As global warming and consumer’s preference for tropical/subtropical fruits increase, the number of orchards cultivating tropical/subtropical fruits in Korea is increasing. Accordingly, concerns about the introduction of exotic invasive pests that host tropical fruits. In this study, efficacy of ethyl formate(EF), as alternative to methyl bromide(MB), was evaluated. Commercial trial of EF was conducted in mango post-harvest storage conditions for controlling Scirtothrips dorsalis. Application of 10 g/m3 of EF for 4 hours at 10 ℃ showed proven efficacy on S. dorsalis without any phytotoxic damage on mango fruits in that condition.

The two-spotted spider mite, Tetranychus urticae Koch, is one of the most important agricultural pests. Therefore, we screened fifteen compounds from natural products for their spatial repellent and oviposition deterrent activities against T. urticae in the laboratory by using two-choice and no-choice tests. In the bridge two-choice test, nine compounds showed the spatial repellent effects on T. urticae at 20 mg dose, resulting in reduced numbers of eggs. Among the nine compounds, at 2 mg dose, two compounds were selected as having more spatial repellent activity than the others. The two compounds also showed spatial repellent and oviposition deterrent effects in the two-choice test from hosts. In the no-choice test from a host, the spatial repellent effects of the two compounds to T. urticae were significantly stronger than that of controls. These results suggest that the findings can be used as potential agents for the prevention and population control of T. urticae in the field.

The cotton aphid, Aphis gossypii glover (Hemiptera: Aphididae), is the world-wide agriculture pest and has the ability to become resistant to many pesticides. Hence, we conducted behavioral tests on apterous and alate aphids for series compounds from natural products by using a two-choice test, a no-choice test, a host choice test and electroantennography (EAG). As a result, we found 3 out of 30 compounds for apterous aphids and 2 out of 15 compounds for alate aphids, both of which showed powerful repellent effects on these aphids. In this study, we suggest that our findings could be useful and eco-friendly spatial repellents for controlling cotton aphid.

Fumigation of fruits and vegetables during quarantine and pre-shipment (QPS) treatment should be effective with a shorter fumigation time to minimize phytotoxicity. In this research study, a shorter fumigation time, 2 hours exposure which is shorter than that of the current commercial fumigation procedures using a lower dose of ethyl formate (EF) mixed with phosphine (PH3) on strawberry was investigated. The reciprocal effect between EF and PH3 against nymphs and adult Myzus persicae (Sulzer) and Tetranychus urticae (Koch) was evaluated. In addition, L(Ct)50 and L(Ct)99 of EF only and EF mixed with PH3 were analyzed at 5°C and 20°C. The synergistic ratio (SR) of L(Ct)50 and L(Ct)99 for the nymph and adult stages of M. persicae were >1.0, which indicated a synergistic effect between EF and PH3. However, the SR values of L(Ct)50 and L(Ct)99 of the nymph and adult stages of T. urticae were ≤1.0 indicating that there was no synergistic effect between the two fumigants against T. urticae. Our results showed that the reciprocal effect between EF and PH3 has different effects on M. persicae and T. urticae. This could be attributed to the biological and physical differences between the class Arachnida and Insecta. The synergistic effect between EF and PH3 against M. persicae within a shorter exposure period and without phytotoxicity on fruits and vegetables will significantly benefit the horticultural industry.

페로몬에 기반한 해충방제 기술은 페로몬이 동정되는 곤충의 수가 지수적으로 증가함에 따라 더욱 성공가능성이 높은 전략이 되고 있다. 이 연구는 애기유리나방, [Synanthedon tenuis (Butler) (Lepidoptera: Sesiidae)]의 성페로몬((Z, Z )-3, 13-octadecadien-1-ol.)에 의한 화학 통신교란(pheromone-mediated chemical communication disruption, PCD)의 효과에 대한 것이다. 본 PCD법은 우리나라 전남 순천과 경 남 진주의 2곳의 단감 과수원에서 2016년과 2017년에 총 4회 수행되었으며, PCD의 효과는 성페로몬 처리구와 무처리구에서의 평가용 트랩 포 획수로 나타내었다. 성페로몬 처리구의 평가용 트랩에 유인된 수컷 성충수는 무처리구에 유인된 수보다 유의하게 적었으며, 유인수 감소효과는 95.2~100% (평균 98.8±1.2%)이었다. 이러한 결과로 볼 때 성페로몬에 기반한 애기유리나방의 방제가 가능할 것으로 판단된다

