An aphid usually stays at one feeding site for a long time for development and reproduction. The green peach aphids, Myzus persicae (Sulzer), feed consistently and regularly throughout all stages of nymphs and adult at one feeding site. In M. persicae, honey dew production, which indicates a state of feeding, occurs at regular intervals within a given stage, and moving, which may be related to escape or dispersal, interrupts feeding, The results of the playback experiments showed that acoustic stimuli with frequencies of 100 and 10000 Hz were effective in inducing feeding repression in M. persicae. That is, HDP occurred less often, and MV occurred more often and longer under acoustic stimuli. In this study, we tested whether the acoustic stimulus effective for inducing feeding suppression decreased reproductive rate in M. persicae. A group of 20 aphids were placed in a host plant and was subject to the acoustic stimulus with two frequency components, 100 and 10000 Hz, for a given time (1, 3, 6, and 12 hours) each day for four days. The result of this experiment showed that the acoustic stimulus did not affect the reproductive rate, regardless of exposure time, in M. persicae.

To identify whether higher expression of carboxylesterase (CbE) E4 in Myzus persicae is due to gene duplication, gene copy number was determined by quantitative real-time PCR. In addition, to determine the actual protein concentration of CbE E4 and it activity, Western blotting and activity staining were conducted. CbE gene copy number was highly correlated with carbamate resistance ratio (r2=0.934). However, CbE E4 expression level was little correlated with insecticide resistance ratio (r2<0.046) and no apparent correlation was observed among the gene copy number, protein quantity and total activity of CbE E4. Therefore, it was assumed that not only quantitative changing but also qualitative alteration of CbE E4 occurred in M. persicae. To investigate any potential alteration of CbE E4, mutation survey was conducted by sequencing of CbE E4 from various local strains of M. persicae. G137D and W251L mutations have been known as the main mutations associated with structural change leading to resistance. Interestingly, a new G134C mutation, which is in proximity of G137D mutation, was identified in the oxyanion hole of CbE E4. To predict the functional role of this mutation in resistance, 3-dimensional structure modeling was conducted. In summary, CbE E4 appears to be involved in resistance to both pyrethroids and carbamates as a nonspecific hydrolase or sequestration protein in M. persicae.

The green peach aphid, Myzus persicae (Sulzer), is one of the most serious pests in cabbage cultivation. Field survey was carried out to know the insecticide resistance levels and to develop the applicable insecticide resistant markers in five main cabbage cultivation regions (Pyeong-chang, Hong-cheon, Bong-wha, Mu-ju and Je-ju) during 2009 to 2011. M. persicae can resist a wide range of insecticides in five surveyed local populations. Therefore multi resistant (MR) strain was selected from these five local populations and esterase over-expression, modified AChE (MACE) and mutation(s) in para-type sodium channel were analyzed 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, LtoF mutation was not detected in para type sodium channel and also local populations. We found another mutation (MtoL) in para and that mutation highly correlated between mutation ratio and bioassay data. For preliminary resistance monitoring, we developed quantitative sequencing (QS) to detect the frequencies of point mutation as a population genotyping. These methods can apply to manage M. persicae resistant populations in field.

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 2009~2011. 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 60% mortality in the recommended concentration in most years of local populations. Multi resistant (MR) strain was selected from these populations and modified AChE (MACE: StoF mutation), MtoL mutation in para-type sodium channel, esterase over-expression were observed in almost of all populations including MR strain. Especially, StoF and MtoL mutations were highly correlated with resistance ratio and population based quantitative sequencing results. Therefore, these results suggested that molecular-biology based resistance monitoring can applied resistance management in M. persicae.

