• Korean journal of applied entomology
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• v.40 no.3
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• pp.253-258
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• 2001

Biological control of thrips with Orius strigicollis Poppius was evaluated in a hot pepper greenhouse. To study the biological control strategy of thrips on hot pepper grown in greenhouse, three plots were established: natural enemy removed plot(CNT), pesticide treated plot(PAT) and O. strigicollis released plot with no pesticide application (NRT). The nymphs of O. strigicollis were found on the leaves of lower stratum in CNT and NRT at 13 days after the first release. The density of thrips was suddenly dropped and maintained at low level since 15 day after transplanting in NRT. The densities of thrips on hot pepper flowers was also maintained at much less level in NRT than in CNT. The thrips and O. strigicollis, which were aggregated in flowers, may have resulted in improved predator searching. Average damage indices of CNT, PAT and NRT were 0.31, 0.05 and 0.08 and the percentage of damaged fruit were 80.0, 17.1 and 24.8% respectively. The damage index and percentage of damaged fruit of NRT was slightly higher than PAT, but very lower than CNT. The introduction of the adults of O. strigicollis, which was the biological control agent for the control of thrips, was effective on hot pepper.

• Korean Journal of Weed Science
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• v.31 no.1
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• pp.103-111
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• 2011

Monochoria vaginalis var. plantaginea (Pontederiaceae) is one of the most problematic weed in the rice field in Korea. Tanysphyrus (Tanysphyroides) major was selected as a potential biological control agent for M. vaginalis. Continuous rearing of T. (T.) major was carried out from 2006 to 2007, and its morphological characteristics and ecological characteristics were investigated. This species has a single generation per year, over-wintering as an adult stage. The emergence of adults starts in later June and last until September. These observations indicate that T. (T.) major takes $22{\pm}0.7$ days to develop from egg to adulthood. Host specificity test showed that finally selected this species was suitable candidates for the biological control of M. vaginalis var. plantaginea since it showed negative host specificity against major 60 test crops.

• Korean Journal of Organic Agriculture
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• v.26 no.1
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• pp.129-140
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• 2018

Pectobacterium carotovorum subsp. carotovorum was found to be highly virulent to various vegetables, including Chinese cabbage. The antibacterial isolate CAB12243-2 was tested in a field bioassay for suppressing soft rot disease. The nucleotide sequencing of the 16S rRNA gene identified, the CAB12243-2 strain used in this study as Bacillus toyonensis. B. toyonensis CAB12243-2 inhibited the pectate lyase process by soft rot pathogens, and used trehalose and glucose as carbon sources. In field tests, the antibacterial isolate B. toyonensis CAB12243-2 suppressed soft rot disease with 73.0% control efficacy on the spring cultivar "Norangbom" and with 68.9% efficacy on the fall cultivar "Bulam 3". These results suggest that B. toyonensis CAB12243-2 can be used as a biological control agent for the control of soft rot diseases on vegetables.

• The Korean Journal of Soil Zoology
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• v.8 no.1_2
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• pp.17-22
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• 2003

An endemic entomopathogenic nematode, Heterorhabditis megidis, was evaluated by its control efficacies against housefly, Musca domestica, and flower beetle, Gametis jucunda. In Petri-dish assay, the pathogenicity of H. megidis showed 456.4 infective juveniles/larva (IJs/larva) in median lethality (LC$_{50}$) against the second instar larvae of M. domestica and 238.9 IJs/larva against the second instar larvae of G. jucunda. This was contrasted with those of the other well-known entomopathogenic nematode, Steinernema carpocapsae, which showed 115.9 IJs/larva against M. domestica and 388.6 IJs/larva against G. jucunda. In field experiment, H. megidis were applied per square meter of pork farm with 1,000,000 IJs of H. megidis or apple orchard with 370,000 IJs, which were infested with M. domestica or G. jucunda, respectively. H. megidis showed 56.9% and 57.3% of control efficacies against M. domestica and G. jucunda, respectively. These results suggest a promising control technique in the field using H. megidis against M. domestica and G. jucunda.a.

• Korean journal of applied entomology
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• v.28 no.4
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• pp.229-236
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• 1989

A combined field release of indigenous larvivoroug fish (Aplocheilus latipes) and hybrid herbivore (Tilapia mossambicus miloticus) was conducted to determine the effectiveness of biological control, in particular, against malaria vector (anopheles sinensis), breeding in weedy habitat of rice fields at the University rice paddies at Suwon during the period of June through September in 1988. A combined fish introduction at the release rate of 2.0 fish per $M^{2}$ for Aplocheilus and 1-pair $10M^{2}$ water surface for Tilapia resuited in 70.8% Anopheles larval reducton in a week period, the rates of rontrol increased to 73. 5% and 80.2% in 4th and 5th week respectively after the fish introdurtion, maintaining mosquito suppression in range of 80~82% control after the 5th week against Anopheles and Culex spp. combined. In a single fish treatment with Aplocheilus at 2.0 $fish/M^{2}$ release rate, Anopheles larval reduction ranged on the average 51.4~56.5%in 4 wrek period which was later integratpd with B.t.i. (Rl53.78) treatment at 1.0 kg/ha dosage rate to suppress vector mosquito population down and the the results was compared with that of combined fish introdurtion.

