• Korean journal of applied entomology
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• v.40 no.1
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• pp.44-49
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• 2001

Development and predation of an aphidophagous gall midge, Aphidoletes aphydimyza (Rondani) , on the green peach aphid, Myzus persicae Sulzer, were studied under laboratory and greenhouse conditions. The developmental threshold temperature of the gall midge larvae was estimated to be $13^{\circ}C$. Larval and total developmental periods were 5.3 and 29 days at 25 $\pm$$2^{\circ}C$. The gall midge attacked more aphids as increasing density of peach aphids, and consumed 4 out of 10 peach aphids per day in a petri dish (9 cm in diameter) at maximum. In green house, the gall midge could control the density of the green peach aphids efficiently with a delayed density dependent-like pattern.

• Korean journal of applied entomology
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• v.16 no.2 s.31
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• pp.93-100
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• 1977

This is the fist report on detailed aphid transnsmission studies of cruciferous virus in Korea, and experiments aimed to get basic informations for control of vectors. Aphid transmission of turnip mosaic virus prevalent on radish in the field was studied. Results obtained were as follows: 1. Myzus persicae, Lipaphis erysimi, Aphis gossypii and Aphis craccivora were found to transmit turnip mosaic virus. 2. The proper time for turnip mosaic virus transmission by Myzus persicae was 1 hour of fasting, 3 minutes for acquisition, and 1 minute for inoculation: Lipaphis erysimi was 2 hours for fasting, 5 minutes for acquisition, and 3 miuutes for inoculation: while Aphis gossypii needed 1hour for fasting, and 3 minutes for each of the acquisition and inoculation periods. 3. There was Po great difference in probing patterns between nonfasted and fasted aphids for 2 hours. All the fasted aphids began feeding after 4 minutes, 4. When Myzus persicae were transferred artificially at 1-2 minute intervals, the number of probes with aphids fasted for 2 hours was much greater than that of nonfasted aphids. Aphids fasted for 2 hours mainly transmitted the virus before 4 minutes, with an acquisition feeing period of less than 3 minutes

• Animal cells and systems
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• v.5 no.3
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• pp.163-177
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• 2001

Most, if not all, aphids harbor intracellular bacterial symbionts, called Buchnera, in their bacteriocytes, huge cells differentiated for this purpose. The association between Buchnera and aphids is so intimate, mutualistic and obligate that neither of them can any longer reproduce independently. Buchnera are vertically transmitted through generations of the host insects. Evidence suggests that Buchnera were acquired by a common ancestor of aphids 160-280 million years ago, and have been diversified, since then, in parallel with their aphid hosts. Molecular phylogenetic analyses indicate that Buchnera belong to the g subdivision of the Proteobacteria. Although Buchnera are close relatives of Escherichia coli, they contain move than 100 genomic copies per cell, and their genome size is only one seventh that of E. coli. The complete genome sequence of Buchnera revealed that their gene repertoire is quite different from those of parasitic bacteria such as Mycoplasma, Rickettsia and Chlamydia, though their genome sizes have been reduced to a similar extent. Whereas these parasitic bacteria have lost most genes for the biosynthesis of amino acids, Buchnera retain many of them. In particular, Buchnera's gene repertoire is characteristic in the richness of the genes for the biosynthesis of essential amino acids that the eukaryotic hosts are not able to synthesize, reflecting a nutritional role played by these symbionts. Buchnera, when housed in the bacteriocyte, selectively synthesize a large amount of symbionin, which is a homolog of GroEL, the major stress protein of E. coli. Symbionin not only functions as molecular chaperone, like GroEL, but also has evolutionarily acquired the phosphotransferase activity through amino acid substitutions. Aphids usually profit from Buchnera's fuction as a nutritional supplier and, when faced with an emergency, consume the biomass of Buchnera cells as nutrient reserves.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.1
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• pp.27-33
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• 2012

This study was performed in the Tropical Plant Resources Research Center of Korea National Arboretum to assess the effects of natural enemy attack on aphid population feeding on tropical plants. We measured the density of leaf-feeding aphids, Myzus persicae and Aphis gossypii, cohabiting with 5 types of tropical plants at intervals of approximately 2 weeks after introducing their natural enemy, Aphidius colemani. The density of aphids cohabiting with 4 types of tropical plants-Sanchezia parvibracteata, Hibiscus rosa-chinensis, Ficus kurzii, and Aloysia triphylla-started decreasing after 2 weeks of observation and was completely in control after 4 weeks of observation; however, the density of aphids cohabiting with the tropical plant, Hamelia patens, increased during 22 weeks of observation but decreased after the $23^{rd}$ week of observation. We suggest that a banker plant is necessary for the maintenance of A. colemani in tropical greenhouses, and monitoring studies on H. patens, which was weakest against the aphids, should be performed. Our results indicate that biological pest management strategies using their natural enemies were formulated for the construction of new tropical greenhouses.

• Korean Journal of Environmental Biology
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• v.19 no.4
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• pp.254-260
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• 2001

After investigating the developmental process of galls forming on leaf of Zelkova serrata and analyzing the composition and contents of the free amino acids in leaves, galls and haemolymph of aphids, we have come to the following results. Galls induced were mostly distributed on the middle of lower part of leaf to the petiole along vein and most of investigated leaves had one gall only. The growth of galls continued in length and width until Paracolopha morrisoni habitants which transformed into alate adult left the gall. These results also indicate that galls are closely connected with a portion of plant tissues as well as foods and habitats of aphids. 26${\sim}$29 kinds of free amino acids such as proline, alanine and valine and so on, detected in leaves, gall and haemolymph of aphids. The composition of free amino acids were similar in three materials examined, but proline and asparatic acid showed the highest quantity in the leaves and falls, respectively. In case of aphids, alanine was extremely higher as 18.4% of total contents of free amino acids, in 1st instar of fundatrix stage. Total contents of free amino acids in the apteral adult stage of aphid were also increased than in the 1st instar stage. This investigation implies that nitrogen source such as free amino acids is apparently a major growth-material like carbohydrates during development of galls in Zelkova serrata.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.45-45
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• 2001

