Six plant essential oils, vanillin, and their mixtures were tested for repellent activities and olfactory responses in a dengue virus vector mosquito, Aedes aegypti. Among the plant essential oils, cassia oil showed complete protection time (CPT) of 75 minutes. CPTs of lemongrass, lemoneucalyptus, xanthoxylum oils, and vanillin were within 30 minutes at 5% (0.21 mg/cm2) tested level, although their CPTs were not comparable to same concentration of DEET that showed 127.5 minutes of CPT. However, their repellency effects were significantly improved in two conditions; improving concentration up to 15% level (0.63 mg/cm2) and addition of vanillin. In bioassays using binary or tertiary mixtures with one or two essential oils with or without vanillin, the composition of 1:3:1 (v/v/w) consisted of lemongrass oil, xanthoxylum oil and vanillin provided 270 min-CPT. As a practical application, the mixture of 1:1:1 formulation containing lemongrass oil, xanthoxylum oil, and vanillin (v/v/w) was enclosed into the Viscopearl, porous cellulose beads that provide gradual release of volatile compounds. Efficiently, more than 90% of repellency for 2 hours was observed in cage and semi-field chamber tests using the formulation. In addition to behavioral assays, we subsequently examined how mosquitoes sense the blends of oils with vanillin by using electroantennogram (EAG) recording. Binary mixture with one oil and vanillin, which extended CPTs, showed no significant patterns of EAG alternation, while tertiary mixtures of oils and vanillin decreased patterns of EAG responses as an increase of vanillin contents in the mixture, implying further potential roles of vanillin as a synergist in mosquito repellency. Based on behavioral and electrophysiological data, cassia, rosemary, lemongrass, xanthoxylum, and lemoneucalyptus oils could provide the high possibility for development of commercial products for useful management strategies to control mosquitoes.

Alzheimer’s disease (AD) is a fatal disorder wherein patients suffer from sensory, motor, and cognitive loss. Currently, the identification and validation of biomarkers for diagnosing AD and other forms of dementia are increasingly important. Olfactory dysfunction is present in patients diagnosed with Alzheimer’s disease or idiopathic Parkinson's disease. Alzheimer’s patients show neuropathological changes in areas of the brain central to the olfactory processing center, suggesting the theoretical importance and potential diagnostic utility of investigating functional changes in olfaction in these patients. However, the usefulness of olfactory screens to serve as informative indicators of Alzheimer’s is precluded by the lack of knowledge regarding neural and molecular mechanisms underlying olfactory dysfunction onto Alzheimer's diseases. To test these ultimate questions, we used molecular and electrophysiological recording techniques to find out the difference of olfactory responses and AD related protein expression patterns by using fly model, Drosophila melanogaster that over-expresses the human β -amyloid, tau protein. We postulated that such flies would present with progressive olfactory impairments compared with age-matched wild type control flies. In this study, our hypothesis is that there is a correlation between olfactory deficits and the spatial expression pattern of β-amyloid and tau protein deposition. Therefore, we demonstrate a specific concentration of lesions in central olfactory structures such as antenna and Maxillary palps. Our study indicates that deficits on olfactory identification may occur in AD, which will be valuable as an indicator of neuropathogenesis.

Cinnamaldehyde as the main component of Cinnamomum plants is well known as mammalian transient receptor potential ankyrin 1 (TRPA1) agonist, also activated by low temperature stimuli and mechanosensation. The other TRP subfamily, transient receptor potential vanilloid-1 (TRPV1) sensitive to pungent compounds such as capsaicin and allicin mediates the feeling of warmth. Both TRPA1 and TRPV1 channels are abundantly distributed in sensory neurons. Thus, there is possibility that these channels modulate repellent behaviors of mosquitoes and Drosophila through olfactory receptor neurons (ORNs). In order to confirm this hypothesis, we carried out laboratory repellent tests with cinnamaldehyde to Aedes aegypti females using arm-in-cage test and to a wild type and two TRP channel mutants Drosophila lines using a choice assay. Cinnamaldehyde showed strong repellency against Ae. aegypti and Drosophila wild adults at tested concentrations. However, a mutant fly line did not discriminate or detect the existence of the repellent. These behavioral data suggest that cinnamaldehyde may directly target the TRP channel. More studies to elucidate neural correlates of repellency to ainnamaldehyde compound are as follows: 1) Identifying the ORNs mediating cinnamaldehyde detection using single-sensillum recording techniques, 2) Co-localization of TRP genes on olfactory organs of Ae. aegypti and Drosophila using in situ hybridization and 3) Whether the Aedes TRP homologs might function in cinnamaldehyde repellency using rescued TRP chennels of Drosophila.

