• Journal of Microbiology and Biotechnology
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• v.24 no.11
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• pp.1473-1483
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• 2014

Reports of herbicide resistance events are proliferating worldwide, leading to new cultivation strategies using combinations of pre-emergence and post-emergence herbicides. We analyzed the impact during a one-year cultivation cycle of several herbicide combinations on the rhizobacterial community of glyphosate-tolerant Bt-maize and compared them to those of the untreated or glyphosate-treated soils. Samples were analyzed using pyrosequencing of the V6 hypervariable region of the 16S rRNA gene. The sequences obtained were subjected to taxonomic, taxonomy-independent, and phylogeny-based diversity studies, followed by a statistical analysis using principal components analysis and hierarchical clustering with jackknife statistical validation. The resilience of the microbial communities was analyzed by comparing their relative composition at the end of the cultivation cycle. The bacterial communites from soil subjected to a combined treatment with mesotrione plus s-metolachlor followed by glyphosate were not statistically different from those treated with glyphosate or the untreated ones. The use of acetochlor plus terbuthylazine followed by glyphosate, and the use of aclonifen plus isoxaflutole followed by mesotrione clearly affected the resilience of their corresponding bacterial communities. The treatment with pethoxamid followed by glyphosate resulted in an intermediate effect. The use of glyphosate alone seems to be the less aggressive one for bacterial communities. Should a combined treatment be needed, the combination of mesotrione and s-metolachlor shows the next best final resilience. Our results show the relevance of comparative rhizobacterial community studies when novel combined herbicide treatments are deemed necessary to control weed growth.

• Microbiology and Biotechnology Letters
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• v.42 no.4
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• pp.377-385
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• 2014

In this study, a wastewater treatment system for hypersaline wastewater utilizing the Hypersaline Wastewater Treatment Community (HWTC) has been developed. The hypersaline wastewater treatment efficiency and microbial community of the HWTC were investigated. The average removal efficiencies of chemical oxygen demand were 84% in an HRT of 2.5 days. Microbial community analysis, by denaturing gradient gel electrophoresis (DGGE) of PCR-amplified 16S rRNA gene fragments and 16S rRNA gene clone library, revealed community diversity. The 16S rRNA gene analysis of dominant microbial bacteria in 4% hypersaline wastewater confirmed the presence of Halomonas sp. and Paenibacillus sp. Phylogenetic analysis suggested that the taxonomic affiliation of the dominant species in the HWTC was ${\gamma}$-proteobacteria and firmicutes. These results indicate the possibility that an appropriate hypersaline wastewater treatment system can be designed using acclimated sludge with a halophilic community.

• Korean Journal of Plant Resources
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• v.33 no.2
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• pp.116-129
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• 2020

The genus Sedum comprises about 400 taxa with worldwide distribution, and about 20 taxa of the genus Phedimus distributed from Asia to Europe. According to some taxonomists, Phedimus and Sedum are two separate genera of the family Crassulaceae; however, in Korea Phedimus has been treated as a subgenus Aizoon within the genus Sedum. This ambiguous taxonomic treatment of the genus Phedimus needs further confirmation. In the study, we investigated morphological characteristics such as the whole plant height, leaf morphology, and seed coat features of these two genera. We believe that these characters are very important to distinguish Phedimus and Sedum. The result indicated that the seed surface pattern was the most useful diagnostic character. The Sedum had a hexagonal pattern with a single nipple protrusion, whereas the Phedimus had a rectangular pattern with papilla on both ends. The results of this study strongly support the separation of Phedimus from Sedum and thus Phedimus need to be treated as an independent genus.

