• 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.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.125-133
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• 2015

Entomopathogenic fungi have been studied to develop for biological control agents as an alternative to chemical control agents in insect pest management. Two Lepidopteran insects, Spodoptera exigua and Plutella xylostella, are serious insect pests infested various crops, but not effectively controlled by commercial chemical pesticides due to its high insecticide resistance. A fungal isolate was isolated from S. exigua larvae collected from green onion field in Andong, Korea. To identify the fungal isolate, 18srRNA sequence for internal transcribed spacer (ITS) and ${\beta}$-tubulin regions were sequenced. The ITS and ${\beta}$-tubulin sequence were highly matched to Beauveria bassiana and morphological characteristics also was fit to known B. bassiana. Finally, isolated fungus has identified as B. bassiana and named B. bassiana ANU1. The result of bioassay, median lethal concentrations were $2.7{\times}10^3$ and $0.9{\times}10^3conidia/ml$ and medial lethal times were 65.6 and 60.8 h to S. exigua and P. xylostella, respectively. B. bassiana ANU1 showed high pathogenicity to two insect pests from $20^{\circ}C$ to $30^{\circ}C$ at 50% relative humidity (RH) and more than 40% RH at $25^{\circ}C$ with $10^7conidia/ml$ of concentration.

• Korean Journal of Agricultural Science
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• v.35 no.2
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• pp.127-136
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• 2008

Beauveria bassiana can be used as a biological insecticide to control a number of pests. It has been known as that B. bassiana TBI-1 have a insecticidal effect on the twospotted spider mite (Teranychus urticae) and the greenhouse whitefly (Trialeurodes vaporariorum) these days. The biological pest control agent, B. bassiana, showed somewhat insecticidal activities against the cotton aphid, Aphis gossypii, too. After treatment with biological insecticide, the mean of increasing rate of aphids was at around recorded at around 0.21 while at around 0.24 in non-treated TBI-1 biological insecticide condition during 1 week. Consequently, it was found that treatment of Beauveria bassiana reduced an increasing rate of aphid population. Also, we could visually observe dead aphids changed as a reddish mold due to this insecticidal fungus. B. bassiana TBI-1 can significantly reduce an increasing rate of aphid population, so effective biological control against the cotton aphid are possible.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.59-71
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• 2000

The Asian ladybird, Harmonia axyridis, might be distinguished in biological control agents for the several aphid species in the greenhouses as well as in the fields. Therefore, feeding behavior and predacious capability characteristics were observed. When ladybirds are searching for aphids as their preys, they use the maxillary palpus as contact reception. Otherwise, most of aphids escape from walking or chewing ladybird to other place (mainly move to near-by leaf, or fall down to the under-leaf or ground) instead of plant sucking. Consumed time of ladybirds for searching and feeding prey were significantly different and dependent on their development stage. The ladybird adults ate about 120 green peach aphids and 257 cotton aphids per day. The 3rd instar of ladybirds ate 2,420 and 2,750 eggs of greenhouse whitefly on the cucumber and tomato leaf, respectively, as well. However, ladybird instars taken greenhouse whitefly eggs could not continuously develope to adult, on the other hand, ladybirds taken aphids were normal condition.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.197-210
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• 2022

Entomopathogenic fungi can be used to control a variety of sucking and chewing insects, with little effect on beneficial insects and natural enemies. Approximately 170 entomopathogenic fungal insecticides have been registered and used worldwide, with the recent focus being on the mode of action and mechanism of insect-fungal interactions. During the initial period of research and development, the industrialization of entomopathogenic fungi focused on the selection of strains with high virulence. However, improvement in productivity, including securing resistance to environmental stressors, is a major issue that needs to be solved. Although conidia are the primary application propagules, efforts are being made to overcome the limitations of blastospores to improve the economic feasibility of the production procedure. Fungal transformation is also being conducted to enhance insecticidal activity, and molecular biology is being used to investigate functions of various genes. In the fungi-based pest management market, global companies are setting up cooperative platforms with specialized biological companies in the form of M&As or partnerships with the aim of implementing a tank-mix strategy by combining chemical pesticides and entomopathogenic fungi. In this regard, understanding insect ecology in the field helps in providing more effective fungal applications in pest management, which can be used complementary to chemicals. In the future, when fungal applications are combined with digital farming technology, above-ground applications to control leaf-dwelling pests will be more effective. Therefore, for practical industrialization, it is necessary to secure clear research data on intellectual property rights.

• Journal of the korean veterinary medical association
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• v.38 no.4
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• pp.305-316
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• 2002

동물용의약품은 가축질병의 예방 및 치료의 목적으로 이용되어 그동안 우리나라 가축의 질병방제와 사료효율의 증진으로 양축농가의 소득증대와 아울러 축산이 대규모로 발전할 수 있게 하는데 기여한 바가 크다. 그러나 특히 항생제나 합성 항균제의 오남용에 따른 가축의 장내 세균과 병원성 세균의 항생항균제에 대한 내성획득으로 질병치료 효과의 저하, 축산식품을 통하여 이들 제제의 잔류물질이 인체내로 들어가 부작용을 일으키거나 세균의 내성인자가 사람 병원체에 전달되어 사람의 질병치료에 장애요인이 될 수 있는 문제점이 제기되고 있다. 그리고 공중위생전인 측면에서 항생항균제, 호르몬제, 생물학적제제(백신 등), 마취제, 마약류, 등의 요주의동물용의약품을 체계적으로 관리할 필요성이 제기되고 있다. 본 주제에서는 동물용의약품 중 현재 가장 많은 량이 이용되고 있는 항생제를 중심으로 사용실태와 오남용 사례를 살펴보고자 한다.