The subfamily Acaenitinae Foerster, 1869 is a small-sized group belonging to the family Ichneumonidae. It includes 250 species in 26 genera from Ethiopian, Oriental, and Palaearctic region. However, only 14 species of six genera, Arotes, Coleocentrus, Jezarotes, Phaenolobus, Spilopteron and Yamatarotes have been reported from Korea. This subfamily can be easily recognized from other ichneumonids by the combination of the following characters: subgenital plate very elongate; tarsal claws with accessory tooth. Members of Acaenitinae are parasitoids of wood-boring Coleoptera, Hymenoptera and Lepidoptera. Among them, some of parasitoids of Cerambycidae are known as intermediate carrier of Bursaphelenchus xylophilus (Nematoda: Parasitaphelenchidae). In this study of the Korean Acaenitinae, we found the genus Yezoceryx from Korea for the first time, including newly recorded two species, Y. sp.1 and Y. sp.2. We provide description of the genus and two species with a key to the Korean genera of the subfamily Acaenitinae.

Aedes aegypti is a primary vector that transmits dengue and yellow fever around the world. To prevent the spreading and elimination of mosquitoes, insecticides and repellents like DEET (N, N-diethyl-m-methyl benzamide) have been broadly used. Even though DEET is considered as highly effective and proven protection against mosquito, it causes skin irritants and rashes, melts some synthetic plastics, and unpleasant smells. Therefore, there is a trend finding alternative mosquito repellents instead of using DEET. We tested repellent effects with plant essential oils and synergistic effects of those plant essential oils with additional vanillin, comparing them to DEET itself. Some of prepared mixtures showed better repellency than DEET. In addition, we evaluated the differences in the peripheral olfactory responses of Ae.aegypti females using EAG tests (electroantennogram). The aim of this test is to determined how the vanillin within plant essential oils or DEET acts in mosquito’s olfactory organs in aspect of molecular mechanisms. Revealing the novel function and localization of these putative repellent receptors may provide new insight into development of repellent as well as behavioral control agents in the future and contribute to understand the mechanism of processing patterns of repellent receptors in mosquitoes.

The genus Gonioctena Chevrolat is distributed in the Holarctic and Oriental regions, with more than 80 species. Many species of the genus have great similarity in external morphology and coloration, often cause misidentifications. Thus, the shape of the aedeagus is mainly used to distinguish closely related species. Fifty-four species, more than half of the known taxa, occur in northeastern Asia, including 18 species in the Russian Far East, 29 in China, 11 in Korea, and 18 in Japan. Among these, G. gracilicornis Kraatz (type locality: Amur) is widely distributed in Russia, China, Mongolia and Korea. However, extensive investigation on Gonioctena in Korea revealed that the Korean population of G. gracilicornis differs from that of the Russian by the coloration, the puncturation of pronotum, and the shape of aedeagus. The purpose of this study is to describe a new species of Gonioctena that was previously misidentified as G. gracilicornis. A key to Korean Gonioctena, distribution, and host plant are also provided.

