• Parasites, Hosts and Diseases
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• v.54 no.6
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• pp.777-786
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• 2016

Raillietina species are prevalent in domestic chickens (Gallus gallus domesticus) in Phayao province, northern Thailand. Their infection may cause disease and death, which affects the public health and economic situation in chicken farms. The identification of Raillietina has been based on morphology and molecular analysis. In this study, morphological observations using light (LM) and scanning electron microscopies (SEM) coupled with molecular analysis of the internal transcribed spacer 2 (ITS2) region and the nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1) gene were employed for precise identification and phylogenetic relationship studies of Raillietina spp. Four Raillietina species, including R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp., were recovered in domestic chickens from 4 districts in Phayao province, Thailand. LM and SEM observations revealed differences in the morphology of the scolex, position of the genital pore, number of eggs per egg capsule, and rostellar opening surface structures in all 4 species. Phylogenetic relationships were found among the phylogenetic trees obtained by the maximum likelihood and distance-based neighbor-joining methods. ITS2 and ND1 sequence data recorded from Raillietina sp. appeared to be monophyletic. The query sequences of R. echinobothrida, R. tetragona, R. cesticillus, and Raillietina sp. were separated according to the different morphological characters. This study confirmed that morphological studies combined with molecular analyses can differentiate related species within the genus Raillietina in Thailand.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1195-1198
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• 2006

The importance of wild plant resources along with the development of high biotecyhnology is highlighted for exploitation of new materials which can make the added value. The goal of this study is providing fundamental data bases for developing new materials through the analyses of morphological characteristics, antibiotics and molecular cytogenetics in Baegseon (Dictamnus dasycarpus Turcz.). Baegseon has several characteristics; there are two types of flower color, pink and white, the seed germination starts about February 20th, the maximum flowering season is around May 17th in southern Korea, the growth period is about 60 days. The number of chromosomes are 2n=2x=36, the size of chromosomes in metaphase is $4.2{\sim}8.1{\mu}m$. The amount of 2C nuclear DNA is 1.93pg, and there is no variation of genome size amoung varieties. The extraction juice of baegseon young roots has the excellent antibiotic activity against the mold (Botrytis cinerea).

• Journal of Ecology and Environment
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• v.41 no.1
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• pp.9-18
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• 2017

Background: Species in the heterokont genus Synura are colonial and have silica scales whose ultrastructural characteristics are used for classification. We examined the ultrastructure of silica scales and molecular data (nuclear SSU rDNA and LSU rDNA, and plastid rbcL sequences) to better understand the taxonomy and phylogeny within the section Petersenianae of genus Synura. In addition, we report the first finding of newly recorded Synura species from Korea. Results: We identified all species by examination of scale ultrastructure using scanning and transmission electron microscopy (SEM and TEM). Three newly recorded species from Korea, Synura americana, Synura conopea, and Synura truttae were described based on morphological characters, such as cell size, scale shape, scale size, keel shape, number of struts, distance between struts, degree of interconnections between struts, size of base plate pores, keel pores, base plate hole, and posterior rim. The scales of the newly recorded species, which belong to the section Petersenianae, have a well-developed keel and a characteristic number of struts on the base plate. We performed molecular phylogenetic analyses based on sequence data from three genes in 32 strains (including three outgroup species). The results provided strong statistical support that the section Petersenianae was monophyletic, and that all taxa within this section had well-developed keels and a defined number of struts on the base plate. Conclusions: The phylogenetic tree based on sequence data of three genes was congruent with the data on scale ultrastructure. The resulting phylogenetic tree strongly supported the existence of the section Petersenianae. In addition, we propose newly recorded Synura species from Korea based on phylogenetic analyses and morphological characters: S. americana, S. conopea, and S. truttae.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.39-45
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• 2017

