most productive mite was also A. swirskii which had laid about $1.2{\sim}1.9$ eggs in a day. The others could not lay more than 0.5 eggs in a day.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.355-359
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• 2009

By releasing predatory mite, Amblyseius swirskii Athias-Henriot, with 25 individuals per cucumber plant in a commercial greenhouse (1,600 $m^2$), the population of western flower thrips, Frankliniella occidentalis (Pergande), was kept under the economic threshold level. The initial thrips population of 18.3 individuals per leaf decreased to 2.1 individuals per leaf after four weeks, while the number of A. swirskii reached to 16.6 individuals per leaf. It was also observed that at a point where the thrips occurred in high density of about 34.3 individuals per leaf, A. swirskii population built up on the lower part of cucumber plant first, but as time passed the predatory mites moved upward to the top of the plant and aggregated.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.385-391
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• 2010

This study reports the results of natural enemy application against four insect pests on greenhouse sweet pepper in winter cropping system. Orius laevigatus ($3.3/m^2$) was released at two different times (Nov. 2005 & Feb. 2006) to control Frankliniella occidentalis, western flower thrips (WFT). Throughout the cropping season, the lowest level recorded of WFT was less than 2.0 individuals per yellow sticky trap. Amblyseius swirskii ($232.3/m^2$) was released four times (Nov. 2007 ~ Aug. 2008) to control Bemisia tabaci, tobacco whitefly (TWF). Until July 2008, TWF population had been suppressed lower than 6.6/trap. Phytoseiulus persimilis ($44.5/m^2$) was released seven times (Apr. 2008 ~ Aug. 2008) to control Tetranychus kanzawai, tea red spider mite (TRSM). As a result, TRSM population was suppressed lower than 1.7/1eaf. To control aphids, Aphidius colemani ($9.5/m^2$) was released seven times (Oct. 2004 ~ Jan. 2005), with the transplantation of banker plants ($5.5pot/660m^2$). As a whole, aphid's population has been successfully reduced to less than 2.0/leaf.

• Korean journal of applied entomology
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• v.51 no.2
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• pp.83-90
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• 2012

The effect of natural enemies on four major pests of hot pepper was tested in greenhouses. The aphids were successfully controlled by introducing three Aphidius colemani-banker plants, and releasing 23.3 wasps per $m^2$ on April 16 and 23 wasps per $m^2$ in a greenhouse of 660 $m^2$. To control thrips, Orius laevigatus was released twice, 3.0 bugs per $m^2$ at a time(May $11^{th}$ and June $12^{th}$). The thrips population was controlled within 0.3 thrips per flower during the growing season. To control two species of mites, Tetranychus kanzawai and Polyphagotarsonemus latus, and the silverleaf whitefly, Bemisia tabaci, a total of 113.7 individuals of Amblyseius swirskii were released twice(May $11^{th}$ and $30^{th}$). The densities of B. tabaci and T. kanzawai were kept within 171.0 individuals/trap and 0.8 individual/leaf, respectively. P. latus was suppressed completely twelve days after release. The cost of the released natural enemies to control the four arthropod pests in this study was 420,000 Won per 660 $m^2$.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.503-508
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• 2009

Biological-control-based-integrated-pest-management of major pests occurring on sweet pepper in greenhouse during summer season was tried. As many as 2.1 Orius laevigatus per $m^2$ were released in two times on June 6 and 19, and the population of thrips was kept under control and accordingly the damage was negligible throughout the season. To control aphids, a total of 0.8 Aphidius colemani per $m^2$ were released in four times, 0.2 of them at a time, flonicamid on May 14 and July 18 and pymetrozine on June 14 and September 4 were sprayed on the spots of high aphid occurrence to reduce the release of the wasp, and the density of aphids was kept under control. Whitefly was controlled successfully by releasing a total of 343.4 Amblyseius swirski per $m^2$ in nine times, 38.1 of them at a time, from May 9 until November 12 and dinotefuran was sprayed on November 12 when the density of whitefly increased up to 200 per trap. Tetranichus kanzawai was controlled by both Phytoseiulus persimilis which was released a total of 44.4 per $m^2$ in five times 8.9 of them at a time from May 23 to September 10, and the A. swirski which was released for the control of whitefly.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.47-58
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• 2012

Effect of a new crop protectant 'Bt-Plus' on natural enemies was analyzed in this study. Tested natural enemies included two parasitic species of $Aphidius$ $colemani$ and $Eretmocerus$ $eremicus$, and four predatory species of $Harmonia$ $axyridis$, $Orius$ $laevigatus$, $Amblyseius$ $swirskii$, and $Phytoseiulus$ $persimilis$. 'Bt-Plus' was formulated by combination of three entomopathogenic bacteria ($Xenorhabdus$ $nematophila$ (Xn), $Photorhabdus$ $temperata$ subsp. $temperata$ (Ptt), $Bacillus$ $thuringiensis$ (Bt)) and bacterial metabolite (BM). All three types of 'Bt-Plus' showed significantly higher toxicities against fourth instar $Plutella$ $xylostella$ larvae than Bt single treatment. Two types of bacterial mixtures ('Xn+Bt' and 'Ptt+Bt') showed little toxicity to all natural enemies in both contact and oral feeding assays. However, 'BM+Bt' showed significant toxicities especially to two predatory mites of $A.$ $swirskii$ and $P.$ $persimilis$. The acaricidal effects of different bacterial metabolites were evaluated against two spotted spider mite, $Tetranychus$ $urticae$. All six BM chemicals showed significant acaricidal effects. The BM mixture used to prepare 'Bt-Plus' showed a high acaricidal activity with a median lethal concentration at 218.7 ppm (95% confidence interval: 163.2 - 262.3). These toxic effects of bacterial metabolites were also proved by cytotoxicity test against Sf9 cells. Especially, benzylideneacetone, which was used as a main ingredient of 'BM+Bt', showed high cytotoxicity at its low micromolar concentration.

• Korean Journal of Organic Agriculture
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• v.21 no.1
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• pp.95-104
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• 2013

This research was performed to test the effects of oleic acid for the management of greenhouse whiteflies and tobacco whiteflies. Tobacco whiteflies, especially, are the vectors of tomato yellow leaf curl virus on tomato plants. Whiteflies are not only the vectors of various viruses but also the major insect pests that cause direct damages through sucking and induce sooty mold with their sweet dew on tomato plants. There are many eco-friendly management measures including the use of yellow sticky trap and natural enemies such as Eretmocerus eremicus and Amblyseius swirskii. However, these management measures have difficulties to implement in the greenhouse. Therefore, in this research, oleic acid was tested for its effect on the management of whiteflies at various concentrations of 1,000ppm, 2,000ppm, or 4,000ppm. As a result, treatments of 1,000ppm, 2,000ppm and 4,000ppm oleic acid showed the control value of 70%, 76% and 84%, respectively. In another test, treatments of 2,000ppm oleic acid, and control treatment of 1,5000ppm neem oil and 50ppm dinotefuran showed the control value of 82%, 75%, and 75%, respectively. Cost for one application of oleic acid and neem oil for 10a area would be 3,180 Won and 20,150 Won, respectively. As a result, it was assumed that the use of oleic acid would be a appropriate management measure.