Pyrifluquinazon, as a quinazinalone chemical group, based on a new mode of biological activity. It is reported that mode of action is modifies insect behavior, rapidly stopping feeding such that insects starve to death. Time-release feature and mortality effect on M. persicae using different pyrifluquinazon nano type and non-nano type were compared. Pyrifluquinazon nano type was formulated with different molecular weight and density of used chitosan (CS 30000 0.1% and CS 3000 0.3%). In the CS 30,000 0.1%, the mortality was weakly occurred at early time, but steadily increased after 4days. Finally, we confirmed more than 70% mortality as a peak at 16days. In CS 3000 0.3%, the mortality showed about 70% until 18days as a effective controlled release. Also, We examine time-release feature and mortality effect on M. persicae according to the different pyrifluquinazon nano type(CS 30000 0.1% and CS 3000 0.3%) of concentrations. The CS 30000 0.1% bioassay results of different concentration were showed that the highest concentration(100ppm) was measured better mortality than other concentration at 0 day, but cannot confirm different effect about dissimilar concentration. However, increasing rates of M. persicae were low as treatment concentrate was high. In CS 3000 0.3% 100ppm concentration bioassay result, aphid mortality reached peak at 24 days and increasing rate also low. Additionally, for the comparing of bioassay and feeding behavior of M. persicae against pyrifluquinazon nano types and non-nano type, EPG technique was carried out. In case of non nano type, feeding inhibition efficacy was showed during 4 days after treatment, but appeared similar level with control after 10days. In CS 3000 0.3% 50ppm, residual efficacy was specially showed until 28days after treatment whereas treatments with CS 30000 0.1% were similar to the control after 22days. These result show that the change of feedinng behavior and motrality of M. persicae is correlated with the change of nano type or non nano type of pyrifluquinazon.

Plant penetration by aphids can be monitored electrically by the electrical penetration graph (EPG) technique. To confirm whether some behaviors are correlated to specific graph pattern in EPG, we analyzed the two synchronized data, EPG and video records. We recorded electrical penetration graph (EPG) and behaviors of aphids simultaneously. Then we compared the behaviors of aphids with the recorded EPG waveforms in order to match their visible behaviors and invisible behaviors with stylet. The visible behaviors were categorized for walking, wagging, honeydew production, and reproduction. When the aphids were generally motionless, the EPG denoted feeding-related waveforms (E1, E2, F and G). Whereas, probing waveforms (B and pd) frequently occurred when they were wagging. We aim to present the correlation between observed behaviors and EPG patterns.

The Green Peach aphid, Myzus persicae Sulzer, is one of the most widespread insect pests worldwide. We established the ethogram of this species during the pre-reproductive period to understand the behavioral repertoire, organization of behaviors, and the context in which they occur. The behaviors that we observed include honeydew production (HDP), walking, wagging, pre-molting and molting. We noted the frequency and the amount of time for each behavior at different nymphal stages. As the nymphal stage increased, the rate of HDP decreased. The HDP seemed to occurred at regular duration and interval in each nymphal stage, while the wagging and walking seemed to be irregular behaviors. When wagging occurred before HDP, the successive HDP was significantly delayed, suggesting that aphids might not feed during wagging. Due to regularity through all nymphal-stages, HPD can be used for a good behavioral indicator in the related bioassay.

The green peach aphid, Myzuspersicae Sulzer, is one of the most important insect pest in the world. To assess the efficiency of sound wave to control aphids, we treated a different combination of intensity (66dB, 78dB, 90dB) and frequency (100Hz, 500Hz, 1000Hz) of acoustic stimulus to the aphids. Then we analyzed aphid’s behaviors occurred in each different combination group of acoustic stimulus and control group, and compared them to confirm the most effective sound. We used honey-dew-production (HDP) for behavioral bioassay, which occurs regularly in each nymphal stage and adult period. The rate of HDP decreased in the whole experimental group when compared with control group (F1,358=79.415,P<0.0001). The most effective acoustic frequency was100Hz in which aphids reduced the rate of HDP to approximately 1/3 times lower than that of control group. The treatments of 1000Hz and 500Hz were effective in the order of appearance. The effect of acoustic stimulus seems irregular in the different intensities, and the highest intensity did not show the strongest effect in each frequency. Consequently, the rate of HDP seemed to be affected by the acoustic frequency more than the intensity.