Although many synthetic pesticides have played important roles in pest management in agriculture, forest, housings, gardens, and managed landscapes for several decades, increased concerns to human health and environmental contamination have limited their usages and application in integrated pest management (IPM). Many plant essential oils have a variety of biological activities including adulticidal, acaricidal, larvicidal, ovicidal, repellent, antifeedant, and oviposition deterrent ones against insect pests. These oils and major terpenoid constituents show neurotoxic effects by interference with the cockroach octopamine and nematode SER-2 tyramine receptors. Most plant volatile oils contain plentiful phenylpropanoids, mono and sequiterpenes, and related phenols. They have been widely used in the flavor, fragrance, aroma therapy, food additives, and cosmetic industries. Some volatile plant essential oils have traditionally been used as stored product protectors and mosquito repellents, while their successful cases in commerce have been recently applied. Especially, these essential oils have not only been treated against house and garden pests, but these oils also have higher potential to be employed as “green pesticides” in the field of stored products, green house, and medical insect pests due to their fumigant action. Eventually, considering resistance development to many synthetic pesticides, it is likely that plant volatile or essential oil-based pesticides would play an essential role as an alternatives since they typically consist of the complex mixtures of constituents responsible for slow resistant development. In addition, the mixtures of these oils with conventional insecticides and the application of their capability to to enhance the efficacy of conventional products remains a main market niche. In this presentation, several cases of test evidences under laboratory and field conditions will be discussed. Ultimately, plant volatile-based pesticides and repellents would play an important role in future IPM programs due to their relative safety to non-target organisms and the environment.

Electroantennogram techniques (EAGs) were employed to record olfactory responses in the antennae of the adult female stable fly, Stomoxys calcitrans (Diptera: Muscidae), to Zanthoxylum piperitum pericarp steam distillate (ZP-SD), Z. armatum seed oil (ZA-SO) and their 29 volatile constituents alone as well as binary mixture of the ZP-SD and ZA-SO with 1-octen-3-ol. The electrophysiological responses of the test materials were compared with those of DEET and 1-octen-3-ol. At concentration of 10-1 (v/v) in mineral oil, ZP-SD, ZA-SO, and all volatiles elicited EAG responses in the fly antennae except for DEET, which is extremely low volatile. ZP-SD, ZA-SO, and some of the test volatiles elicited EAG responses rather lower than 1-octen-3-ol, which showed vapor phase repellency and toxicity to the fly in our previous behavioral research. This suggests that the stable fly possesses olfactory receptor neurons responding to given repellent compounds per se. In binary mixture with 1-octen-3-ol at concentration of 10-1, ZP-SD and ZA-SO elicited 16±0.55 and 18±0.63 mV while ZP-SD, ZA-SO, and 1-octen-3-ol alone elicited responses of 14±0.45, 15.8±0.37 and 16.2±0.58 mV, respectively. Among the volatile compounds, terpinen- 4-ol, β-myrcene, α-phellanderene, citronellal, and limonene oxide elicited 80 – 96% relative EAG amplitude compared to 1-octen-3-ol as a reference (100%). Based on structure-activity relationships, constituents having aldehyde moiety elicited bigger EAG responses than those of alcohol or ether one. The perception in the fly antenna to plant volatile compounds exhibited complicated patterns of olfactory responses. Current and future directions of this study on sensory processing mechanisms underlying repellent behaviors will be discussed.

The perilla leaf pyralid moth, Pyrausta panopealis Walker (Lepidoptera: Pyralidae), is a serious pest damaging to leaf perilla. In order to establish the life parameters of P. panopealis for eventual purpose of control, the developmental span of each stage were investigated under five temperature regimes (20℃ ~ 3 0℃). In addition, the larvicial efficacy of several on-the-market environment-friendly agricultural materials (EFAMs) was tested. The width of head capsule at each larval stage measured to be the mean of 0.21, 0.32, 0.47, 0.64, and 0.98 mm, respectively. The larval period of P. panopealis was longest at 20ºC as 27.0 days and shortened as temperature goes up to 30ºC as 11.3 days. Survivorship of the larval P. panopealis was the highest at 30ºC as 80%, whereas that of other temperatures ranged from 40% (20ºC) to 62.5% (27.5ºC), indicating that the P. panopealis appears to favor higher temperature. In addition to larval period, the duration of egg, prepupa, and pupa stages also shortened as temperature goes up, whereas the duration of adult stage increased as temperature goes up: from 4.1 days at 20 ºC to 6.1 days at 30ºC. After the perilla leaf pyralid moths were successfully stabilized in indoor environment the larvicidal efficacy of the ten EFAMs that were previously selected from the result of other moth species was tested aimed at 4th instar larvae for 48 hrs. Seven of the ten tested showed more than 90% of mortality within 12 hrs and reached nearly up to 100% within 24 hrs, but the remaining three showed less than ~70%.