• Korean Journal of Plant Taxonomy
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• v.46 no.1
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• pp.13-32
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• 2016

Neillieae was traditionally recognized as a small tribe in Rosaceae, which consists of Neillia, Stephanandra, and Physocarpus. Recently, Stephanandra was merged into Neillia based on molecular phylogenetic analyses, meaning that Neillieae now contains Neillia and Physocarpus. The genus Neillia is distinguished from Physocarpus by ovate to lanceolate leaves with acuminate to caudate apices, racemose or paniculate inflorescences, and a unicarpellate (rarely bicarpellate) gynoecium. Plants of Neillia are distributed from the Himalayas across China and Korea to Japan in the east, and south to Indonesia. This study provides a taxonomic treatment of Neillia based on a morphological examination of herbarium specimens, including types, and field observations, as the second part of the taxonomic revision of the tribe Neillieae. A summary of the phylogeny of Neillia, keys to the species, nomenclatural reviews, descriptions, distribution maps, and lists of specimens examined are provided. Twelve species with ten varieties are recognized in Neillia. A lectotype was designated here for the following species: N. sinensis f. glanduligera and N. thyrsiflora.

• Korean Journal of Plant Taxonomy
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• v.51 no.2
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• pp.115-132
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• 2021

Seven species and two varieties belonging to the genus Boehmeria Jacq. (Urticaceae) are known to be distributed in Korea. Among them, B. spicata, B. tricuspis, and B. tricuspis var. unicuspis were subjected to an external morphological study. Among the individuals believed to exhibit variations in the leaf shape, B. gracilis and B. silvestrii were newly recognized. Unlike related taxa, B. gracilis has middle leaves with an elliptic, broadly elliptic, ovate, or broadly depressed ovate shape, a regular and serrulate-dentate margin, and an unlobed and short caudate or cuspidate apex. Boehmeria silvestrii has middle leaves with 5-angled ovate, orbicular ovate or broadly ovate shapes, and 3- or 5-lobed and caudate apices. Therefore, we assigned the corresponding names 'Top-geo-buk-kko-ri' and 'Cham-geo-buk-kko-ri'. Meanwhile, the B. spicata complex (B. gracilis, B. silvestrii, B. spicata, and B. tricuspis var. unicuspis) is very closely related in terms of the morphological characters, whereas B. tricuspis exhibits no relationship. Furthermore, because the scientific name and type specimen of B. tricuspis var. unicuspis (Pul-geo-buk-kko-ri) are problematic, the correct name B. paraspicata Nakai and corresponding holotype are presented. Additionally, lectotypes of B. gracilis and B. silvestrii are newly designated here. A taxonomic treatment, descriptions, a key, photographs, type specimens, and leaf variation images of the B. spicata complex are provided in this study.

• Korean Journal of Plant Taxonomy
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• v.49 no.4
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• pp.300-318
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• 2019

Many infraspecific taxa within Lespedeza maximowiczii and hybrids with related species have been described, but taxonomic verification remains controversial. We examined the morphological traits of hybrids (L. chiisanensis and L. patentibicolor) and infraspecific taxa (var. tomentella, elongata, and tricolor) and analyzed their genetic structures using microsatellite loci. Flower and leaflet shapes in var. tomentella and elongata were within the range of variation of those in var. maximowiczii, and individuals in the two former varieties were grouped into var. maximowiczii. Lespedeza maximowiczii var. tricolor was similar to L. buergeri in terms of the structure and flower color, whereas the leaflet and bracteole shapes of var. tricolor were similar to those of var. maximowiczii. Based on the genetic structure (K = 3), var. tricolor had a mixed lineage with L. maximowiczii and L. buergeri. In addition, these formed a distinct lineage at K = 5. For two hybrids, the flower and leaflet structure in L. chiisanensis did not differ from those in L. maximowiczii, whereas the flowers of L. patentibicolor were within the range of variation of L. bicolor. In addition, L. chiisanensis and L. patentibicolor were assigned to L. maximowiczii and L. bicolor, respectively, based on the genetic structure. We treated var. tomentella and elongata as a forma, f. friebeana, because L. friebeana preceded var. tomentella, whereas var. tricolor was treated as a distinct species, L. tricolor. Lespedeza chiisanensis was recognized as a synonym of L. maximowiczii. Lespedeza patentibicolor was considered to be L. bicolor.