Four major agricultural insect pests, Bemisia tabaci, Myzus persicae, Plutella xylostella and Tetranychus urticae, were irradiated with 30, 50, 70, or 100 Gy electron-beam. Longevity, egg hatching, emergence, and fecundity of the test insects were measured. Hatchability of B. tabaci, P. xylostella and T. urticae declined with increasing irradiation doses, and all B. tabaci and T. urticae eggs were dead at 100 Gy. When eggs of B. tabaci, P. xylostella and T. urticae were irradiated, hatch was inhibited. B. tabaci adults grown from 70 Gy irradiated eggs did not lay eggs. Fecundity of P. xylostella from the 100 Gy irradiated eggs decreased. When B. tabaci, P. xylostella, M. persicae and T. urticae nymphs/larvae were irradiated, the results were similar as those of the hatched eggs. When P. xylostella pupae were irradiated with 100 Gy, fecundity of emerged adults decreased and no eggs hatched. When B. tabaci, P. xylostella, M. persicae and T. urticae adults were irradiated with 70 and 100 Gy, fecundity decreased and egg hatch of B. tabaci was inhibited. However, the longevity of adults did not change and electron-beam irradiation of all developmental stages had no effect on the longevity of adults.

The green peach aphid, Myzus persicae (Sulzer), is one of the most serious pest in cabbage cultivation. Field survey was carried out to know the insecticide resistance levels in five main cabbage cultivation regions (Pyeong-chang, Hong-cheon, Bong-wha, Mu-ju and Je-ju) in 2009. The green peach aphid can resist a wide range of insecticides in five surveyed local populations. Among the nine tested insecticides, four chemicals (methomyl, bifenthrin, pymetrozine and flonicarmid) showed less than 50% mortality in the recommended concentration in all populations. Multi resistant (MR) strain was selected from these populations and esterase over-expression, modified AChE (MACE) and mutation(s) in para-type sodium channel were analysed using native IEF and quantitative sequencing with five local populations. Esterase over-expression and MACE (StoF mutation) were observed in all populations including MR strain. LtoF mutation is well known as a kdr mutation in para-type sodium channel. However, even though LC50 values of MR strain noted over 2,000 times higher than that of susceptible strain against bifenthrin, any mutation was not detected in para type sodium channel and also local populations. These results suggested that unusual case could be existed in pyrethroid resistance mechanism in green peach aphid.

Developmental time, mummification, pupal mortality, sex ratio of a South Korean strain of Aphelinus varipes Förster parasitizing the green peach aphid, Myzus persicae were studied at 20, 25 and 30℃ in controlled climate cabinets. Plastic container with sweet pepper(Capsicum annuum L.) were used as experimental units. Green peach aphid in different larval instars and as adults, reared at the three different temperatures, were presented to A. varipes in a 'no-choice' and 'choice' situation for 6h. These presentations were done at 25℃ in each experiment to avoid an influence of temperature on parasitization rate. In case of no-choice test, more 1st(24%), 2nd(22%) and 3rd(38%) instar aphids were parasitized than 4th(14%) instar and adult(10%) among the aphids reared at 25℃. In case of choice test, more 1st(41%), 2nd(42%) and 3rd(29%) instar aphids were parasitized than 4th(13%) instar and adult(0%) among the aphids reared at 25℃. Pupal mortality of the parasitoid was not influenced by temperatures. The sex ratio of A. varipes was male-biased, and varied between 49.4% females developed from aphids reared at 30℃ and 42.8% from aphids reared at 20℃. The sex ratio was not significantly influenced by host stages. The developmental time of A. varipes parasitizing the green peach aphid ranged from 26.1days at 20℃ to 11.1days at 30℃.