The green peach aphids, Myzus persicae (Sulzer), feed consistently and regularly throughout all stages of nymphs and adult. That is, honey dew production (HDP), which indicates a state of feeding, occurs at regular intervals within a given stage, and moving (MV), which interrupts feeding, tends to occur scarcely. We used these behaviors to test whether the sound stimuli acted as a stress in this species. We conducted the playback experiment in which acoustic stimuli with a combination of five frequency (100, 500, 1000, 5000, and 10000 Hz) and three intensity levels (66, 78, 90 dB SPL) were presented to all stages of aphids. Under all acoustic stimuli, HDP occurred less often, and MV occurred more often and longer. The results of two-way multivariate ANOVA showed that the stimulus frequency was a significant factor for variation in aphid behaviors in the playback experiment. However, there was no intensity effect on aphid’s behavior. Based on the electrical penetration graph experiment, aphid feeding was frequently stopped and lasted only for short durations under acoustic stimuli. The results of both experiments demonstrated that the acoustic stimuli were effective in inducing feeding suppression in this species. Thus, the acoustic stimuli may be a stressor in the green peach aphid. Furthermore, the behavioral bioassay employed in this study may be used to assess the effect of various stressors on aphids.

 ,  , This study focused on the green peach aphid, Myzus persicae, as an indicator pest in Chinese cabbage cultivation to develop a genetic marker. We hypothesized that M. persicae gene flow is related to climate change. Genetic variation was analyzed using five local populations collected at different altitudes (157 m, 296 m, 560 m, 756 m and 932 m above sea level) in Hoengseong, Pyeongchang, and Gangneung areas, plus a laboratory strain used as an outgroup. There were no differences in ecological characteristics among strains. Esterase isozyme pattern and inter-simple sequence repeat (ISSR) PCR results showed significantly different bands between laboratory and wild, local populations. However, there was no difference among local populations. Partial fragments of ribosomal RNA (rRNA) and mitochondrial cytochrome oxidase I (mtCO I) were amplified and their nucleotide sequence was analyzed. Single nucleotide polymorphisms (SNPs) were detected in internal transcribed spacer-2 (ITS-2) and mtCO I regions among the five local populations. These SNPs can be use to discriminate different populations of M. persicae to monitor gene flow.

 ,  , To investigate host preferencse of Myzus persicae on 15 sweet pepper cultivars grown in Jeonnam Province, EPG (electrical penetration graph) and life table experiments were carried out in the laboratory. Phloem phase times were significantly longer on Ferrari, Jinju, Debla, and Rapido than Orobell and Thialf. Non-penetration times were conversely observed. Life span, reproduction period, total fecundity, and intrinsic rate of increase (r<, SUB>, m<, /SUB>, ) of M. persicae, were higher on Ferrari, Debla, Orange glory, and Jinju than on Purple, GreenAce, Orobell, and Thialf. On the bases of these results, we conclude that M. persicae preferred Ferrari, Jinju, Orange glory, and Debla among the 15 tested sweet pepper varieties. However, we could not show the preference of the aphid for Purple, Orobell, and Thialf.

The green peach aphid, Myzus persicae Sulzer, is one of the most important pests affecting protected and open-grown crops, because they cause direct damage by feeding on crops and indirect damage as virus vectors. It has recently become a serious problem because of the continuous use of insecticide resulting in resistance among green peach aphid population. Thus, the development of entomopathogenic fungi as aphid biocontrol agents has received increasing interest as part of integrated control strategies. In this study, we report the screening result of pathogenic fungi for the control of green peach aphid. Initial screenings were performed using 347 isolates of putative pathogenic fungi from Korea soils. As results, 20 isolates of entomopathogenic fungi were isolated from cadavers of green peach aphid supporting fungal conidiation. These isolates were identified as three strains of Lecanicillium attenuatum, nine strains of Beauveria bassiana, one strain of Metarhizium anisopliae, one strain of Metarhizium flavoviride, five strains of Paecilomyces lilacinus, one strain of Aspergillus sp. by microscopic examination, genetic sequencing of the ITS region and Universally Primed PCR (UP-PCR). Based on the screening results, twenty isolates were tested for their pathogenicity against adult green peach aphid. All fungal isolates were pathogenic to green peach aphid but mortality varied with isolates. These entomopathogenic fungi may be useful to develop eco-friendly insecticide to control green peach aphid.

