The mitochondrial COI gene has proven successful for identifying the lepidopteran species. In addition, this gene has been applied to recognize cryptic species and confirm a polyphagous species as one species. However, it has been also reported misidentification in the COI gene. As a result, some researchers have suggested the use of additional genes in species identification, especially, nuclear genes. In this study, we observed that a nuclear EF1agene is better than the mitochondrial COI gene in recognizing Stathmopoda species. For example, among the all species, 47 individuals of nine species, a large intraspecific pairwise difference were detected, up to 15.0% in universal barcoding regions of the COI gene, 22.0% in other part of the COI gene; however, 2.0% in EF1a. In contrast, Stathmopoda sp2 and S. commoda were separated into several clusters in each different COI regions, and some individuals of S. auriferella and S. commoda, were closer to each other separating from the cluster of the same species. But, we get clear results from the EF1a, Stathmopoda species well clustered and could be distinguished.

On Birches (Betula spp.), more than seventy species of aphids in eighteen genera are recorded worldwide, mostly (> 60%) belonging to ten genera of the subfamily Calaphidinae (Hemiptera: Aphididae). In Korea, only seven Birch feeding aphids are recorded. Recently, we recognized two calaphinid species, Calaphis betulaecolens (Fitch, 1851) and Euceraphis betulae (Koch, 1855) as new to the Korean peninsula.

Laos, a landlocked country in Southeast Asia, has most extensive network of ecosystems in the Indochina Peninsula, surrounded by Myanmar and China to the northwest, Vietnam to the east, Cambodia to the south and Thailand to the west. It is the tropical vegetation and warm climatic conditions influenced by monsoon. Such geographical and climatic condition is favorable for the diversity of insects. However, research or educative investigation on insects have been poorly conducted. Through recent expedition during dry season (between December 2012 and February 2013), mainly held at Phou Khao Khouay National Park (PKKNP), which varies from sheer sandstone cliffs and pristine river gorges to rough mountain slopes along the Mekong river, we recognized atotal of 88 lepidopteran insects belonging to 22 families, Arctidae, Attevidae, Choreutidae, Cossidae, Crambidae, Geometridae, Gracillariidae, Hesperidae, Hyblaeidae, Limacodidae, Lycaenidae, Lymantridae, Noctuidae, Nymphalidae, Oecophoridae, Papilionidae, Pieridae, Pyralidae, Scythrididae, Sphingidae, Uraniidae and Zygaenidae, were recognized.

The aphid genus Micromyzodium David, 1958 is newly recognized in the Korean peninsula. This genus is characterized by very long dorsal abdominal hairs, almost 3-4 times as long as basal diameter of antennal segment III. Colonies of two Micromyzodium species; Micromyzodium kuwakuse Uye 1924 and Micromyzodium nipponicum Moritsu 1949 were collected on Fatoua villosa Nakai (Urticales: Moraceae) and Perilla frutescens Britton (Lamiales: Lamiaceae), respectively. In this study, we redescribed, illustrated, and measured for apterous viviparous females of the two species.

The exotic aphid pest, pomegranate aphid, Aphis punicae Parsserini, 1863 (Hemiptera: Aphididae), is newly recognized in the Korean peninsula. This species is originally distributed throughout the Mediterranean regions, the Middle East, Ethiopia, India, Pakistan, Indonesia, and Turkey. In the major producers of pomegranate such as India and the Mediterranean regions, this species is regarded as one of the most serious insect pests inflicting injury on pomegranate, Punica granatum Linnaeus. By sucking plant sap and excreting honeydew, aphids cause various plant diseases and virus infections which are more likely to occur as population size increases. Aphis punicae infests together commonly with Aphis gosspii Glover, and rarely with Aphis craccivora Koch and Aphis spiraecola Patch on P. granatum in Korea. In this study, we first compared two closely related species, A. gossypii and A. punicae, based on morphometric analysis to confirm their morphological relationships. Second molecular identification using mitochondrial COI barcode region was performed for the aphid samples collected from P. granatum.