Development and predation of an aphidophagous gall midge, Aphidoletes aphydimyza (Rondani) , on the green peach aphid, Myzus persicae Sulzer, were studied under laboratory and greenhouse conditions. The developmental threshold temperature of the gall midge larvae was estimated to be $13^{\circ}C$. Larval and total developmental periods were 5.3 and 29 days at 25 $\pm$$2^{\circ}C$. The gall midge attacked more aphids as increasing density of peach aphids, and consumed 4 out of 10 peach aphids per day in a petri dish (9 cm in diameter) at maximum. In green house, the gall midge could control the density of the green peach aphids efficiently with a delayed density dependent-like pattern.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.365-372
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• 2012

Native of soybean aphid (Aphis glycines Matsumura) is an Asia and aphid is one of the dangerous pests in soybean [Glycine max (L.) Merr.]. High density aphid populations can reduce crop production by causing severe damage. The objective of this study was evaluation of resistance to the soybean aphid in soybean cultivars and germplasms. A total of fifty five soybean cultivars or germplasms, including two susceptible and two resistant check varieties, were infested to evaluate their resistance in the field cage and greenhouse test by aphid colonies which derived from wild collected one soybean aphid biotype in Korea. The average number of reproduced soybean aphid was evaluated with 62.7 aphids in the resistant check variety PI 567598B and also estimated with 1,807 aphids for susceptible check variety Williams 82. In soybean varieties and germplasms, the average reproduced soybean aphid populations ranged from the lowest 497 aphids for Junjeori to the highest 3,862 aphids for Mansu. About seventy six percent of soybean cultivars and germplasms were shown high density soybean aphid populations when compared with another susceptible check variety PI 567543C in the field cage test. From the greenhouse test to evaluate aphid index, 87.3% of soybean cultivars or germplasms presented aphid index with 9.0. No soybean cultivars and germplasms were observed with soybean resistant phenotype when regarded a aphid resistant level as less than 10% aphid reproductions compared with susceptible check Williams 82. Although no Korean soybean cultivars were identified with resistant trait to the soybean aphid, we found one great resistant genetic resource PI 567598B in this study. This result will be helpful to further study for providing useful genetic information for soybean researchers.

• The Korean Journal of Pesticide Science
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• v.14 no.4
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• pp.415-420
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• 2010

This study investigated effects of different sound frequencies on development and insecticide susceptibility of the green peach aphid, Myzus persicae. Under a constant sound intensity (95 dB), different frequency (0-5,000 Hz) sounds were treated on entire developmental period of the aphids. With increase of sound frequencies, nymphal to adult development of the aphids showed significant retardation and the females exhibited a significant decrease in fecundity. The greatest disrupting effects were induced by treatment of 5,000 Hz, which also caused marked change in protein expression of the aphids analysed by two dimensional electrophoresis. Sound frequencies above 2,000 Hz significantly increased susceptibility of the aphids against imidacloprid. This study clearly suggest that there is a stress sound, which can be sensed by M. persicae and induces its physiological alteration.

• Korean Journal of Environmental Agriculture
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• v.29 no.3
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• pp.239-246
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• 2010

Aphids are one of the major pests in agricultural crops. A number of synthetic pesticides have been used for control of aphids in agriculture, but increasing public concerns over their adverse effects on the environment have required more environmentally-friendly methods for pest management. In this study, we examined plant oil formulations for the control of green peach aphid (Myzus persicae). Oil formulations were prepared by hydrolyzing the plant oils in ethanolic KOH solution and diluted at the rate of 1:500 for aphid control. The oil formulations showed aphid mortalities ranging from 24.44 to 43.33% in vitro. Significantly increased aphid mortalities were observed by the treatment of oil formulations combined with low-dosed imidacloprid. No significant difference in the aphid mortality was observed between the oil formulations. Mass spectrometry analyses of aphids treated with the low dosedimidacloprid plus the plant oil formulations detected similar concentrations of imidacloprid between the treatments. In field trial bioassays against aphids, significantly decreased aphid population were observed in the pepper plants treated with soybean oil formulation combined with the low-dosed imidacloprid, while aphid population dramatically increased in the pepper plants treated with the low-dosed imidacloprid alone. These results suggested that the plant oil formulations can be used as an environmentally-friendly method for enhancing the insecticidal effectiveness, which may play a role in reducing the use of synthetic pesticide in agriculture.

• Journal of Microbiology and Biotechnology
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• v.18 no.12
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• pp.1915-1918
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• 2008

An entomopathogenic fungus was isolated from an infected aphid. The isolate conformed most closely to Lecanicillium attenuatum CBS 402.78 (AJ292434) based on the internal transcribed spacer (ITS) region of its 18S rDNA, and thus was designated L. attenuatum CNU-23. Laboratory and field evaluations of CNU-23 blastospores were carried out for the control of green peach aphids. The laboratory evaluations of CNU-23 revealed an aphid mortality of about 80% with an estimated $LT_{50}$ of 3.72 days after the application of CNU-23 at $1{\times}10^6$ blastospores/ml. Meanwhile, the field evaluations of CNU-23 performed on greenhouse pepper plants during the rainy season showed an aphid mortality ranging from 72% to 97%. Significant sporulation was observed in the aphids treated with CNU-23. Therefore, the results suggest that L. attenuatum CNU-23 can be used as a biocontrol agent for green peach aphids on greenhouse pepper plants.