The green peach aphid (Myzus persicae) is a cosmopolitan pest of agricultural and horticultural crops and causes serious economic damages. M. persica has rapidly developed resistance to a wide variety of insecticides, including pyrethroids. Target site insensitivity mechanism mediated by two mutations (L1014F and M918T) on the para-type voltage-sensitive sodium channel (vssc) is mainly responsible for pyrethroid resistance. To predict the vssc resistance allele frequency, quantitative sequencing (QS) protocol was established. Frequency prediction equations generated from the plots of signal ratios and amplification critical time showed a high correlation coefficient (r2>0.993), indicating its high accuracy in prediction. QS results revealed that the kdr-type L1014F mutation is only present in Pyeongchang strain. No field strains of M. persicae possessed the super-kdr type M918T mutation. However, a novel M918L mutation was found by genotyping approach. The allele frequencies of M918L and L1014F were 0% to 53% in populations examined, and the level of M918L mutation frequency was closely related with pyrethroid resistance. Therefore, QS-based detection of M918L mutation frequency should faciltate the monitoring of pyrethroid resistance in the field.

The green peach aphid (Myzus persicae) is a serious pest of agricultural and horticultural crops all over the world. M. persica has rapidly developed resistance to a wide variety of insecticides, including carbamates. The E4/FE4 carboxylesterase is known to be involved in carbamate resistance. To compare the E4/FE4 carboxylesterase gene copy number, as a genetic resistance marker, between seven field strains, quantitative real-time PCR (qPCR) was performed. In addition, quantitative sequencing (QS) was employed to predict the frequencies of acetylcholinesterase (AChE) mutations (A301S and S431F) that are associated with target site insensitivity. All M. persica strains examined possessed the S431F mutation in the heterozygous state except for a susceptible strain, implying the possibility of AChE duplication. In contrast, no A301S mutation was found. Frequency prediction equation was generated from the plots of signal ratios and amplification critical time, which showed a high correlation (r2>0.996). QS analysis of M. persicae populations revealed that the allele frequency of S431F ranged 4% to 63%. Taken together, the AChE resistance allele frequencies determined by QS and the E4/FE4 gene copy number by qPCR should facilitate the detection and monitoring of carbamate resistance in M. persicae in the field.

The green peach aphid, Myzus persicae (Sulzer), is one of the most important insect pests in the world. We have explored the possibility of using sounds as a stressor to control this species. Five sine wave frequencies (100, 500, 1000, 5000, 10000 Hz) with combination of three intensity (66, 78, 90 dB) were used as acoustic stimuli in the playback experiments. For behavioral bioassay, we examined frequencies of honeydew production (HDP) and wagging behavior, and duration of moving behavior. The HDP occurs regularly during each stage of nymphal or mature period, and rate of the HDP indicates a degree of food consumption. Aphids conduct wagging to determine a host plant or to find a feeding site. The moving behavior may be regarded as dispersal. As results, all acoustic stimuli significantly reduced rate of the HDP and increased rate of the moving behavior. There was a significant effect to induce the moving behavior in the test of 5000 Hz. In addition, the acoustic stimuli using 5000 Hz were the most effective to disturb feeding behavior of M. persicae at an individual level.

Aphids feed on host plants by penetrating the stems or leaves with stylets. The feeding behavior of aphids consists of probing, penetration, salivation, and sap ingestion. To assess the effects of sound on feeding behavior, we monitored the stylet activity of the green peach aphid, Myzus persicae (Sulzer), using electrical penetration graph (EPG). The use of EPG was critical for determining the stage, frequency, and duration of feeding in aphids. We played back four acoustic stimuli of sine waves with frequencies of 100, 500, 1000, and 5000 Hz to adult aphids. When the sound was treated, the frequencies of probing, penetration, and salivation increased, whereas the duration of sap ingestion decreased. The 100 Hz and 500 Hz was significantly effective to disturb ingestion of phloem sap. The results of EPG revealed that the acoustic stimuli may restrict aphid feeding by disturbing sap ingestion.

This study was performed to investigate the effect of flonicamid and thiamethoxam treated at sublethal concentration (LC10, LC30) on development period, adult longevity and fecundity and the feeding behaviour of Myzus persicae adult. Developmental period of M. Persicae nymph took 5.9 days in LC10, and 6.1 days in LC30 in both insecticides, comparing with control (5.7 days), it showed longer than those of the control, but there was no significance. Adult longevity treated at LC10 and LC30 of flonicamid was showed 13.2 and 13.7 days, respectively, and LC10 of thiamethoxam was examined as 14.7 days, it showed longer than control of 11.6 days. Mean daily fecundity exhibited higher in LC10 (3.1) and LC30 (3.1) of flonicamid than that of control (2.5), but thiamethoxam are not. Total fecundity exhibited higher in LC10 (41.8) and LC30 (43.0) of flonicamid, in LC10 (42.1) of thiamethoxam than that of control (29.5). Feeding behavior was examined using EPG (electrical penetration graph). EPG data indicated that flonicamid and thiamethoxam increased the duration of non-probing periods and decreased the duration of phloem ingestion.