• Korean Journal of Environmental Biology
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• v.41 no.3
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• pp.273-282
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• 2023

Hypochaeris radicata, native to Europe and Eurasia, is a perennial plant of the Asteraceae family. In Korea, H. radicata was reported in 1992, mainly in Jeju Island, and gradually spreading to the inland. It overwinters in the form of a rosette and blooms yellow flowers from May to June. H. radicata propagates by seeds and rhizomes. The germination temperature of the seed is 15/20℃ (day/night), and the rhizome forms a new plant at a depth of 2-3cm in the soil. The roots of H. radicata secrete allelochemicals that inhibit the development of other plants. Some use it as a salad or forage substitute but to a limited extent. However, extensive research on ampicillin contained in H. radicata has been conducted, and its anticancer and anti-inflammatory effects have been recognized. There are only a few methods to manage H. radicata both culturally and physically. In orchards, soil treatments such as oxyfluorfen and diclobenil, or nonselective foliar treatments such as glufosinate-ammonium and glyphosate are used. Notably, there are no known biological control agents.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.465-469
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• 2016

An entomopathogenic fungus was isolated from the two-spotted spider mite (Tetranychus urticae) in a rearing house, and identified as Neozygites floridana (Entomophthorales: Neozygitaceae). A high infection rate induced by N. floridana could increase the price of the natural enemy. The body color of mites infected by this fungus changed to red or orange and swelling occurred. Fungal conidia were discharged into the webbing produced by the spider mites, making it relatively easy to infect the mites. Primary conidia were pear shaped and capilliconidia almond shaped. The fungus could not be cultured on solid media (PDA, SDAY, or EYSDA), but could possibly be cultured in liquid media (Grace's insect tissue culture medium + 5% fetal bovine serum). Kidney beans were supplied as food for T. urticae; the mite infection rate in a kidney bean canopy was about 36.1%. The density of infected mites was higher on the underside than on the upper side of leaves. Based on the results of this survey, we need to identify methods of fungal control for natural enemy production and biological control agents for T. urticae for effective crop management.

• Korean journal of applied entomology
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• v.49 no.4
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• pp.277-287
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• 2010

Several species of the genus Aphidius are used in biological control programs against aphid pests throughout the world and their behavior and physiology are well studied. While the importance of sensory organs in their behavior is understood, their antennal structure remains largely unknown. In this study, the external morphology and distribution of the antennal sensilla on the antennal of both female and male adults of A. colemani were described using scanning electron microscopy (SEM). Generally, the filiform antennae of males ($l,515.2{\pm}116.5\;{\mu}m$) are longer than females ($l,275.1{\pm}103.4\;{\mu}m$). Antennae of this species are made up of radicle, scape, pedicel and flagellomeres. Male and female antennae differed in the total number of flagellomeres as 15 in males and 13 in females. The result of SEM observation was characterization and grouping of seven types of receptors into morphological classcs: Bohm bristles, Sensilla placodea, 2 types of S. coeloconica and S. trichodea, and S. basiconica as with a tip pore and with wall pores. In addition, the possible functions of the above sensilla types arc discussed in light of previously published literature; mechanoreception (Bohm bristles, S, coeloconica I & II and S. trichodea) and chemoreception (S. placodea, S. basiconica type I & II).

• Korean journal of applied entomology
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• v.15 no.1 s.26
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• pp.7-16
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• 1976

In order to increase utility efficiency of red wood ants, Formica rufa truncicola var. yessonesis Forel as a resource of natural enemy of pine caterpillar, Dendrolimus spectabilis Butler, by finding out ecological and environmental factors in the habitat of red wood ants, the nest distribution and its density in habitat, plant distribution and density, stand-density of red pine, nest building and fixing plants, relative humidity of surface soil, physical and chemical natures of soil, and breeding rate were examined. The obtained results are summarized as follows: 1. The nest of red wood ants was densely distributed, in the lower-and middle top of mountain but no nest was found in the top. 2. The economical distribution of nest of habitat was estimated as $2.85/m^2$ and the lowest density as $1.93/m^2$ and these estimation lead us to confirm that pine caterpillar could be controlled. 3. The ecological characteristics of habitat seemed to be represented as higher stand-density of red pine of 10-20 years of age with large areas of eroded land under trees. The major grasses prevailing in this area were Andropogon brevifolius. Arundinella hirta, Miscanthus purpurasens, Eulia speciosa, Themeda japonica, Cymbopogon goeringii, and Eccoilpus cotulifer 4. Red wood ants seemed to build the nest by using red pine, Arundinella hirta, Miscanthus purpurascens, Themeda japonica or Cymbopogon goeringii as a fixing plant. 5. The limited point of humidity percent in habitat of red wood ants was estimated as $76\%$ during the acting period of May to September and as $72\%$ during pre-period of hibernation of October to November. 6. Soil analysis in habitating region showed higher concentration of organic matters and lower concentration of calcium and magnesium, and habitat was largely composed of silt and fine sand rather than coarse sand. 7. When the separated colony was transplanted to non-habitating red pine forest that seemed to have the similiar conditions as those of habitat, propagation and establishment of nest was possible.