• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.264-270
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• 2002

Studies on the resistance monitoring of green peach ahpid, Myzus persicae, its development pattern by artificial selection with imidacloprid and cross-resistance were carried out to develope resistance management strategy. Resistance ratios of M. persicae collected at Hwachon and Dunnae among 5 locations in alpine cultivation area appeared to be high as 37.2 and 16.5, respectively. Resistance of aphid to imidacloprid developed slowly up to 20 time selection, and after that it grew quickly. Imidacloprid-resistant aphid strain showed low cross-resistance ratios(<10) to most of organophosphates, carbamates, and mixed insecticides except pirimicarb(487.8), but high ratios to acetamiprid(143.0) which is one of the neonicotinoids like imidacloprid, and pyrethroids such as deltamethrin(14.9), flucythrinate(12.9) and halothrin(15.9).

• Korean journal of applied entomology
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• v.47 no.4
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• pp.369-378
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• 2008

After treatment with imidacloprid, there were clear differences in the time to the first reaction of Myzus persicae among the concentrations treated. The time taken for the proboscis of the aphids to penetrate, during the recording plants increased as the imidacloprid concentration increased. Imidacloprid concentration inflow into a leaf was investigated using high-performance liquid chromatography, and the residues of the imidacloprid varied slightly with the different concentrations treated. However, the inflow rates of this insecticide into a leaf increased as the dipping times increased. Furthermore, it was shown that there was no relationship in inflow concentration between the concentrations and times of treatment. However, the concentration in the leaf differed according to the dipping time. Judging from the fact that the first reaction behavior against imidacloprid displayed at an inflow concentration of 0.32-0.35 mg/L, we concluded that inflow concentrations causing the first reaction of the aphids to the insecticide were much lower than the concentration treated. The general feeding characteristics of the aphids indicated that xylem and/or phloem feeding behavior continued after a series of probing behaviors and stylet activity during the first 3 h from the start of EPG recording. After 90 min treatment with imidacloprid, feeding behavior over the next 30 min indicated a significant increase in the withdrawal of the stylet from the plant at all treated concentrations. Xylem and/or phloem feeding patterns were significantly decreased during this time. In particular, the proportion of xylem feeding differed according to the concentration of imidacloprid.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.397-403
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• 2012

This study compared the Aphelinus varipes and Aphelinus asychis in terms of how they parasitized the cotton aphid, Aphis gossypii and green peach aphid, Myzus persicae. Host-feeding, parasitism, emergence, the proportion of females and development time were all studied at 15, 20, 25 and $30^{\circ}C$ in controlled climate cabinets. When A. gossypii were provided for the two aphid parasitoids, the number of aphids killed by host-feeding for A. varipes (5.4 and 9.7 aphids) at $15^{\circ}C$ and $25^{\circ}C$ was higher than those for A. asychis (2.0 and 2.9 aphids). At $15^{\circ}C$ and $30^{\circ}C$, the parasitized A. gossypii were higher in A. varipes (11.1 and 21 aphids) than in A. asychis (7 and 12.3 aphids). The emergence rate was also significantly different between A. varipes (83.3%) and A. asychis (69.4%). The proportion of females was higher for A. asychis (75.2 and 73.9%) than for A. varipes (19.5 and 48.6%) at $15^{\circ}C$ and $30^{\circ}C$, respectively. No significant differences were found in development time between the two parasitoids. When M. persicae were provided for the two parasitoid species, the host-feeding number and the emergence rate of two parasitoids were not different at all four temperatures. The M. persicae were more highly parasitized by A. varipes (12.1 and 17.1 aphids) than by A. asychis (6.1, 10 aphids) at 20 and $25^{\circ}C$. The proportion of females for A. varipes (65.3 and 90.0%) was higher than that for A. asychis (34.4 and 78.8%) at $15^{\circ}C$ and $25^{\circ}C$. The development time from oviposition to the adult emergence of A. varipes (19.9 d) was significantly longer than that of A. asychis (16.5 d) at $20^{\circ}C$. Development times decreased with increasing temperature for both in two parasitoid species.

• Korean journal of applied entomology
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• v.32 no.2
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• pp.218-221
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• 1993

Sensitivities of insecticides and their seasonal variation were investigated against Myzus persicae. Some aphicides such as malathion were not effective on Myzus persicae in Chinese cabbage field. Difference of seasonal sensitivity was from I time to 16 times.