In terms of aphid species identification, both host plant association and morphological characteristics are crucial factors. However, aphids in the genus Aphis Linnaeus (Hemiptera: Aphididae) often are cryptic in morphology due to their rapid radiation. Moreover, overlapping host plant species can make difficult situation worse. Three cryptic species Aphis gossypii Glover, Aphis glycines Matsumura, and Aphis rhamnicola sp. nov. occur together on the Buckthorn, Rhamnus spp. in the overwintering season in Korea. Due to lacking informative morphological characters and host plant sharing, the new species recently has been recognized as a distinct species. In this study, A. rhamnicola sp. nov. on various host plants was compared with the primary host sharing species, A. gossypii and A. glycines, based on morphological and molecular characteristics. In the results, there were significant genetic differences between three species, despite the high similarities in morphology. Our results provide strong evidence for establishing new species, which seems to be a typical heteroecious species that alternates between only primary host, Rhamnus spp., and various secondary hosts. We describe a new species, A. rhamnicola sp. nov., for apterous and alate vivipara, fundatrix, ovipara, and gynopara, including diagnostic key for host sharing species in genus Aphis.

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.

Many polyphagous herbivore insects considered as a single species are indeed comprised of genetically differentiated host related races that utilize several unrelated plant families. Aphis gossypii Glover, one of the extremely polyphagous aphid species, has more than 100 host plants distributed worldwide. In Korea, it takes holocyclic life cycle, with a number of primary hosts, which is unusual for other aphid species. However, former population genetic studies on A. gossypii have dealt with the populations from only a few agricultural host plants. In this study, we hypothesized that different primary host utilization may be restricted for certain host races and this may play a key role of the genetic differentiation in this species. We collected the cotten aphid populations from 36 different host plants, 5 primary and 31 secondary hosts including various wild and non-cultivated plants. To determine population genetic structure, we analyzed genetic differentiation among those populations using 9 microsatellite loci. As results, four genetically distinct clusters were verified. Of the five primary host populations, there were significant gaps in genetic differences between Rhamnus-associated group and Hibiscus-associated group, and the other populations were affinitive with the Hibiscus-associated group. Overall, primary host populations have a higher level of genetic diversity than secondary host populations. Several populations associated with secondary hosts such as spiderwort, madder, and Korean lettuce were considerably differentiated in the result of principle component analysis, which nearly showed the species level difference similar to Aphis glycines Matsumura and Aphis sp. ex Rhamnus. Thus, there could be reproductively isolated by the loss of primary hosts, and might be already speciated from A. gossypii

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.

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 control agent in this species. Sine waves with four different frequencies (100, 500, 1000, 5000 Hz) were used as acoustic stimuli in the playback experiments. As a behavioral bioassay, we recorded honey dew production (HDP), wagging, and walking. HDP occurs regularly at each stage of nymphal and adult periods, and the rate of HDP may indicate a degree of food consumption. Aphids conduct wagging to determine a host plant or to find a feeding site. Walking may be regarded as dispersal. All acoustic stimuli significantly reduced the rates of HDP and increased the rates of wagging. There were no significant effect of acoustic stimuli on walking. Based on the bioassay, the acoustic stimulus with 5000 Hz seemed to be the most effective on inhibiting feeding behavior of this aphid species at an individual level.

Lycorma delicatula (White 1845), which has been recently introduced into Korea, is a notorious pest on grapes. This invasive insect has rapidly spread throughout central and southern Korea. To date, we have no behavioral or population genetics information, such as invasion routes and subsequent dispersal rates in Korea, to help understand and control populations of L. delicatula. Here, we have developed 15 novel microsatellite loci for L. delicatula. The isolated loci were polymorphic, with 2 to 19 alleles in 42 individuals from a single population in Cheonan. The analyses revealed that all 42 individuals had different multilocus genotypes with heterozygosity ranging from 0.214 to 0.866. Eleven of the 15 loci did not deviate significantly from Hardy-Weinberg equilibrium. The isolated markers will facilitate population genetic studies of L. delicatula.

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.

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.