• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.43-49
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• 2006

Larvicidal activity of 34 plant essential oils were tested against the 4th instar larvae of Culex pipiens pallens. Among them, six oils (basil, fennel, caraway seed, lime, thyme red, and thyme white) showed more than 80% mortality at 100 mg $litre^{-1}$ concentration. GC and GC-MS analyses of the six essential oils and bioassay of their components revealed that anethole (a major component of fennel and basil oil) and (+)-limonene (a major component of caraway seed and lime oil) showed higher larvicidal activities than others. In addition to the above two components, ${\alpha}$-phellandrene, p-cymene, $\gamma$-terpinene, ${\beta}$-pinene, and thymol showed higher larvicidal activity than Bt product.

• The Korean Journal of Zoology
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• v.37 no.2
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• pp.267-273
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• 1994

빨간집모기가 흡혈한 후 체내에서 일어나는 total RNA 변화를 조사한 결과 흠혈 후 6시 간 이후에 RNA양이 증가하기 시작하여 18시간에서 peak를 보인 후 감소하다가 30시간째 부터 증가하기 시작하여 48시간 후에 최대의 RNA 양을 보인 후 급격히 감소하였다 난소에서의 RNA 합성을 정량한 결과 흡혈 후 24시간 이전에는 흡혈 전에 비하여 전혀 증가하지 않았고 30시간 이후부터 증가하기 시작하여 48시간에 가장 많은 양의 RNA가 난소내에 존재하였고, 그 후 급격히 감소하였다. 흡혈 후 6시간 간격으로 난소로 부터 total RNA를 추출하여 in vitro translation을 실시하고 TCA 침전법과 면역침전법으로 합성된 3H-protein과 3H-vitellogenin을 정량하였다. 그 결과 흡혈 후 36시간 이후의 난소로부터 3H-protein과 지-vitellogenin의 합성이 일어나기 시작하여 48시간된 난소에서 가장 많은 양의 3H-protein과 3H-vitellogenin이 합성되었으며, 이때 합성된 단백질의 약 45% 정도가 난황단백질인 3H-vitellogenin으로 나타났다 이상의 결과로 빨간집모기에서는 지방체에서 뿐만 아니라 난소에서도 난황단백질의 합성이 일어남을 알수 있다.

• Journal of environmental and Sanitary engineering
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• v.20 no.3 s.57
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• pp.44-50
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• 2005

Studies on the insecticides susceptibility of adults females Culex pipiens pallens were carried out in 2003. The pupae were emerged originated wild-caught larvae in Ansan city, Korea. The test methods employed, using 7 organophosphorous insecticides, four synthetic pyrethroides, and fipronil penyrazole were evaluated. The following results were obtained 1. Fipronil has showed the most strong value in $LD_{50}\;0.00075{\mu}g/female$, out of 12 kind of insecticides, and followed by deltamethrin 0.0071, $\delta-cyhalothrin\;0.008$, profenofos 0.0082 and $\beta-cyfluthrin$ 0.0088, respectively 2. The killing effect of lambdacyhalothrin and profenophos against adult females Culex pipiens pallens was examined using thermal fogging. The mortality rate were lambdacyhalothrin $41.1\%$ and profenophos $50.7\%$, respectively. The killing effect of thermal fogging was highly effectiveness to distance 6m from nozzle

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.46-50
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• 1999

Methanol extracts of 9 kinds of native medicinal plants(Taraxacum platycarpum, leaf; Pinus densiflora, leaf; Artemisia prinseps, leaf; Allium tuberosum, leaf; Cassia obtussifolia, whole; Sophora angestifolia, root; Stemonae sessilifolia, root; Lonicera japonica stem, leaf, flower; and Clivia miniata) were investigated for insecticidal effect. Methanol extracts of Pinus densiflora leaves and Sophora angestifolia radix showed relatively good insecticidal activity against Culex pipiens pallens larvae. Strong larvicidal activity against the Musca domestica larvae was produced from methanol extracts of Taraxacum platycarpum leaves and Allium tuberosom leaves. while Stemonae radix showed moderate activity. All materials tested revealed little or weak insecticidal activity against M. domestica adults.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.117-123
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• 2006

Fumigant toxicity of 34 plant essential oils were tested against female adults of Culex pipiens pallens. Seven oils (basil, coriander, fennel, pennyroyal, peppermint, thyme red, thyme white) showed more than 60% mortality at 1 ${\mu}L\;L^{-1}$ air concentration and pennyroyal oil appeared to have the highest adulticidal activity. GC and GC-MS analysis of the seven essential oils and bioassay of their components revealed that pulegone (a major component of pennyroyal oil) and anethole (a major component of fennel and basil oil, $LD_{50}$, ${\mu}L\;L^{-1}$ air =0.49) showed higher adulticidal activities than others. In addition to the above two components, linalool ($LT_{50}$, min=0.91), camphor ($LT_{50}$, min=1.06), fenchone ($LT_{50}$, min=1.16), 1,8-cineole ($LT_{50}$, min=2.93), and geranyl acetate ($LT_{50}$, min=1.60) also showed higher adulticidal activity than empenthrin ($LT_{50}$, min=3.45).