• 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.

• Journal of Applied Biological Chemistry
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• v.60 no.3
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• pp.271-277
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• 2017

Ethyl formate has been used for the control of insect pests by fumigation. However, there were not many reports to show its target site of fumigant toxicity on insect pests since its first use in the agricultural industry. In the present study, we showed the presumable target sites of ethyl formate fumigation in insect pests using Myzus persicae nymphs. After ethyl formate fumigation, the nymphs of this species were collected and the changes at the biochemical and molecular level were determined. The activity of cytochrome c oxidase (COX) was approximately two-fold higher after ethyl formate fumigation. In addition, the expression levels of acetylcholinesterase (AChE) decreased gradually with increasing ethyl formate concentration. These two findings suggested that COX and AChE might be the major target sites of ethyl formate fumigation. In addition to these results, the analysis of lipid content using MALDI-TOF MS/MS identified 9 phospholipids differently generated 2-fold higher in the ethyl formate-treated nymphs than that in the control nymphs, thereby leading to changes in cell membrane composition in M. persicae nymphs. Therefore, the ethyl formate fumigation caused lethal effects on M. persicae nymphs by changing COX activity, AChE gene expression, and phospholipid production.

• Korean journal of applied entomology
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• v.62 no.3
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• pp.155-160
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• 2023

In this study, we investigated the functional response of aphid parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae), on the green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae). Three carbon dioxide concentrations (400, 600, and 1000ppm) and seven host densities (2, 4, 8, 16, 32, 64, and 128) were used during a 24-h period. A type III functional response for A. colemani was fit separately for each CO₂ concentration. The estimated handling time (Th) under elevated CO₂ (600 ppm and 1000 ppm, 0.015 and 0.014 day) was shorter than that under ambient CO₂ (400 ppm, 0.017 day). The proportion of aphids that were parasitized showed the similar characteristic curve under three CO₂ concentrations. The highest parasitized rates for A. colemani were 0.57, 0.61, and 0.70 at 16, 32, and 32 aphid density under 400, 600, and 1000ppm, respectively. Although handling time of A. colemani was influenced by elevated CO₂ concentrations, the attach rate was not changed much.

• The Korean Journal of Pesticide Science
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• v.3 no.1
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• pp.84-89
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• 1999

This experiment was conducted to select the selective aphicides to Myzus persicae adults and its predator, Harmonia axyridis adults. The effects of the selective aphicides on the longevity, fecundity and hatchability of predaror were examined. All experiments were tested at the recommended concentration of those aphicides. Mortalities of adult H. axyridis to pirimicarb (162.5 ppm), fenvalerate (50 ppm) and endosulfan (577.5ppm) were shown 0, 20 and 22.5%, respectively. Endosulfan and fenvalerate showed the mortality above 48% to eggs and larvae H. axyridis, but pirimicarb was not toxic to those stages. Pirimicarb did not affect to the longevity, fecundity and hatchability of H. axyridis, but endosulfan and fenvalerate severely affected to the predators. From these results, pirimicarb can be used in biological controls for M. persicae.

• 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.35 no.3
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• pp.209-215
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• 1996

DNA polymorphisms were analyzed for 8 clones of the green peach aphid, Myzus persicae Sulzer, by random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). The insect has different host preferences and was even classified into two different species, M. persicae Sulzer and Myzus nicotinae Blackman by their morphological characters, but this point is still in arguement. To identify the differences between two types of the green peach aphid by RAPD-PCR, the template DNA was extracted from 4 clones each of tobacco-feeding and non-tobacco-feeding forms and one hundred primers of 10-nucleotideslong were tested in PCR. The amplified DNAs were analyzed by agarose gel electrophoresis. Eighty-three primers gave amplified DNA fragments with 1 to 22 in number and 500 to 20,000 base pairs in length, but no amplification was observed in the other 17 primers. The average number of fragment per each amplification was about 13. In the case of 82 out of 83 random primers, band patterns of amplified DNA were identical among 8 clones, even though some differences were noticed in the intensity of specific bands. Polymorphism was detected by only one primer within the tobacco-feeding forms, but not between the two host types. The results did not detect any relationship between RAPD polymorphism and their host preference.