Locations In Korea Research Articles

Pseudocercospora leaf spot caused by Pseudocercospora nymphaeacea on Nymphaea tetragona

Pygmy waterlily (Nymphaea tetragona, Nymphaeaceae) is a perennial aquatic herb with floating leaves and beautiful flowers. Leaf spot on pygmy waterlilies appeared in 2009 at several locations in Korea, e.g., Suwon in 2009, Yangpyeong in 2011, and Seoul in 2014. The leaf spots were circular to irregular, small, and brown in the center with a dark brown margin. The spots later became milky white. The causative agent of the leaf spot was identified as Pseudocercospora nymphaeacea. Morphological observations and multigene phylogenetic analyses of the internal transcribed spacer (ITS), the partial translation elongation factor 1-alpha (TEF-1α), and actin (ACT) regions are provided. The pathogenicity test was conducted twice with similar results, which fulfilled Koch’s postulates. To our knowledge, this is the first report on P. nymphaeacea infection of N. tetragona.

Three New Records of Mortierella Species Isolated from Crop Field Soil in Korea

Three new fungal species of the genus Mortierella, Mortierella zychae, Mortierella ambigua, and Mortierella indohii, have been reported in Korea. The fungi were encountered during a study on the fungal community of soil samples collected from different locations in Korea. The species were identified based on molecular and morphological analyses. This study presents detailed descriptions of the morphological observations and molecular phylogenetic analysis of these three fungi. All three species were found to be sensitive to triphenyltetrazolium chloride staining. M. zychae demonstrated the highest intensity of mycelial staining, indicating that this species has the highest potential to produce arachidonic acid of the three species. The staining results indicated that the newly recorded species could potentially be useful for arachidonic acid production.

A new species and ten new records of bdelloid rotifers from Korea.

We conducted a taxonomic study of bdelloid rotifers collected from various terrestrial habitats, such as mosses, lichens, mushrooms on tree trunks, and leaf litter, at six different locations in Korea. The study yielded 10 new Korean records and a new species, Bradyscela hoonsooi n. sp. Among the 10 new Korean records, nine species are new to Asia, and seven of these are rare species with poorly known distributions. Our study is the first to record Habrotrocha fuscochlaena De Koning outside its type locality. Macrotrachela sonorensis Örstan and Habrotrocha acornis Murray have previously been reported from only two countries. Habrotrocha longula Bryce and Habrotrocha visa Donner are recorded outside Europe for the first time. Habrotrocha flaviformis De Koning has previously been reported from Europe, Brazil and New Zealand. Finally, Philodina grandis Milne has been reported from Eastern and Southern Africa and New Zealand before the present study. Here, we provide a description of the new species and discuss the taxonomy and distribution of the seven rare species.

Reappraisal of nine species of Martensia (Delesseriaceae, Rhodophyta) reported from Korea based on morphology and molecular analyses

Abstract Previous taxonomic studies reported that nine species of Martensia (i.e., Martensia albida, Martensia australis, Martensia bibarii, Martensia elegans, Martensia flammifolia, Martensia fragilis, Martensia jejuensis, Martensia projecta, and Martensia palmata) occur on the Korean coast. Our recent Martensia collections from various localities in Korea contain many specimens with a huge range of morphological variation and are difficult to classify into the named species. In this study, we analyzed DNA sequences of rbcL and COI genes to access their phylogenetic relationships and to verify taxonomic status based on morphological observations. The molecular analyses revealed that only two species of Martensia occur in Korea (M. albida and M. jejuensis). Martensia albida is characterized by having entire margins of blades with a single band of networks, whereas M. jejuensis is distinguished from the other species by possessing projections along the margins of the networks and blades. Both molecular analyses and morphological observations revealed that M. flammifolia is a member of the genus Nitophyllum. Some features (e.g., thallus habit, branching patterns, blade morphology, positions of reproductive structures) are not reliable for species identification. Our results indicate that the rbcL and the COI gene have sufficient resolution for delimitation at both species and generic levels in the subfamily Nitophylloideae.

Sustainable Water Distribution Strategy with Smart Water Grid

Many problems that are encountered in regards to water balance and resources management are related to challenges of economic development under limited resources and tough competition among various water uses. The development of major infrastructure like airports in remote areas that have limited water resources is becoming a common problem. In order to overcome these difficulties, water management has to articulate and combine several resources in order to respond to various demands while preserving the ecological quality of the environment. The paper discusses the interest in implementing the Smart Water Grid concept on Yeongjongdo Island, which is the location of Korea’s main airport. This new concept is based on the connection of various water resources and their optimized management with new information technology solutions. The proposed system integrates water generated through rainfall, external water resources (i.e., metropolitan water distribution system), gray water and other types of alternative water resources. The paper analyses the feasibility of this approach and explores interest in the Smart Water Grid concept.

