• Mycobiology
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• v.35 no.3
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• pp.159-161
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• 2007

Pine tree death caused by pine wood nematode(PWN) involves phoretic relationships between PWN and its vector Japanese pine sawyer beetle(JPS). In an effort to understand the diversity of fungi involved in PWN life cycle, a total of 176 fungal isolates were collected from PWNs, adults and larvae of JPS, PWN-diseased Japanese black pine that was cut down in 2005 at Jinju, Korea. Based on microscopic observation and colony morphology, and sequence analysis of the ITS rDNA, the fungal isolates were identified at the level of genus. Three genera including Mucor, Ophiostoma, and Penicillium were identified from PWN. Two genera of Ophiostoma and Penicillium were discovered from JPS larvae. Frpm JPS adult beetles, nine genera of Aspergillus, Gibberalla, Hypocrea, Irpex, Leptosphaeria, Ophiostoma, Penicillium, and Plectosphaerella and unknown basidio-mycetes were found. Ten genera from PWN-infected weed were confirmed as Bionectria, Botrytis, Camarops, Fusarium, Hypocrea, Nectria, Mucor, Ophiostoma, Penicillium, and Trichoderma. Penicillium and Ophiostoma were commonly distributed on PWN and its vector and host. This is first report of the fungi associated with PWN and its vector and host in Korea.

• Korean journal of applied entomology
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• v.48 no.2
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• pp.189-195
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• 2009

This study was performed to investigate the emergence timing and daily emergence from the different tree species logs (Korean white pine, Pine, and Japanese larch) at Cheongwon, Chungcheongbuk-do from 2006 to 2008. Pine sawyer adults began to emerge on early May (2${\sim}$10th day) and finished on mid-June (4${\sim}$20th day) in the Korean white pine and pine logs. However, pine sawyer adults began to emerge on mid-May (13th day) and finished late May (27th day) in Japanese larch logs, Japanese larch logs shows shorter emergence timing of pine sawyer adult compare to those of other two tree species. Emergence timing shows no difference between males and females. Sex ratios of emerged adult in 2007 were 0.55 from Korean white pine, 0.46 from Pine, and 0.59 from Japanese larch; it shows no difference among tree species. Female and male adults emerged throughout 24 hrs; 22.8% of the total adults emerged from 12${\sim}$14:00 (22.8%) and adults emerged lowest from 06${\sim}$08:00. Of the adults emerged from the logs, 98.9% was univoltine and the rest was biennial which emerged next year.

• East Asian mathematical journal
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• v.11 no.2
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• pp.223-228
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• 1995

• Korean journal of applied entomology
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• v.49 no.3
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• pp.211-218
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• 2010

Cuticular hydrocarbons (CHCs) of the pine sawyer (Monochamus saltuarius), Japanese pine sawyer (M. alternatus) and oak longicorn beetle (Moechotypa diphysis) were analyzed by GC, GC-MS and compared. Monochamus beetles are typical vectors of pine wilt disease but Moechotypa diphysis, which belongs to the same family, is not. They possess different CHCs in carbon number: 23-25 in M. saltuarius, 25-32 in M. alternatus, and 23-29 in M. diphysis. In comparison to inter-species, these three species of adult beetles have different numbers and chains of constituents of CHCs. In comparison between male and female in intra-species, the quantities of CHCs show the difference but constituents are not. Major constituent of M. saltuarius were analyzed as n-pentacosane > n-nonacosane > n-heptacosane; those of M. alternatus were n-nonacosene > n-pentacosane > n-nonacosane; and those of M. diphysis were n-heptacosane > 13-methylheptacosane > 3-methylheptacosane. From the body surface, most saturated carbohydrates of 3 species beetles are composed of n-alkane (40.2 - 65.7%) and followed by olefines > monomethylalkanes that one or two double bonds in M. saltuarius and M. alternatus. Otherwise, M. diphysis have the difference in order of monomethylalkanes > olefins.

• Korean journal of applied entomology
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• v.42 no.4
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• pp.307-313
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• 2003

Japanese pine sawyer, Monochamus alternatus, is a primary vector of pinewood nematode, Bursaphelenchus xylophilus in Korea. Emergence characteristics of the adults were studied in Jinju, Korea using dead pine logs in which the larvae of the sawyer overwintered from 1999 to 2002. Emergence data showed that the adults began to emerge out of the logs in sunny place from May the 15th in average of the four years. Cumulative emergence ratio (CER) reached at 50% at mid-June, and the emergence terminated by early or late July depending on years. In shady place, however,50% CER was reached 17 days later than in sunny place. The 50％ CER of males reached 1 to 4 days earlier than that of females depending on years. Of the adults emerged from the logs collected from February to April in 2001, 97.6％ was univoltine, and the rest was biennial which emerged from May to July of the next year. Female and male adults emerged throughout 24 hours; 32.3% of the total adults emerged from 8 to 12 a.m. It took 68.0 seconds for the adults to escape from pine logs.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.607-608
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• 2012

