• International Journal of Industrial Entomology and Biomaterials
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• v.30 no.1
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• pp.6-16
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• 2015

This study established the genetic characterisation of 10 microsporidian isolates infecting non-mulberry silkworms (Antheraea assamensis and Samia cynthia ricini) collected from biogeographical forest locations in the State of Assam, India, using PCR-based markers assays: inter simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD). A Nosema type species (NIK-1s_mys) was used as control for comparison. The shape of mature microsporidian spores were observed oval to elongated, measuring 3.80 to $4.90{\mu}m$ in length and 2.60 to $3.05{\mu}m$ in width. Fourteen ISSR primers generated reproducible profiles and yielded 178 fragments, of which 175 were polymorphic (98%), while 16 RAPD primers generated reproducible profiles with 198 amplified fragments displaying 95% of polymorphism. Estimation of genetic distance coefficients based on dice coefficients method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was done to unravel the genetic diversity of microsporidians infecting Indian muga and eri silkworm. The similarity coefficients varied from 0.385 to 0.941 in ISSR and 0.083 to 0.938 in RAPD data. UPGMA analysis generated dendrograms with two microsporidian groups, which appear to be different from each other. Based on Euclidean distance matrix method, 2-dimensional distribution also revealed considerable variability among different identified microsporidians. Clustering of these microsporidian isolates was in accordance with their host and biogeographic origin. Both techniques represent a useful and efficient tool for taxonomical grouping as well as for phylogenetic classification of different microsporidians in general and genotyping of these pathogens in particular.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.528-543
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• 2004

The biogeographical approach on the species composition, distributional range, and life form of native Korean conifers suggests that the Korean Peninsula harbors 4 families 10 genera 30 species. Early-evolved conifers maintain high species diversity and broad distribution. During the glacial periods, the ranges of cold-tolerant conifers expanded, on the other hand, those of warmth-tolerant ones reduced. Presence of endemic subalpine conifers might be the result of long-term isolation of conifers on high mountains. Horizontal and vertical ranges of native Korean conifers are classified into alpine, subalpine, montane, coastal, insular and disjunctive types, and then subdivided into twelve sub-types. Typical life form of native Korean conifers is evergreen tree, blooms in spring, and fruits ripe in autumn or following autumn. Oval and elliptical seeds with wing might be beneficial for their dispersal. Further works on the migration, dispersal, genetics, ecology of native Korean conifers are required for the better understanding of the biogeography of conifers.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.673-684
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• 2011

Shinan-gun in Jeollanam-do has 1,004 islands which is the biggest number in the whole country. As most of the islands in Korea are secluded from the mainland or other islands, biological surveys are very important for the biogeographical perspective. Especially, the species diversity of insecta on an island plays an important role in the food stability of top predators, including birds. This study provides baseline academic resources for the preservation and management of uninhabited islands by providing information about the status of insects on the uninhabited islands in Docho-myeon, Jeollanam-do, Korea. As far as the appearance aspects of the insects in 28 uninhabited islands were 921 individuals, 122 species, 60 families or 12 orders. Ga Island showed the highest appearance as 32 species, 22 families or 9 orders. Appearance of specific insects was investigated unknown species: 1 species, southern characteristic species: 3 species, coastal dune species: 1 species, climate-sensitive indicator species: 1 species.

• Animal Systematics, Evolution and Diversity
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• v.14 no.3
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• pp.173-192
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• 1998

This study was made as a part of the benethic fauna of Geojedo Island. The material was obtained from 17 localities (Fig. 1) along the coastal sea of Geojedo Island and it's adjacent waters during the years 1995-1998. This paper includes 38 species from a limited area of the southern part of Korea and includes 13 previously known species by Rho(1975-1991). Of these Didemnum (D.) pardum, Symplegma oceania, and Styela coriacea, are new to the Korean fauna, and 22 species are newly added to the fauna of Geojedo Island. We provided taxonomic notes and brief notes on the ascidian fauna, and the biogeographical distribution of Geojedo island. Its ascidian fauna are characterized by a high percentage of 18(47.4%) warm-water species and the extreme scarcity of eight(21.1%) boreal-water forms. This result may be attributable to the fact that Geojedo island and its adajacent waters are located under the influence of the warm Kuroshio Current.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.20 no.4
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• pp.192-198
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• 2015

Picophytoplankton, a group of tiny microorganisms of less than $3{\mu}m$, play an important role as a major primary producer in tropical open ocean as well as temperate coastal waters. Until now, more than 20 and 10 clades of Synechococcus and Prochlorococcus, respectively, have been identified in various marine environments, and its biogeographical distribution have been well studied as well as ecological niches of its major clades. To understand a distribution of diverse picocyanobacterial clades and environmental factors regulating their distribution, picocyanobacterial abundance and genetic diversity was investigated in adjacent waters of Dokdo showing diverse physical properties not only by seasonal variation but also by diverse physical processes. Synechococcus abundances were low in winter and then exponentially increased as water temperature increased up to $20^{\circ}C$. Above $20^{\circ}C$, the abundances tended to be saturated. On the contrary, Prochlorococcus was undetected or occupied a minor fraction of picocyanobacteria in most seasons. In summer, however, Prochlorococcus belonging to HLII ecotype occupied a significant fraction (up to 7%) of picocyanobacteria. In spring and early summer, the steep increase of Synechococcus abundances were resulted from growth of cold water-adapted Synechococcus belonging to clades I and IV. In summer, diverse Synechococcus clades including warm and pelagic water-favoring clade II tended to replace clades I and IV with maintaining high abundance. The water-column stability as well as temperature were found to be important factors regulating the Synechococcus abundances. Moreover, inflow and mixing of distinct water masses with different origins exerted significant influence on the composition of Synechococcus in the study area. Thus, physical processes as well as natural seasonal variation of environmental factors should be considered to better understand ecology of planktonic organisms around Dokdo.