국내에 자생하는 일부 Cirsium 속 식물들의 분자유전학적 유연관계 분석

Cirsium chanroenicum, Cirsium nipponicum, and Cirsium schantarense plants were collected from Changwon, Ulleungdo, and Dooryoon Mountain, respectively. Cirsium japonicum plants were also collected from various locations in Korea. Genomic DNA was prepared from the collected plants and used for amplification of the 18S rDNA, ITS1, 5.8S rDNA, ITS2, and part of 28S rDNA. The ITS1 and ITS2 sequences of the PCR products and from other Cirsium plants reported previously were aligned and compared. Cirsium chanroenicum, Cirsium nipponicum, and Cirsium setidens formed distinct branches on the neighbor-joining tree. Cirsium japonicum and Cirsium pendulum appeared to be close to one another, but Cirsium pendulum plants were clearly clustered in an independent clade. Cirsium shantarense was clustered with the other Cirsium japonicum plants. The most important characteristic that distinguished these two species was the direction of the flowers. All Cirsium japonicum flowers point upward, but Cirsium shantarense flowers point downward. Other than this feature, these two spe cies are almost indistinguishable morphologically. Cirsium chanroenicum is indistinguishable morphologically from Cirsium setidens, but it still formed a distinct group on the neighbor-joining tree based on ITS sequences, suggesting that this sp ecies is worth considering as an independent species. Silymarin production of the collected plants was analyzed and appeared to be quite high, indicating that the ability to synthesize silymarin is common to all Cirsium plants analyzed so far.

A New Record of Neosartorya aureola Isolated from Field Soil in Korea

A new species of Neosartorya was recovered during investigation of the fungal community in soil samples collected from different locations in Korea; Neosartorya aureola KNU14-7 was isolated for the first time from field soil in Korea and identified based on the internal transcribed spacer region of rDNA and morphological characteristics. The species has not been officially reported from Korea and we report it here with description and figures.

Accuracy Comparison of Air Temperature Estimation using Spatial Interpolation Methods according to Application of Temperature Lapse Rate Effect

Since the terrain of Korea is complex, micro- as well as meso-climate variability is extreme by locations in Korea. In particular, air temperature of agricultural fields is influenced by topographic features of the surroundings making accurate interpolation of regional meteorological data from point-measured data. This study was carried out to compare spatial interpolation methods to estimate air temperature in agricultural fields surrounded by rugged terrains in South Korea. Four spatial interpolation methods including Inverse Distance Weighting (IDW), Spline, Ordinary Kriging (with the temperature lapse rate) and Cokriging were tested to estimate monthly air temperature of unobserved stations. Monthly measured data sets (minimum and maximum air temperature) from 588 automatic weather system(AWS) locations in South Korea were used to generate the gridded air temperature surface. As the result, temperature lapse rate improved accuracy of all of interpolation methods, especially, spline showed the lowest RMSE of spatial interpolation methods in both maximum and minimum air temperature estimation.

Analysis of the Phenolic Content and Antioxidant Activities of Soybean Extracts from Different Regions and Cultivars

Phenolic compounds such as isoflavones contribute to the antioxidant properties of soybean. This study investigated differences in the phenolic content and antioxidant activity of ten soybean cultivars grown in two different locations in Korea. We observed a wide range of variation in total isoflavone and phenolic content by location and cultivar. The total isoflavone content of cultivars grown at Pyeongchang (sub-highland) was significantly higher than that in cultivars grown at Gangneung (lowland). In contrast, the total phenolic content of cultivars grown at Gangneung was greater than that of cultivars grown at Pyeongchang. The radical scavenging activity of DPPH was similar to that of the total phenolic content rather than that of the total isoflavone content. These results suggest that antioxidant activity of soybean was associated with phenolic compounds rather than isoflavones. To identify the individual antioxidant components, we used an on-line HPLC-ABTS + -based assay system, ESI/MS, and NMR. The results showed that the strongest antioxidant activity was linked to epicatechin.