• Applied Microscopy
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• v.29 no.2
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• pp.223-230
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• 1999

The epithelium of the rectum in the mosquito larvae, Culex pipiens pallens: Culicidae, was observed with electron microscope. The rectum of posterior hindgut was composed of epithelial tissue which were covered with cuticular intima on the luminal side, connective tissue and muscular tissue. The rectal epithelial cells were squamous absorptive cells, and apical plasma membranes were highly folded to form apical infoldings with mitochondria inserted them. The lateral plasma membranes were irregularly infolded and well developed mitochondria were found closely associated with infoldings . And intercellular spaces (or channels) were formed between the epithelial cells, whereas speptate junction was found near the apical zone between them. Also basal plasma membrane were infolded which made basal infoldings ('basal labyrinth'), and were covered with thin basal lamina. Rcetal epithelium was surrounded by the connective tissue which was contained axon and tracheole cells. Connective tissue was covered with the bundles of circular and longitudinal muscles.

• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.694-700
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• 2018

To investigate the effect of heavy metals (Cu, Cd, Hg, Pb, Zn) on mosquito Culex pipiens, 50% lethal concentration ($LC_{50}$) concentration, total lipid content, lipid content composition, and total protein content were measured. The results showed that the Hg $LC_{50}$ was $0.45mg\;kg^{-1}$ and the Hg toxicity was higher than the other metals. The results also showed that cadmium (Cd) significantly retarded the growth of mosquito larvae among the tested heavy metals. Six types of lipid bands were isolated from mosquito samples exposed to heavy metals, and five of them were identified (phospholipid, cholesterol, fatty acid, triglyceride, and cholesterol ester). The total lipid content of all treatments decreased compared to the control. In addition, the protein content of the control group ($0.51mg\;ind.^{-1}$) was higher than that of the treated group, and the protein content of the larvae treated with Hg and Cd was very low. In conclusion, heavy metals not only lower the survival rate of mosquitoes, but also affect the protein content and lipids in the mosquito's body, thereby causing growth inhibition. These results indicate that heavy metal contamination will affect the size of mosquito population by inhibiting the survival and growth of mosquitoes, and it is expected that it can be used to measure the degree of contamination using mosquito through subsequent studies.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.243-249
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• 2005

We investigated the repellency of eight mosquito repellents against Culex pipiens pallens and Aedes albopictus, and the quantity of DEETs were analysed by using gas chromatography. Ae. albopictus showed higher bloodsucking efficacy than Cx. pipiens pallens of the two subjects mouse and human hands, and human hand was more efficacious method for mosquito bloodsucking efficacy than mouse. Among the eight repellents were tested with mouse as subjects for eight hours, product C, G, and H were high repellency than others. In the case of human hands as subject, product C was highly effective than above other products. The DEET quantities of eight repellants varied from 7.31 g to 38.9 g in 100 g contents and we ascertained that there was a correlation between mosquito repellency and the DEET quantities remained after the treatments. It was evidenced from the long term test with shirt piece, in this test the Ae. albopictus attack was increased when the DEET quantity decreased below 40%.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.139-150
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• 1985

In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

• Korean journal of applied entomology
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• v.47 no.4
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• pp.457-465
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• 2008

Eight Bacillus thuringiensis strains activated against mosquito larva were compared their characterization. Spherical-shaped parasporal inclusion of B. thuringiensis subsp. tohokuensis CAB167 was observed by phase-contrast microscopy and scanning electron microscopy. $LC_{50}$ values of B. thuringiensis subsp. tohokuensis CAB167 against Culex pipiens molestus, Culex pipiens pallens, and Aedes aegyti were 173, 190 and 580 ng/ml, respectively. B. thuringiensis subsp. tohokuensis CAB167 had a parasporal inclusion containing 4 major protein components, for example, 135, 80, 49 and 28-kDa by SDS-PAGE. Otherwise, after trypsin digestion of parasporal inclusion, SDS-PAGE was showed new protease-resistant peptides at 72 and 63-kDa. Activated toxins of isolated CAB167 were different from other reference strains on a serological by immuno-diffusion test.