Pyrifluquinazon은 새로운 생물학적 활성 모형을 기초로 만들어진 화학합성 살 충제이다. 이 살충제의 작용기작은 곤충의 행동을 변형시켜 섭식을 하지 못하게 함으로서 굶어 죽게 하는 것으로 알려져 있다. 본 실험에서는 pyrifulquinazon의 완효형 제형을 만들어 복숭아혹진딧물에 대한 섭식행동과 살충효과를 검증하였 다. pyrifluquinazon nano type은 코팅할 때 사용되는 키토산 용액의 분자량과 농 도에 따라 CS 30,000 0.1%, CS 3,000 0.3%로 제조하여 완효형 제형으로 사용하 였고 원제형태의 pyrifluquinazon을 대조구로 사용하였다. 또한, EPG를 이용하여 이 약제에 대한 생물검정과 섭식행동 결과를 비교하였다. CS 30,000 0.1%를 추천 농도(50ppm)로 처리했을 때 진딧물 살충효과와 증가율은 약제 처리 초기에는 저 조하였지만 6일 후부터 점차 증가하였고, 처리 8일 후에 살충율이 가장 높았다. CS 3,000 0.3%의 경우, 처리 18일 후에 살충율이 71.7%를 나타냈고, 증가율은 -0.43 으로 효과적인 완효형 제형의 결과를 보였다. 또한, 두 가지 nano type을 각각의 농 도(25, 50, 100ppm)로 처리함에 따라, 복숭아혹진딧물에 대한 완효형 제형의 특성 과 살충효과를 관찰한 결과, CS 30,000 0.1% 타입의 생물검정 결과, 다른 농도에 서 보다 100ppm으로 처리한 경우 약제 처리 후 모든 일차에서 가장 효과적으로 증 가율 저해가 관찰되었고, CS 3,000 0.3%를 100ppm으로 처리한 경우 약제 처리 18일 후에 살충율이 68.3%로 가장 높았다. 25, 50ppm의 농도로 희석된 2가지 nano 타입과 원제 형태의 제형에 대한 복숭아혹진딧물의 생물검정과 섭식행동을 비교하기 위해서 EPG를 수행한 결과, 25, 50ppm 모두 원제 형태의 제형의 경우 섭식 억제 효과가 약제 처리 2일 후에 가장 좋았지만, CS 30,000 0.1%는 25ppm에 서 처리 8일 후, 50ppm에서 처리 14일 후, CS 3,000 0.3%의 경우 25ppm에서 처 리 28일 후, 50ppm에서 처리 14일 후에 섭식억제 효과가 가장 우수하였다. 또한, 25ppm의 CS 3,000 0.3%에서 처리 12일부터 30일 까지, 50ppm에서는 처리 14일 부터 30일까지 reaction time이 관찰되어 CS 3,000 0.3%가 가장 효과적인 완효형 제형의 특징을 나타내었다.

파프리카를 가해하는 복숭아혹진딧물의 국내 전남지역의 수출농가에서 많이 재배되고 있는 파프리카 품종에 대한 기주 선호성을 조사하였다. 파프리카 15품종 을 선발하여 각각의 EPG 패턴을 관찰함으로써 복숭아혹진딧물의 섭식행동을 알 아보고 생명표작성 조사를 통하여 생태학적 측면을 관찰함으로서 품종간 기주 선 호성을 비교연구하였다. 복숭아혹진딧물이 각 품종에서체관부 섭식시간은 Orobell과 Thialf 품종에서 짧은 시간동안 이루어졌고, Ferrari, Jinju, Rapido 품종 에서 흡즙하는 시간이 길었다. 또한 구침을 빼고 섭식하지 않는 시간은 Ferrari, Jinju, Rapido 품종에서 짧게 나타났고, Orobell, Thialf 품종에서 길게 나타났다. 생명표를 비교하여 보면, 총 산자수와 내적자연증가율(rm)은 Coletti, Mazzona, Rapido, Scirocoo 품종에서 낮았고 Debla, Ferrari, Orange Glory, Jinju 품종에서 높았다. 총 산자수와 내적자연증가율(rm)은 체관부 섭식시간과 비례하여 나타나 지는 않았다. EPG 패턴분석과 생명표를 분석하여 종합한 결과를 미루어 추측하면 복숭아혹진딧물이 선호하는 품종은 Ferrari, Jinju, Orange Glory 품종 등이었고, Orobell, Purple, Thialf 품종 등은 다른 품종에 비하여 덜 선호하였다.