Population structure and sequence divergence in the mitochondrial DNA control region of gizzard shad Konosirus punctatus in Korea and Japan

To investigate the extent of genetic differentiation among populations, genetic polymorphism in gizzard shad Konosirus punctatus, collected from wild populations of eight locations in Korea and four locations in Japan, was examined using mitochondrial DNA (mtDNA) control region. Two distinct mitochondrial lineages were detected: Lineage A was only distributed around Korean coastal waters and dominates the western and southwestern coast group of Korea. While Japanese groups of K. punctatus were exclusively assigned to lineage B. The co-occurrence of both lineages in southeast and east coasts of Korean coastal waters indicated that the current distribution pattern of gizzard shad populations was constructed by secondary contact.

Four Unrecorded Species of Tubificid Oligochaetes (Annelida: Clitellata) in Korea

Tubificid oligochaetes are common and frequently dominant in freshwater benthic habitats. They are so tolerant to water pollution that they are often used as biological indicators. Faunistic studies of Korean freshwater oligochaetes have been actively conducted recently. The most well studied oligochaete family in Korea is the tubificids following the naidids. Nine species of tubificids have been reported so far. Nevertheless, many species of tubificids still remain to be discovered in Korea. In this study, we added four species of tubificid oligochaetes to the Korean fauna, including Linmodrilus profundicola (Verrill, 1871), Potamothrix heuscheri (Bretscher, 1900), Tubifex blanchardi <TEX>$Vejdovsk\acute{y}$</TEX>, 1891, and Ilyodrilus templetoni (Southern, 1909) based on specimens collected from three locations in Korea: Cheonan-si, Geoje-si, and Seocheon-gun. In particular, P. heuscheri was first reported in Asia.

Zonate Leaf Spot of Prunus mandshurica Caused by Hinomyces pruni in Korea

Zonate leaf spots and severe defoliation were observed on Manchurian apricot (Prunus mandshurica) growing in a humid location in Korea from 2011 through 2013. The main symptoms included greyish green to brownish grey and zonate leaf spots without border lines, which mostly led to premature defoliation. The morphological characteristics of the causal agent were consistent with Hinomyces pruni. Identification was supported by analysing the sequence of the internal transcribed spacer region of ribosomal DNA from an isolate. The pathogenicity of the isolate was confirmed by artificial inoculation. This is the first report of zonate leaf spot caused by H. pruni on Manchurian apricot globally as well as in Korea.

The study of the calculation of energy consumption load for heating and cooling in building using the Laplace Transform solution

The Laplace Transform solution is used as a mathematical model to analyse the thermal performance of the building constructed using different wall materials. The solution obtained from Laplace Transform is an analytical solution of an one dimensional, linear, partial differential equation for wall temperature profiles and room air temperatures. The main purpose of the study is showing the detail of obtaining solution process of the Laplace Transform. This study is conducted using weather data from two different locations in Korea: Seoul, Busan for both winter and summer conditions. A comparison is made for the cases of an on-off controller and a proportional controller. The weather data are processed to yield hourly average monthly values. Energy consumption load is well calculated from the solution. The result shows that there is an effect of mass on the thermal performance of heavily constructed house in mild weather conditions such as Busan. Building using proportional control experience a higher comfort level in a comparison of building using on-off control.

First Report of Powdery Mildew Caused by Golovinomyces sonchicola on Ixeris chinensis in Korea.