• Korean Journal of Plant Taxonomy
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• v.49 no.1
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• pp.28-69
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• 2019

We conducted taxonomical investigations based on morphological characteristics, fruit morphology, and literature research on the tribe Potentilleae (Rosaceae) in Korea covering seven genera and 24 species. The style position on the ovary and the shape of style were useful characteristics for the classification of subtribal and generic levels in the tribe Potentilleae. The subtribe Fragariinae is characterized by subbasal or lateral style on the ovary and anthers with one theca. The subtribe Potentillinae has a subterminal style on the ovary, except for Argentina, which presents a subterminal and lateral style and anthers with two thecae. These results support the recent taxonomic recognition that i) the tribe Potentilleae consists of two subtribes, and ii) genera such as Dasiphora, Comarum, and Sibbaldianthe sometimes included in Potentilla s.l. are treated as independent genus. In the subtribe Potentillinae, Argentina, which has been treated as Potentilla, is supported as a distinct genus according to the characteristics of the subterminal and lateral style position and the ventral stipular auricles. In Fragaria, F. nipponica subsp. chejuensis, which has generally small leaves and a limited distribution only on Hallasan Mt., is supported by treatment as an endemic species. Duchesnea chrysantha is distinguished from D. indica by the characteristics of light green or yellowish green leaves, thin and somewhat membranous leaflets, and broad ovate or obovate leaflets. Each complex of P. dickinsii and P. chinensis remains unresolved with regard to controversy over the taxonomic circumscription due to their external morphological variations. Additional taxonomical research and molecular population studies are required for a more in-depth understanding of the tribe Potentilleae in Korea.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.271-278
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• 2016

Forest clear-cutting operations influence biodiversity through habitat changes and food resource availability for inhabitant species. This study examined the effects of clear-cutting on forest arthropod communities. Arthropods were collected from two different forest treatment areas (clear-cut and control) in summer and autumn. In each treatment area, arthropods were sampled from both crown and ground surfaces using sweeping and pitfall trap methods, respectively. Then, the taxonomic order of the collected arthropod specimens was easily identified. Results indicate that arthropod abundance and number of taxa present were higher at ground surface than at crown levels in both clear-cut and control areas. At crown level, more homopteran species were present in clear-cut areas than in control areas in summer. At ground surface, populations of Isopoda and Opiliones were higher in control areas than in clear-cut areas, whereas numbers of Araneae, Orthoptera, and Hymenoptera were greater in clear-cut areas. Cluster analysis and principal component analysis showed distinct differences between clear-cut and control communities at crown level in summer and at ground surface in autumn. Thus, our results indicate that clear-cutting significantly influences arthropod communities, and higher taxa are valuable for conducting rapid biological assessments of ecosystem disturbances.

• ALGAE
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• v.19 no.3
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• pp.153-160
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• 2004

The intergeneric relationship of Staurastrum complex including genus Arthrodesmus and Xanthidium was studied on the basis of mitochondrial coxⅢ sequence variation. Teiling's suggestion that Staurodesmus was an independent genus apart from genus Staurastrum, Arthrodesmus and Cosmarium was also reevaluated. The phylogeny inferred from coxⅢ gene was not consistent with morphological characteristics of Staurastrum complex. Genus Staurastrum was closely related to genus Xanthidium in the phylogenetic analysis of coxⅢ, but distant to genus Staurodesmus. The taxonomic treatment of genus Staurodesmus as an independent entity could not be determined, because Staurodesmus did not firm a monophyletic Glade. Therefore, genus Staurodesmus could not be treated as an independent genus as Prescott et al. (1982) claimed.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.103-105
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• 2013

Capparis sikkimensis Kurz subsp. masaikai (H. L$\acute{e}$v.) Jacobs, is being reported as addition to the flora of Vietnam. Line drawing of the taxon has been provided in support of taxonomic treatment and to facilitate easy identification of the species.