Myzus persicae, Heliothis assulta and Frankliniella occidentalis are the most severe pests of pepper in Korea. IPCC (Intergovernmental Panel on Climate Change) reported that the temperature would increase 7℃ at the end of this century. According to the elevated temperature, the pest population will be grow dramatically. We need to predict the pest-population size to maintain good crop productivity. DYMEX and CLIMEX are commercial software developed by CSIRO in Australia, to build and simulate population dynamics models. Using this software, we predicted population dynamics of M. persicae, H. assulta and F. occidentalis applying past climate data (1970) and future climate data (2070) which were generated by National Institute of Meteorological Research (NIMR). The population growth rates of M. persicae, H. assulta and F. occidentalis were 6300, 16 and 950 times, respectively, with 5 degree elevation. Therefore pest management should be conducted intensively in the future.

The green peach aphid, Myzus persicae, is one of the most widespread insect pest worldwide. We documented all behaviors of this species during the pre-reproductive period to understand the behavioral repertoire, organization of behaviors, and the context in which they occur. The behaviors that we observed include honey-dew production, walking, wagging, and molting. Honey-dew production occurred regularly at every 30-60 min throughout all nymphal stages. Walking seemed to occur when the host condition was not good, probably related to searching for a new host. Wagging, which was the turning of abdomen with the stylet in the plant, was also frequently observed, but the function of this behavior was unclear. We also noted the frequency and the amount of time for each behavior at different nymphal stages.

To investigate resistance of Myzus persicae, which is resistant to etofenprox belonging to pyrethriods, to other insecticides, fenpropathrin and thiamethoxam, mortality and LC₅₀ values for these two insecticides against the etofenprox-resistant and -susceptible populations were obtained and EPG analysis for feeding behaviors of thiamethoxam or fenpropathrin treated and non-treated M. persicae was conducted. For fenpropathrin, mortality after 48 h treatment was 28 and 29%, respectively for the resistant and susceptible population. The LC₅₀ value was 193.15 and 93.46 ppm, respectively. For thiamethoxam, mortality after 48 h treatment was 87 and 57%, respectively for the resistant and susceptible population. The LC₅₀ value was 3.17 and 30.34 ppm, respectively. There was no significant difference in feeding behavior between fenprorpathrin treated and non-treated M. persicae. They showed a continuous feeding pattern. However, contact signal frequency increased in the thiamethoxam treated M. persicae 1 hour after treatment and significant difference was shown.

Myzus persicae, Heliothis assulta and Frankliniella occidentalis are major pepper pests in Korea. The objective of this study was to assess the pepper-yield decrease caused by population change of M. persicae, H. assulta and F. occidentalis. with temperature elevation. It is easy to expect that climate change will increase crop damage caused by pests. Therefore we should predict pest-population dynamics exactly and find the best available strategy for the pest management. Based on the many reported results of temperature development of the three kinds of pest, we simulated the future population dynamics using the computer softwater, DYMEX, developed by CSIRO. The results were that the population sizes and outbreak frequency of 3 kinds pest would increase with global warming. This work may be helpful to establish an effective pest management.

This study was performed to investigate the correlation between changes of feeding behavior of green peach aphid, Myzus persicae and residual effect of an insecticide, Pyrifluzuinazon, using EPG technique. Pyrifluquinazon was showed the insecticidal activity until three days (72h) after treatment, and the activity was high in nymph than adult of GPA. There was no difference among treatment methods. Lethal sign was observed the slimed the abdomen of GPA after 3 days that rises the insecticidal activity, and dieㅇ as being sticked and/or pulled out the needle. Residual efficacy from 1, 3, 5, 7 to 20 days after treatment, insecticidal activity was showed 70% in 50 ppm, recommended concentration, until 5 days. And waveforms relating to non-probe time and phloem phase time using EPA, feeding inhibition efficacy was showed during 5 days after treatment, but showed similar level with control after 13 days. These results show that the change of feeding behavior of GPA is correlated with the change of residual effect of pyrifluzuinazon.