Ixeris chinensis (Thunb.) Nakai, known as Chinese ixeris, is distributed from Siberia to Japan, including Korea, Taiwan, and China. The whole plant has been used in folk medicine in Asia (4). In Korea, the plants of Chinese ixeris have been gathered and used as a wild root vegetable. During summer to autumn of 2011, Chinese ixeris leaves were found to be heavily infected with a powdery mildew in several locations of Korea. Symptoms first appeared as thin white colonies, which subsequently developed into abundant hyphal growth on both sides of the leaves, leading to drying of the leaves. The same symptoms on Chinese ixeris leaves were continuously observed in 2012 and 2013. Voucher specimens (n = 10) were deposited at Korea University Herbarium (KUS). Hyphal appressoria were moderately lobed or nipple-shaped. Conidiophores arose from the lateral part of the hyphae, measured 100 to 270 × 10 to 12.5 μm, and produced 2 to 6 immature conidia in chains with a sinuate outline. Basal parts of foot-cells in conidiophores were curved. Conidia were barrel-shaped to ellipsoid, measured 26 to 36 × 13 to 19 μm (length/width ratio = 1.7 to 2.4), lacked fibrosin bodies, and showed reticulate wrinkling of the outer walls. Primary conidia were ovate with conical-obtuse apex and subtruncate base. Germ tubes were produced on the perihilar position of conidia. Chasmothecia were not observed. The morphological characteristics were typical of the Euoidium type anamorph of the genus Golovinomyces, and the fungus measurements and structures were consistent with those of G. sonchicola U. Braun & R.T.A. Cook (1). To confirm the identification, internal transcribed spacer (ITS) region of rDNA sequences from a representative material (KUS-F26212) was amplified using primers ITS5/P3 and sequenced (3). The resulting 416-bp sequence was deposited in GenBank (Accession No. KF819857). A GenBank BLAST search revealed that the isolate showed >99% sequence similarity with those of G. cichoracearum from Sonchus spp. (e.g., AB453762, AF011296, JQ010848, etc.). G. sonchicola is currently confined to G. cichoracearum s. lat. on Sonchus spp., based on molecular sequence analyses (1). Pathogenicity was confirmed through inoculation by gently pressing a diseased leaf onto leaves of five healthy potted Chinese ixeris. Five non-inoculated plants served as controls. Inoculated plants developed symptoms after 6 days, whereas the controls remained symptomless. The fungus present on the inoculated plants was identical morphologically to that originally observed on diseased plants. Powdery mildew infections of I. chinensis associated with Golovinomyces have been known in China (2). To our knowledge, this is the first report of powdery mildew disease caused by G. sonchicola on I. chinensis in Korea. Farming of Chinese ixeris has recently started on a commercial scale in Korea. Though no statistical data are available, we postulate the cultivation area in Korea to be approximately 200 ha, mostly growing without chemical controls. Occurrence of powdery mildews poses a potential threat to safe production of this vegetable, especially in organic farming.

Hydrocarbon pollution does not influence bacterial diversity as much as geographic location: a Korean case study

Bacterial diversity of hydrocarbon-contaminated sites in various regions of Korea was investigated to ascertain the influence of hydrocarbon pollution on bacterial diversity using terminal restriction fragment length polymorphism (T-RFLP) and differential gel gradient electrophoresis. Thirty-two hydrocarbon-contaminated soil samples were collected from seven different geographical locations in Korea. A dendrogram of T-RFLP profiles for the bacterial community structure in soil samples using Ward’s method with Jaccard distance showed that samples from the same location clustered together. Principal components analysis (PCA) and self-organizing maps (SOM) of terminal restriction fragments were also used to characterize the associations among samples. PCA and SOM results also showed that soil bacterial communities were classified according to locations, but not by hydrocarbon pollution level. Moreover, correlation analyses prove a direct correlation between bacterial diversity and meteorological parameters, whereas no significant correlation was observed with hydrocarbon contamination levels. These results suggest that geographical origin, rather than soil contamination level, might be more important in determining the bacterial diversity of crude oil-contaminated soils. Environmental factors, which play a major role in determining natural bacterial diversity which in turn should be enriched for effective bioremediation, should be the central dogma while considering bioremediation of hydrocarbon-contaminated sites.

Eight new records of monogonont and bdelloid rotifers from Korea

The rotifers collected from a brackish water zone as well as various terrestrial habitats such as mosses, ichens, and leaf litter at seven different locations in Korea were investigated. Eight species/subspecies belonging to five genera in five families of monogonont and bdelloid rotifers new to Korea were identified: Encentrum incisum, Encentrum uncinatum, Cephalodella innesi, Adineta gracilis, Macrotrachella timida timida, Macrotrachella timida inquies, Habrotrocha pavida and Habrotrocha scabropyga. Five bdelloids are new to Asia as well. Notably, these eight Korean new records included three rare species. H. scabropyga is recorded outside its type locality for the first time. For M. timida timida, this study is the third record after its description. In addition, E. incisum has been reported only from Austria, Germany and Russia before the present study.