• Proceedings of the Korean Society of Applied Entomolohy Conference
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• 2002.11a
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• pp.89-89
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• 2002

• Korean Journal of Materials Research
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• v.6 no.2
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• pp.221-227
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• 1996

60Hz의 교류전계를 사용하는 종래의 Sawyer-Tower회로를 응용하여 0.1Hz의 직류 개념(quasi-DC)의 전계를 이용한 polarization과 strain의 동시 측정을 실시하였다. 측정의 대상으로는 강유전체로서 압전변형을 보이는 재료 중 가장 대표적인 PZT 계와 완화형 강유전체로서 전왜변형을 보이는 재료 중 가장 대표적인 PZT계와 완화형 강유전체로서 전왜변형을 보이는 재료 중 가장 대표적인 PMN계로 하였다. 0.1Hz한 주기의 전계 인가로 이력곡선을 측정할 수 있어서 시편의 발열을 크게 억제할 수 있었고 정확한 온도에서의 측정이 가능하였다. 또한 양방향 전계뿐 아니라 단방향 전계, 바이어스 전계도 인가할 수 있기 때문에 종래의 Sawyer-Tower 방법에서는 얻을 수 없는 강유전성에 관한 다양한 정보를 얻을 수 있었다. 이 방법은 또한 0.1Hz의 전계 하에서 얻을 수 없는 강유전성에 관한 다양한 정도를 얻을 수 있었다. 이 방법은 또한 0.1Hz의 전계 하에서 이력곡선이 측정되는 한 주기 동안에 시편에 부착된 스트레인 게이지를 통해 전계인가에 따른 strain 변화를 동시에 측정할 수 있기 때문에 strain과 polarization의 상관관계를 정확히 조사할 수 있다는 장점이 있다. PMN계에서 인가되는 전계의 넓은 범위에서 전왜정수 Q값을 연속적으로 구할 수 있었다.

• Journal of Forest and Environmental Science
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• v.36 no.3
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• pp.255-258
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• 2020

Pine wilt disease (PWD) caused by pine wood nematode (PWN), Bursaphelenchus xylophilus, which is transmitted by Monochamus alternatus and M. saltuarius, is a serious threat to coniferous forests in the Northern Hemisphere, including Korea. The efficacy of abamectin and emamectin benzoate for preventing the PWD in the field and its effect on the vectors Monochamus alternatus and M. saltuarius (Coleoptera: Cerambycidae) were evaluated. An experimental plot was delimited, of which consists of Japanese red pine (Pinus densiflora) forest in South Korea, and trunk injection trials were made with abamectin and emamectin benzoate. Branches of each tree were collected, and are subsequently subjected to the analysis of residues for both nematicides. Results obtained in this study showed that abamectin and emamectin benzoate showed over 90% mortality at the recommended concentration after 6 days and 8 days, respectively. Consequently, it was found that both insecticides have a higher effect on the susceptibility and persistence of two vectors of PWD, M. alternatus and M. saltuarius feeding on branches of the trees, and its application by trunk injection is confirmed as an option for pine wilt disease management programs in Korea.

• Entomological Research
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• v.48 no.5
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• pp.448-452
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• 2018

The aggregation pheromone of Monochamus (Coleoptera: Cerambycidae) beetles, 2-(undecyloxy) ethanol (hereafter referred to as monochamol), has gained considerable attention because of its usefulness in monitoring and population control of pine sawyer beetles. The hydroxyether structural motif is conserved in pheromones of the subfamily Lamiinae of the Cerambycidae. In this study, we investigated the effects of C10- and C12-chain length alkyl analogs of monochamol, 2-(decyloxy) ethanol and 2-(dodecyloxy) ethanol, on attracting M. saltuairus in Andong, Gyeongsangbuk-do, Korea. The C10 and C12 analogs attracted M. saltuarius when used in combination with ${\alpha}$-pinene and ethanol, but the responses of these alkyl chain analogs were lower than those of monochamol. Furthermore, the addition of either C10 or C12 analog to the use of monochamol with ${\alpha}$-pinene and ethanol had no effect on attraction of M. saltuarius, indicating high sensitivity of M. saltuarius to monochanol. Taken together, the results of this study suggest that chemical communication within a Monochamus species depends not only on monochamol, but also on other semiochemicals.