For the comparing of mortality of the resistance and susceptible population of Myzus persicae, etofenprox was treated in the recommended concentration of 200ppm. Mortalities of resistance population were 16.7 and 36.7%, and susceptible population were 86.7 and 86.7% after 24 and 48 hours treatment, respectively. For the detect of cross resistance to other pyrethroids, 6 pyrethroids were examined. Mortalities of susceptible and resistance populations were 90 and 31% to deltamethrin, 92 and 23% to lambda cyhalothrin, 81 and 14% to cypermethrin, 70 and 20% to α-cypermethrin, 29 and 28% to fenpropathrin, 84 and 29% to fenvalerate, respectively. It was showed that resistance populations were generally resistive to other pyrethroids. On the other hands, for recognized ecological characteristic of M. persicae susceptible and resistance populations life table was tested on the pepper leaves in the petri dish and on the plant in the pot. This results were showed that intrinsic rate of increase (r<SUB>m</SUB>), net reproduction number (R₀) and generation time in day (T<SUB>c</SUB>) were significantly different between two population in both tested. However, life span and reproduction period were slightly different between them. Otherwise, feeding behaviors were tested using EPG technique with non- and treated etofenprox. First potential drop time of susceptible and resistance population was 73.5 and 257.9 sec with non-treated and 93.3 and 1076.2 sec after treated, respectively. Electrical probing signals were 8.2 and 48.8 times with susceptible and resistance individuals after treated etofenprox, respectively. It was supposed that the resistance is more probings than susceptible population. After treated, total feeding time have more 6,728.9 sec on resistance than 965.5 sec on susceptible population. So, total non penetration time of susceptible population was 3,000 sec longer than resistance population.

The changes of feeding pattern and the amount of insecticide penetrated into the leaf were monitored for 420 min after treatment of three concentrations of dinotefuran. At about 30 min after treatment of insecticide, the overall feeding pattern in EPG (Electrical Penetration Graph) monitoring was started to change, and there was significant difference in proportions of NP (non-penetration), PA (pathway activity), and phloem-feeding patterns among the different concentrations of dinotefuran treatment. Especially, as the amount of insecticide penetrated into a leaf increased, the reactive behaviors against this insecticide such as withdrawal of proboscis and movements of stylet of aphid were more quickly exhibited. And also, total time at which the proboscis of the aphids did not penetrate the plant was getting longer. The amount of dinotefuran penetrated into a leaf was monitored with HPLC. When the recommended concentration (100 ㎎/L) of the insecticide was treated, 5.24~7.24 ㎎/L of the insecticide was detected from the leaf, and the proboscis of the aphids was apparently withdrawn from the leaf at approximately 60 minutes after treatment of this insecticide.

바이러스 내병성 인자가 도입된 GM 고추 품종과 Non-GM 품종에서의 복숭아혹 진딧물의 생활사를 비교, 조사하였다. 온도 23℃, 광주기 16:8(L:D)로 조절된 실 험조건 하에서 한 배에서 출생한 1령 약충을 GM(15), Non-GM(2377)품종의 고 추 잎당 1마리씩 접종하여 우화 후 성충이 사망할 때까지 출산수를 24시간 간격으로 조사하였다. 복숭아혹진딧물의 수명은 Non-GM 품종과 GM 품종에서 각각 26.88±5.42일 과 25.92±8.18일로 Non-GM에서 길었으나 유의한 차이를 보이지는 않았다 (t=0.55; df=61; P>0.05). 출산수 또한 Non-GM과 GM 고추 품종에서 각각 63.5±15.75일, 66.59±17.63일로 GM 품종에서 많았으나 유의한 차이를 보이지 는 않았다(t=0.72; df=61; P>0.05). 두 고추 품종에서 복숭아혹진딧물의 전출산 기간은 각각 6.41±047일, 6.18±0.54일로 Non-GM에서 다소 길게 나타났으나 유 의한 차이는 아니었다(t=1.08; df=61; P>0.05). 또한, 각 고추 품종에서 복숭아 혹진딧물의 내적자연증가율, 세대기간, 순증가율, 계차증가율 등에서도 유의한 차이가 없는 것으로 추정되었다(내적자연증가율: t=0.83; df=61; P>0.05, 세대기 간: t=0.1; df=61; P>0.05, 순증가율: t=0.54; df=61; P>0.05, 계차증가율: t=0.45; df=61; P>0.05).