Composition of Polyphenols and Antioxidant Activity of Garlic Bulbs Collected from Different Locations of Korea

Composition of Polyphenols and Antioxidant Activity of Garlic Bulbs Collected from Different Locations of Korea

온실 내 재배 채소와 함께 발생한 버섯의 동정 및 특성

Unusual mushrooms were observed in the greenhouses of vegetables Chinese chive, cucumber, melon and Korean dandelion in four locations of Korea in 2012. The mushrooms usually grew with the vegetables cultivated on beds in the greenhouses. Occurrence aspects of the mushrooms in the greenhouses and effect of the mushrooms on growth and quality of the vegetables were investigated. Mushroom samples were collected from the beds in the greenhouses and identified based on their morphological characteristics. The mushroom samples collected from the greenhouse of Chinese chive were identified as Coprinus aokii, those from the greenhouse of cucumber as Cristinia eichleri and Coprinus sp., those from the greenhouse of melon as Leucocoprinus cretaceous, Panaeolus fimicola and Conocybe sp., and those from the greenhouse of Korean dandelion as Conocybe rickenii f. tetrasporique. Out of the seven mushrooms identified, L. cretaceus, C. rickenii and C. eichleri were first found in Korea. The investigation results revealed that the mushrooms were originated from compost or soil used in the beds, and showed that C. aokii caused sooty mold on leaves of Chinese chive, and C. rickenii f. tetrasporique hindered growth of Korean dandelion and caused sooty mold on leaves of the plant. The other mushrooms had no effect on growth and quality of the vegetables.

오이 노균병의 생물적 방제를 위한 Bacillus amyloliquefaciens CC110균주 선발

Pseudoperonospora cubensis에 의한 오이 노균병의 생물적 방제를 위하여 오이 재배단지의 오이 식물체 126균주를 분리하였다. 그 중에서 잎 절편 생물검정 통하여 5균주를 선발하였다. CC110균주는 오이노균병 예방과 치료효과 검정에서 전혀 병이 발생하지 않았지만 무처리는 15.0~18% 노균병이 발생하였다. CC110균주는 gyrB gene sequence 분석에 의하여 Bacillus amyloliquefaciens subsp. plantarum로 동정하였다. CC110균주를 TSB배지에서 배양한 배양액은 LB, NB와 KB 배지에서 배양한 배양액보다 오이 노균병 발생이 적어 효과적이었다. CC110균주를 TSB배지에서 배양한 배양액의 원액, 2배와 5배 희석한 처리구에서 0%, 3.0%와 8.0% 그리고 배양여액을 원액, 2배와 5배 희석한 처리구에서 0%, 4.0%와 7.0% 노균병이 발생하였고, 무처리는 21.0% 발생하였다. 오이 유묘검정에서 CC110균주를 TSB배지에서 배양한 배양액은 오이 노균병이 35.0% 발생하였고 무처리는 82.0% 발생하였다. 비닐하우스 포장에서 오이 노균병에 대하여 B. amyloliquefaciens CC110균주를 5일 간격 4회 처리가 7일 간격 3회 처리보다 방제효과가 높았다. In order to select antagonists for biological control of downy mildew of cucumber, 126 bacteria were isolated from cucumber plants collected from several locations in Korea. Among them, Five isolates were selected as potential biocontrol agents of cucumber downy mildew using a leaf disc bioassay method. In preventive and curative effect tests, the isolate CC110 was found to be effective to control downy mildew on cucumber showing diseased area by 0% whereas that of control was 15.0~18.0%. A bacterium isolate CC110 was identified as Bacillus amyloliquefaciens subsp. plantarum based on phylogenetic analysis using gyrB gene sequence. The culture liquid of isolate CC110 in TSB media were more effective for the control of the disease than those cultured in LB, NB, and KB media in leaf disk bioassay. when undiluted liquid, two-fold, five-fold diluted culture broth, and undiluted liquid, two-fold, five-fold diluted filtrate of isolate CC110 in TSB media were treated, diseased area of cucumber powdery mildew were 0%, 3.0%, 8.0%, 0%, 4.0% and 7.0%, respectively, whereas diseased area in the control was 21.0%. In the cucumber seedling tests, when the culture broth of isolate CC110 in TSB media was treated, diseased area were 35.0%, whereas that of control was 82.0%. When B. amyloliquefaciens CC110 was treated four times at five-day interval in the vinylhouse test, the control effect of cucumber downy mildew was higher than that treated three at seven-day interval.

동북아시아 꽃매미 날개 변이의 형태계측학 분석

Morphometric analysis of Lycorma delicatula was performed to confirm whether local individuals had a geographical difference in their wing variations. The L. delicatula individuals were collected from 10 localities in Korea, China, and Japan, and 14 morphometric characteristics selected from the forewing were analyzed. The Korean individuals were similar to the ones from the northern area of the Yangtze River, but less similar to the others from the southern area of the Yangtze River. The individuals from Seoul and Buan were very similar to those from Shanghai. In case of wing spots, the individuals from Beijing had relatively small spots, while the ones from Linan had big spots. The Japanese individuals had a relatively large wing size.