Morphology of antennal sensilla and their distribution were investigated in male and female adults of Gymnosoma rotundatum, a parasitic fly to hemipteran species, using scanning electron microscopy. The overall length of antenna was not different between male and female. Antenna of G. rotundatum was composed of scape, pedicel and funiculus in both sexes. Three types of sensilla (sensillum basiconica, s. chaetica and s. coeloconica) were identified from both sexes, in varying numbers and distribution along the antennae. The two sensillum types were further divided into different subtypes; s. basiconica into three subtypes and s. chaetica into two subtypes. Among sensilla, s. basiconica subtype 1, 2 and 3 were multiporous, indicating that the ir primary function is olfactory, and others were not. The s. basiconica was most numerous on the antennae in both sexes. The number of subtype 1 of s. basiconica was different between male and female. The morphological information obtained in our study provides a basis for electrophysiological and behavioral studies of the olfactory sensory function of each morphological type of sensilla. (Supported by PJ011756022018, RDA)

Spotted wing drosophila (SWD), Drosophila suzukii, is a serious pest of berry fruits and grapes in East-Asia and USA. SWD female oviposits eggs into the skin of ripening fruits, and the larvae dig a burrow inside the fruits. Secondary infestation by other insects and pathogens to the oviposition spots cause substantial economic damages worldwide. SWD has recently been spreading to Europe and USA, and it is becoming a global threat in terms of biosecurity. A quite useful paper has been published in Journal of Chemical Ecology in the most recent issue (Vol. 44, #10) which is titled ‘Advances in the chemical ecology of the spotted wing drosophila (Drosophila suzukii) and its applications’ written by Cloona et al. This article introduces chemical constituents from many odor sources such as fermentation, yeast, fruit, and leaf sources, and commercial lures and traps developed using these compounds. Authors said that the current food-based lures and trap technologies are not expected to be specific to SWD and thus capture large numbers of non-target drosophilids. Attractive and aversive compounds are being evaluated for monitoring, mass trapping, and for the development of attract-and-kill and push-pull techniques to manage SWD populations. (Supported by PJ011756022018, RDA)

Stathmooda masinissa is one of the most serious lepidopteran pests which damaging the furit of persimmon. Its pheromone composition has been idetified as (E4,Z6)-4,6-hexadecadienyl acetate (E4,Z6-16Ac) and (E4,Z6)-4,6-hexadecadien-1-ol (E4,Z6-16OH). We evaluated electrophysiological response of (E4,Z6)-4,6-hexadecadienal (E4,Z6-16Ald) and attractivenss of E4,Z6-16Ald by combination of two pheromone components. E4,Z6-16Ald evolked electrophysiological responses as same to that of two pheromones. The lure combined with E4,Z6-16Ald and two pheromone components attracted more male S. masiissa.

애기유리나방의 성페로몬인 Z,Z-3,13-octadecadien-1-ol (Z3,Z13-18:OH)을 이용한 교미교란 효과를 검증하기 위하여 경남(진주)과 전남(순천)의 단감원에서 2016년부터 2년간 실험을 하였다. 2016년에는 순천과 진주A, 진주B의 세 단감원에 성페로몬 5 ㎎/septum을 각 나무마다 한 개씩 처리하여 교미교란 효과를 확인하였다. 그 결과, 순천과 진주A 과수원에서는 100 %의 교미교란 효과를 나타내었지만 진주B 과수원에서는 효과가 전혀 없었다. 2015년과 2016년 같은 기간에 애기유리나방의 밀도를 조사 결과 진주A 과수원에 비해 진주B 과수원의 애기유리나방 밀도가 약 6.7배 많은 것을 확인 할 수 있었다. 그리하여 2017년 제1화기 때에 진주B 과수원에서 성페로몬 량을 10 ㎎/septum로 늘려서 실험한 결과 교미교란 효과가 66.7%로 낮았다. 2017 2화기 때에 다시 진주A 과수원으로 장소를 옮겨 실험한 결과 100 %의 교미교란 효과가 있는 것을 확인하였다. 이러한 결과로 보아 교미교란 효과는 페로몬 량 뿐 아니라 지형의 영향도 받는 것으로 판단된다.

Azuki bean beetle (ABB), Callosobruchus chinensis (L.) is a field-to-storage pest of legumes and its female produces sex pheromone with two isomeric components, 2Z-homofarnesal and 2E-homofarnesal. Two day old virgin adults were exposed to 0, 200, 300, 400, 500 & 600 Gy gamma radiation and effect on longevity, fecundity, sterility and pheromone production were studied. Longevity (female; P < 0.001, male; P < 0.001) and fecundity (P < 0.001) were dose-dependently affected by the gamma irradiation. Both adults were totally sterilized by the tested doses of gamma irradiation as depicted by the null hatchability of laid eggs. Gas chromatography-mass spectrometry for solid phase micro extraction revealed that both of the pheromone components were significantly but not completely reduced by 300 Gy. It is a pre-requisite for a successful sterile insect technology that the sterility of ABB is induced without the total disruption of calling behavior.

