Yong-Gu Han
Daejeon University
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Yong-Gu Han.
Entomological Research | 2011
Youngho Cho; Deuk-Soo Choi; Yong-Gu Han; Sang-Ho Nam
Hipparchia autonoe, designated Natural Monument no. 458, is a species inhabiting Mt. Halla on Jeju Island, which is the only habitat of H. autonoe in South Korea. Recently, this species is in danger of extinction as the population has been remarkably reduced because its host plants and nectar plants are gradually disappearing due to plant succession in its habitat. On the climbing road of Jeju Island Eorimok, H. autonoe used to be observed at and above 1300 m a.s.l. However, since Sasa quelpaertensis has recently expanded its habitat up to 1400 m, H. autonoe is now observed at and above 1500 m. In Mongolia, the population of H. autonoe seems quite stable as there are dense populations of a host plant and nectar plants. Accordingly it is judged that we can maintain a stable community for support of H. autonoe if we successfully manage the host plant and nectar plant communities by controlling the density of S. quelpaertensis using biological and physical control methods. Comparative analysis of DNA barcode region of COI (658 bp) was done to check the homogeneity and the genetic diversity of H. autonoe collected in Korea and Mongolia. The DNA sequence difference among individuals collected in South Korea was 0.0–0.2%, and in Mongolia 0.0–1.4%. This confirmed a 0.06–1.2% barcoding gap. We believe that this result will provide basic information useful to guide conservation of H. autonoe in South Korea.
Journal of Korean Nature | 2010
Seong-Joon Park; Youngho Cho; Youngjin Kim; Yong-Gu Han; Heon-Myoung Lim; Seo-Kyoung Park; Eu-Jeong Hong
We investigated insect fauna of Is. Boleum-do from April to October, 2009. As a result of all the collections examined, 162 species of 59 family under 11 order were identified. Therefore, the species composition of insect diversity from Is. Boleum-do was a total of 228 species of 77 families under 11 orders including 3 endangerd species (level, Fabriciana nerippe, Lethocerus deyrollei and Copris tripartitus), 22 endermic species, 3 management of exotic species, 1 species of IUCN Red List and 42 designated species; 103 species of 18 families Lepidoptera (35.76%) which was the highest, 51 species of 18 families Coleoptera (17.72%), 44 species of 15 families Hemiptera (15.28%) and 37 species of 6 families Hymenoptera (12.85%).
Entomological Research | 2011
Youngjin Kim; Youngho Cho; Yong-Gu Han; Sang-Ho Nam
Endoparasitoids of Anomis privata larvae include five species in three families of two orders. In this work, two species of Hymenoptera Braconidae (Cotesia sp., Microplitis sp.), one species of Ichneumonidae (Mesochorus vittator) and two species of Diptera Tachinidae (Exorista (Podotachina) sorbillans, Timavia amoena) were investigated. Of the 261 larvae of A. privata examined, 32 had a parasite, so the rate of parasitism was 12.26%. Parasitism by taxon was the highest, at 10.35% (27 individuals), in Cotesia sp. in Hymenoptera Braconidae. Parasitoids of Braconidae and Ichneumonidae were larval parasitoids. A parasitic insect of Tachinidae was a larva–pupal parasitoid. Solitary parasitoids included Microplitis sp. in Braconidae and E. sorbillans in Tachinidae. Gregarious parasitoids included Cotesia sp. in Braconidae, M. vittator in Ichneumonidae and T. amoena in Tachinidae. There was also a multiparasitoid (T. amoena) and two superparasitoids (Cotesia sp., M. vittator). A larva of A. privata sought feed even after it was parasitized every parasitoid investigated in this study, so five species of parasitoids were all koinobiont.
Entomological Research | 2010
Youngho Cho; Youngjin Kim; Yong-Gu Han; Young Kook Kang; Min-Joo Choi; Heon-Myoung Lim; Young-Jun Park; Sang-Ho Nam
Six species of insect endoparasitoids were identified from Elcysma westwoodii, which is the most damaging lepidopteran pest of Prunus yedoensis. From Hymenoptera, two species were identified: a species in Braconidae and Charops striatus in Ichneumonidae. From Diptera, there were four species in Tachinidae: Compsilura concinnata, Exorista sp., Pales sp. and Tachinidae spp. The parasitic ratio was 4.86% (45 of 926 larvae). The hymenopterans were parasitic on 31 individuals of E. westwoodii (68.9%) and the dipterans were parasitic on 14 individuals (31.1%). It was found that parasitoids from the larvae of E. westwoodii were all either endoparasitoids or larval parasitoids. However, Exorista sp. of Tachinidae was found to be either a larval parasitoid or larval‐pupal parasitoid. Additionally, all the identified parasitoids were solitary parasitoids, as only one parasite occurred in a larva of E. westwoodii. Because the larva of E. westwoodii eats and molts after it is parasitized, all the parasitoids were identified as koinobionts. There were no big differences in morphological characteristics and life histories between C. striatus and C. concinnata. However, for Exorista sp. and Pales sp., males took 3–5 days longer to emerge from their pupae and had remarkably longer body lengths than females.
Entomological Research | 2009
Yong-Gu Han; Youngho Cho; Youngjin Kim; Heonmyoung Lim; Ohseok Kwon; Sang-Ho Nam
The annual herb Bidens frondosa L., native to North America, is an invasive weed. Currently no information is available on the insect herbivores associated with this weed in Korea. A survey was carried out at two‐weekly intervals from May to October 2008 at two sites, and the incidence and abundance of various insect herbivores studied. A total nine species of insects was recorded and among them the defoliating caterpillar Hadjina chinensis (Wallengren) (Lepidoptera) was the only species known to have host plants restricted to genus Bidens. Further host specificity studies are required to evaluate the potential of this insect as a candidate for augmentative biological control agent for B. frondosa in Korea. All other insect species are either polyphagous or known crop pests.
Journal of Ecology and Environment | 2015
Yong-Gu Han; Youngho Cho; Ohseok Kwon
Laboratory Animal Research | 2010
Young-Kook Kang; Hong-Sig Oh; Youngho Cho; Youngjin Kim; Yong-Gu Han; Sang-Ho Nam
Journal of Ecology and Environment | 2015
Yong-Gu Han; Youngho Cho; Ohseok Kwon; Young-Kook Kang; Young-Jun Park; Youngjin Kim; Min-Joo Choi; Sang-Ho Nam
Journal of Ecology and Environment | 2015
Tae-Geun Kim; Yong-Gu Han; Ohseok Kwon; Youngho Cho
Journal of Ecology and Environment | 2015
Yong-Gu Han; Ohseok Kwon; Youngho Cho