The subfamily Acaenitinae Föster, 1869 is a small-sized subfamily belonging to the family Ichneumonidae. Members of Acaenitinae distributes in Ethiopian, Oriental, and Palearctic Regions. Twenty six genera have been recorded in the World, and six genera are known from Korea. The biology of the Acaenitinae is not well known, however, some hosts are recorded from Cerambycidae in Coleoptera (Gardiner, 1960), Sesiidae and Tortricidae in Lepidoptera (Ulbricht, 1909; Starke, 1956). Generally female is easily distinguished from that of other subfamily of Ichneumonidae. They can be recognized by their very elongate subgenital plate, and by the auxiliary tooth on the tarsal claws. Male can be also easily recognized by the form of the claws and the facial shape. In this study, we found a newly recorded genus Yezoceryx, belonging to the Tribe Acaenitini, with two species in Korean fauna. Illustrated key of species and genera, diagnosis and photographs of each species are provieded.

The vapor phase repellency and toxicity of Zanthoxylum piperitum pericarp steam distillate (ZP-SD), Z. armatum seed oil (ZA-SO), and their 29 constituents to the adult female stable fly, Stomoxys calcitrans (Diptera: Muscidae), were examined using filter paper fumigation bioassay. Results were compared with those of the currently used repellent: DEET. Both of ZP-SD and ZA-SO exhibited vapor phase repellency and toxicity to female flies at 5 to 40 mg/filter paper (0.23 to 1.82 mg/cm3 air) during a 120-min exposure, whereas DEET exhibited neither repellency nor toxicity to the stable fly. At 5 mg/filter paper, vapor phase of ZP-SD and ZA-SO repelled 50 to 67% and 61 to 51% flies, respectively, to control area during 30 to 120 min. At 40 mg/filter paper, vapor phase of ZP-SD and ZA-SO caused 100% and 81% mortality, respectively, after 120 min of exposure. Among the tested volatile constituents, cuminaldehyde was the strongest repellent and toxic compound to the fly and was four times more toxic than ZP-SD and ZA-SO. Cuminaldehyde vapor phase repelled 62% flies to control area after 30 min at 2.5 mg/filter paper and caused 100% mortality after 120 min at 10 mg/filter paper. Based on the structure-activity relationships, the toxicity and repellency of constituents having aldehyde moiety were better than those of alcohol or ether one. Overall, ZP-SD, ZA-SO, and their bioactive constituents could be useful as potential vapor repellents to control stable fly population.

To identify DNA markers linked to a elytra polymorphism, amplified fragment length polymorphism (AFLP) analysis was performed on DNA samples from four each colour pattern individuals (2 females and males), for example, succinea 1, succinea 2, conspicua, and spectabilis. As a result of performing AFLP analysis with the restriction endonuclease combination EcoRⅠ and Mse I, total of 2,269 AFLP fragments which were specific to succinea, conspicua and spectabilis was identified using 24 different AFLP primer combinations. Among these 2,269 fragments, 16 bands which were the most specific to one color patterns were isolated, cloned and sequenced. Subsequent UPGMA cluster analysis revealed that population of H. axyridis was divided four major group and these genetic tree showed that H. axyridis elytra colour diversity was affected by genetic polymorphism. It is considered that these genetic analyses may be facilitated the understanding of molecular genetic mechanism related with the wing colour pattern formation in this species.