Geographic clines in genetic polymorphisms are widely believed as an evidence of climate change. We hypothesized green peach aphid, Myzus persicae Sulzer, one of the major insect pests in highland chinese cabbage cultivation, may also have some interactions with climate change. As the first step, we tried to find the available markers from six local strains (five collected at different heights in Hoengseong and Pyeongchang area and one from laboratory). A strain from Jeju island was used as an out-group. Although there was no significant difference in sequences of partial ribosomal RNA fragment and mitochondrial cytochrome oxidase I, and esterase isozyme pattern, we found four inter-simple sequence repeat (ISSR) markers in 22 used ISSR primers (+AGA, +CCA, +CGA, CGA+). These primers can be used as good markers to trace the M. persicae gene flow because they showed specific bands according to local strains.

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 ㎎/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.

This study was conducted to estimate the economic injury level (EIL) and economic threshold (ET) of the green peach aphid, Myzus persicae, on Chinese cabbage (Brassica campestris var). The changes of biomass of Chinese cabbage and M. persicae density were investigated after introduction of M. persicae at different density (0, 2, 5, 10, 15, and 20 per plant, inoculated at 10d after planting). The densities of M. persicae largely increased from the above initial densities to 0, 92.3, 177.4, 406.9, 440.4, and 471.3 aphids per plant at 18d after the initial inoculation, respectively. The biomass of Chinese cabbage significantly decreased with increasing the initial inoculated density of M. persicae: 602.0, 264.2, 262.0, 109.3, 151.0, and 67.3 g in above plots with different initial densities, respectively. The relationship between cumulative aphid days (CAD) and yield loss (%) of Chinese cabbage was well described by a nonlinear logistic equation. Using the estimated equation, EIL of M. persicae on Chinese cabbage was estimated 25 CAD per plant based on the yield loss 13%, which take into account of an empirical gain threshold 5% and marketable rate 92% of spring Chinese cabbage. Also, ET was calculated at 80% of EIL: 20 aphids per plant. Until a more elaborate EIL-model is developed, the present result may be useful for M. persicae management at early growth stage of Chinese cabbage.

As indigenous aphid parasitoid, Aphelinus varipes kill aphids for feeding in addition to parasitization. Because of this characteristic of A. varipes, this parasitoid may have the possibility of biological control agent against aphids. So we have evaluated traits such as daily paratization, total parasization, number of aphids killed by host feeding, sex ratio, development time, pupal mortality of A. varipes parasitizing green peach aphid, Myzus persicae. At 25°C and 16L:8D, longevity, total paratization and host feeding of A. varipes female was 11.0, 25.3, and 63.3 days, respectively. And development time of male and female, sex ratio (M:F), pupa mortality of offspring of A. varipes were 12.0 days, 12.5 days, 0.88, and 11.6%, respectively. However, because these results are not enough to estimate potential of A. varipes as biological control agents/factors, other factors such as host suitability (Macrosiphum euphorbiae, Aulacorthum solani), effect of temperature, and host seeking behavior of A. varipes continually will be investigated.

To assess the environmental risks of transgenic chili pepper with PepEST gene on non-target organisms before it exposes to the agro-ecosystem environments, we conducted the three sets of green peach aphids (Myzus persicae S.) life table experiment under laboratory conditions (Temp. 25℃, R.H. 50-70%, Photoperiod L16 : D8) in series during 2005-2006. We measured the net reproductive rate (R₀)*, the intrinsic rate of increase (r<SUB>m</SUB>), the mean generation time (T<SUB>c</SUB>), fecundity*, life span, and reproduction period between non-transgenic chili peppers and transgenic chili peppers, respectively. The life span of green peach aphids from three sets was 31, 27, 25 days, and the period of life span was similar to the general average length of green peach aphids, 25-29 days. Although the first reproduction of transgenic pepper was similar to the non transgenic pepper (P＞0.05), the fecundity and the net reproductive rate (R<SUB>o</SUB>) by using Jackknife method of transgenic pepper were lower than those of non transgenic pepper (P＜0.05). Conclusively, we observed the adverse effect from our results but we should execute further experiments to confirm the results at the fields with the similar way.