The green peach aphid(Myzus persicae) and sweet-potato whitefly(Bemisia tabaci) biotype Q are serious pests in hot pepper and cucumber. To optimize the formulation type of Clothianidin 1.8% granule, coated and extruded granule formulation types were tested against green peach aphid in hot pepper and sweetpotato whitefly in cucumber. Clothianidin 1.8% granules were incorporated in soil before transplant of hot pepper and cucumber. At recommend dose(540g ai/ha), the efficacy of Clothianidin 1.8% coated and extruded granules were 83.3% and 94.4% and continued until 50 days and 70 days against green peach aphid, respectively. Against sweet-potato whitefly, the efficacy of Clothianidin 1.8% coated and extruded granules were 65.7% and 96.3% at 32 days in cucumber, respectively. Clothianidin 1.8% extruded granule was safe on crops (hot pepper, cucumber, melon, cabbage etc.) at 540g ai/ha (recommend dose) and 1080g ai/ha. The results suggested that Clothianidin 1.8% extruded granule is promising as a best insecticide against green peach aphid and sweet-potato whitefly, because of the high efficacy and low phytotoxicity.

In this study, we compared global proteome profiles and the expression pattern of defense-related genes in Chinese cabbage when infested by Myzus persicae and Plutella xylostella. Four-week-old Chinese cabbage was exposed to each insect for 24 h, and then proteins and total RNA were extracted from leaves. To elucidate the herbivore-induced differentially expressed proteins in Chinese cabbage, proteins were separated by two-dimensional gel electrophoresis, and visualized by staining with Coomassie G250. Approximately 1600 protein spots were separated and 249 protein spots showed reproducible changes in expression. Among them, nine proteins whose expressions were markedly up-regulated in M. persicae-infested group were identified using matrixassisted laser desorption/ionization time of flight mass spectrometry. The identified herbivore-responsive proteins (ribulose-1,5-bisphosphate carboxylase/ oxygenase, ATP synthase CF1, putative mismatch binding protein Mus3, and integrase core domain-containing protein) were involved in regulation of photosynthesis, carbohydrate metabolism and DNA repair. The expression levels of chitinase, b-1,3-glucanse, peroxidase, PR1, and PR4 in herbivore-infested Chinese cabbage were analyzed by reverse transcription-polymerase chain reaction. The results clarify the response of Chinese cabbage to two herbivore attack at the protein level.

The possibility of commercializing the controlled release of chitosan carrier nano formulation was examined with mortalities and population increase rates of Aphis gossypii and Myzus persicae after treatment of 2 α-cypermethrin nano type formulations of different chitosan carrier molecular weight (M.W. 3,000 and 30,000) and 2 etofenprox nano types of chitosan content (70% and 80%). After 14 days of treatment, α-cypermethrin nano formulation showed over 40% mortality against A. gossypii. Therefore, it was confirmed that the insecticide release was controlled through chitosan carrier. Results of the investigation of insecticidal activity of α-cypermethrin nano formulation showed there were no differences between nano types at 4 days after treatment. However, after 14 days, the population increase rate treated with chitosan M.W. 30,000 formulation was -0.037, much lower than that of M.W. 3,000 formulation with 0.231. The result exhibits that chitosan M.W. 30,000 formulation would be a suitable controlled release formulation. On the other hand, etofenprox formulations didn’t show any significant insecticidal effect or persistency difference against both aphid species.

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.