Azuki bean beetle (ABB), Callosobruchus chinensis (L.) is a field-to-storage pest of legumes. It is ideal to estimate its field population before it invades the stored legume stuffs. The seasonal occurrence was monitored with rocket traps supplied with synthetic female sex pheromone and with sweep netting during 2015-2016. Harvest damage was evaluated by taking purposive samples of the pods at harvest. Over-wintering stage was identified from the pod samples of left over plants. The results ascertained that October was the peak season of ABB in the azuki bean field. Grain damage and weight loss of the harvested azuki bean were 2.7% and 2.4% respectively, which could be the inoculum for storage loss. The adult emergence only from live pupae collected from pods revealed for its most probable over-wintering stage. In all, this study provides insight into some field ecological parameters of ABB that could be helpful in adopting its management strategies.

Plant essential oils (EOs) exhibit an array of biological activities against insect pests. However, their negative influences on the pheromonal activity of azuki bean beetle (ABB), Callosobruchus chinensis L., the field-to-storage pest of legumes, have not received research attentions. We evaluated the effects of three EOs and their two major components on the attractiveness of male ABBS to synthetic homofarnesal (2E- : 2Z-homofarnesal = 6:4) using Y-tube olfactometry in laboratory and rocket traps in the semi-open vinyl house. The tested EOs of Illicium verum, Croton anisatum and Gaultheria fragrantissima as well as the major components, trans-anethole and methyl salicylate ascertained significant negative effect against homofarnesal both in Y-tube olfactometry and in semi-open vinyl house tracing out a new opportunity of integrating them in ABB management programs both in field and storage.

Morphology of antennal sensilla and their distribution were investigated in male and female adults of Plautia stali,a major pest of tree fruits, using scanning electron microscopy. Antennae of P. stali was composed of a scape, a pediceland three flagella in both sexes. Four types of sensilla (s. trichodea, s. basiconica, s. chaetica, s. coeloconica) were identifiedfrom both sexes. Among them, s. trichodea and s. basiconica were multiporous, others are not. They distributed in varyingnumbers. Sexual dimorphism was not shown in the distribution of the four sensilla types. But their distribution was characterizedalong antennal segments in both sexes. This study will be useful in electrophysiological and behavioral studies on theolfactory sensory function of each morphological type of sensilla.

Morphology of antennal sensilla and their distribution were investigated in male and female adults of Ooencyrtus nezarae, an egg parasitoid of Riptortus pedestris, using scanning electron microscopy. Antennae of O. nezarae was composed of scape, pedicel and seven flagella in both sexes. Six types of sensilla (s. trichodea, s. basiconica, s. chaetica, s. campaniformia, s. sickle-shaped and unknown s.) were identified from both sexes. Among them, s. trichodea and s. sickle-shaped were multiporous, others are not. They distributed in varying numbers. Sexual dimorphism was clearly observed in the distribution of s. trichodea (only on male antennae) and unknown sensilla (only on female antennae). These findings would be helpful for further studies on detailed sex specific-receptive functions of each antennal sensilla.

Euzophera batangensis (Lepidotera: Pyralidae) is seriously damaging trunks or branches of persimmon tree (Diospyros sp.). We tested the attractiveness of (Z)-9-tetradecen-1-ol (Z9-14OH) and (Z9,E12)-tetradeca- 9,12-dien-1-ol (Z9,E12-14OH) with single or blended baits at southern parts of Korea in 2014 and 2015. The monoene was not attractive at all at three places during the two years. In 2014, diene was equally or more attractive than the mixture in Jinju and Suncheon, respectively. In 2015 too, the attractiveness of diene and mixture was not different in Jinju and Munsan. Monitoring of the seasonal occurrence of E. batangesis with the sex pheromone components revealed that it occurred three times a year; the first occurrence from early April to mid May, the second from early Jun to mid July, and the third from late August to late September.

Ooencyrtus nezarae lshii (Hymenoptera: Encyrtidae) is a major egg parasitoid of Riptortus pedestris (F.) (Hemiptera: Alydidae). One of the components of the aggregation pheromone of R. pedestris, (E)-2-hexenyl (Z)-3-hexenoate (E2HZ3H), is known to attract O. nezarae female. Response of O. nezarae females to E2HZ3H and its isomers was studied using electro-antennogram (EAG) and field tests. O. nezarae females showed higher antennal response to E2HZ3H and Z2HE3H isomers than E2HE3H and Z2HZ3H. In field tests, O. nezarae females were attracted to E2HZ3H traps, but not to Z2E3 traps. Interestingly, the blend of E2HZ3H and Z2HE3H showed significant antagonistic activities to the attraction of O. nezarae females in the field. We conclude from this study that Z2HE3H is a potent antagonist to the behavioral response of O. nezarae.