• 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.46 no.1 s.145
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• pp.57-62
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• 2007

Reproductive incompatibility is an Important factor to select a specific biologlcal control agent for successful augmentation of the corresponding endogenous population. An endoparasitoid, Cotesia plutellae (Kurdjumov), is an effective control agent to diamondback moth, Plutella xylostella (L.) and has been known to be classified into two groups in terms of reproductive incompatibility. This study analyzed an Korean population of C. plutellae in terms of morphological characters and mitochondrial DNA marker, which did not match with either of two reproductive incompatibility groups. These results suggest that a Korean population of C. plutellae can be involved in a novel reproductive group. For any augmentation program of C. plutellae in Korea, reproductive incompatibility should be seriously considered to select a particular exotic population.

• Korean journal of applied entomology
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• v.43 no.3 s.136
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• pp.233-239
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• 2004

The potential of five entomopathogenic nematodes, Steinernema carpocapsae Pocheon strain, S. logicaudum Nonsan strain, S. glaseri Dongrae strain, Heterorhabditis bacteriophora Hamnyang strain, and Heterorabditis sp. Gyeongsan strain were evaluated as biological control agents against a mushroom fly, Mycophila speyeri in the mushroom, Pleurotus ostreatus cultivation house. Control effect of M. speyeri was significantly different according to nematode species. Heterorhabditis was more effective than Steinernema. H. bacteriophora Hamnyang strain showed the highest control effect representing $49.0\%$ (7 days), $89.5\%$ (14 days) and $89.1\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $46.5\%$ (7 days), $76.6\%$ (14 days) and $85.4\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$ in Changnyoung, Gyeongnam, respectively. In Jinju, Gyeongnam, control effects of the sa me species were $54.0\%$ (7 days), $74.5\%$ (14 days), and $79.8\%$ (21 days post-treatment) at the rate of $1\times10^6$ and $49.0\%$ (7 days), $76.6\%$ (14 days), and $61.1\%$ (21 days post-treatment) at the rate of $1.0\times10^5$ Ijs/$1.5 m^2$, respectively.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.18-26
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• 2001

Application of the Asian ladybird (Harmonia axyridis) to control several species of aphids in the plastic green houses in mind, control effects of aphid populations regulated by the Asian ladybird were observed. The green peach aphid, the turnip aphid, and the cotton aphid were present on mustard plants, Angelia utlis, ornamental kales, and egg plants at greenhouses in spring, summer, and winter. Adults and larvae of the Asian ladybird used in experiments were collected from aggregated sites at Taejon in the autumn and reared on the cotton aphid in the laboratory. In winter, more number of adults and larvae of ladybirds than in other seasons were needed to control aphid population in successively double plastic greenhouses with supplied subterranean water for keeping warmth. In spring and summer, it was possible to keep the aphid populations low when necessary by manipulating ladybird populations according to the density of aphids. On the other hand, the innate increasing rate of aphid, the aphid population density at the time of applying ladybird, the predacious ability of ladybird at specific developmental stages, and needed periods should be taken into account to control aphids. In addition, the environmental factors, for example, optimum temperature and humidity should be considered to be biologically effective when ladybirds are released to greenhouses.

• Journal of the Korean Society for Marine Environment & Energy
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• v.6 no.2
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• pp.3-15
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• 2003

Recently more than 450 incidents of oil spill a year have occurred in nearshore of Korea, which caused unmeasurelable losses in fisheries and severe damage in marine ecosystem. Two approaches remain paramount in any response to marine oil spill : the enhancement of natural dispersion of the oil by using dispersants, and mechanical recovery using booms and skimmers. A technique currently receiving fresh attention is the enhancement of the natural bioremediation of oil through the application of micro-organisms and/or nutrient. Oil, like many natural substances, will biodegrade over a period of time into simple compounds such as carbon dioxide, water and biomass. Bioremediation is the term used to describe a range of processes which can be used to accelerate natural biodegradation. More specifically biostimulation is the application of nutrients, and bioaugremetation or seeding is the addition of microbes specially selected to degrade oil. Bioremediation is an economically attractive method for the clean-up of oil-contaminated area. Bioremediation has been demonstrated to be an effective oil spill countermeasure for use in cobble, sand beach, salt marsh, and mud flat environment.