The present study was performed to reveal the morphological characteristics and molecular phylogenetic position of Platynosomum fastosum Kossack, 1910. A total 167 specimens of P. fastosum were collected in 8 (4.9%) out of 163 sets of gall-bladders and bile ducts of cats. The number of worms was 1-105 per infected cat. This species was characterized by having a long and slender body, slightly larger ventral sucker than the oral sucker, indistinct prepharynx, small pharynx, short esophagus, bifurcation midway between 2 suckers, and ceca extending to the posterior end of the body. The length of the partial sequences of ITS1 and 5.8S rDNA of P. fastosum were 990 bp, GC-rich. AT/GC ratio was 0.9, there were 9 polymorphic sites, and intraspecific variations ranged from 0.1% to 0.9%. Phylogenetic analyses by neighbor-joining phylogram inferred from ITS1 rDNA sequences revealed that the genetic distance between P. fastosum specimens ranged from 0.3 to 1.5% while the smallest interspecific distance among dicrocoeliid species was 20.9 %. The redescription and genetic characters of P. fastosum are taxonomically important to recognize future different species of the genus Platynosomum showing high intraspecific and morphological variability.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.155-165
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• 2023

In this study, we isolated several fungal strains from filtered water and sediment collected from rivers and streams. The strains were identified by molecular phylogenetic analyses of rDNA sequences (internal transcribed spacer [ITS], large subunit of ribosomal DNA [LSU]). The morphological characteristics of the fungi were investigated using microscopy, and the culture characteristics of fungi grown on several media were examined. We identified four species previously unknown in South Korea, namely, Dissophora globulifera, Linnemannia exigua, Mortierella rishikesha and Umbelopsis autotrophica.

• Parasites, Hosts and Diseases
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• v.60 no.4
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• pp.273-279
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• 2022

Laelapinae mites are involved in transmission of microbial diseases between wildlife and humans, with an impact on public health. In this study, 5 mite members in the subfamily Laelapinae (laelapin mites; LM) were morphologically identified by light microscopy, and the phylogenetic relationship of LM was analyzed in combination with the sequence information of part of the LM cytochrome oxidase subunit I (cox1) gene. The morphological identification revealed that 5 mites belonged to the genera Laelaps and Haemolaelaps, respectively. Sequence analysis showed that the ratio of nonsynonymous mutation rate to synonymous mutation rate of LM was less than 1, indicating that the LM cox1 gene had undergone purifying selection. Phylogenetic analysis showed that the Laelapinae is a monophyletic group. The genera Haemolaelaps and Hyperlaelaps did not separated into distinct clades but clustered together with species of the genus Laelaps. Our morphological and molecular analyses to describe the phylogenetic relationships among different genera and species of Laelapinae provide a reference for the improvement and revision of the LM taxonomy system.

• The Korean Journal of Mycology
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• v.45 no.2
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• pp.145-152
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• 2017

The powdery mildew on Castanea crenata in South Korea was first recorded as Microsphaera alni in 1958. On the basis of its morphological characteristics and host range, the mildew was determined as Microsphaera sinensis in 1988. According to the rules of The International Code of Botanical Nomenclature, M. sinensis was renamed Erysiphe castaneigena in 2006. Nevertheless, taxonomic re-consideration of the morphological and molecular characteristics for the Castanea powdery mildew in Korea has not been performed. In the present study, we studied 34 powdery mildew samples collected from C. crenata in the Korea University Herbarium. On the basis of microscopic examinations of the holomorph and phylogenetic analysis of the internal transcribed spacer regions, we confirmed the powdery mildew fungus as E. castaneigena. In addition, sequence comparison between E. castaneigena and E. alphitoides ex Castanea sp. suggested a close phylogenetic affinity.

• Mycobiology
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• v.46 no.4
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• pp.305-310
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• 2018

The genus Candelaria is characterized by a micro-foliose to micro-fruticose thallus and contains eight species, two of which were reported in South Korea. During the excursion of a Korean lichen flora investigation, some suspected Candelaria concolor specimens were collected, and their morphological, chemical, molecular phylogenetic, and geographic analyses were conducted. The samples eventually proved to be a new species, Candelaria asiatica, which can be recognized by a small, yellow lobate thallus with a pulverulent surface, and a fragile lobe margin with blastidia or phyllidia-like lobules.

• The Korean Journal of Mycology
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• v.49 no.3
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• pp.379-383
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• 2021

Lactuca serriola L. (syn. L. scariola L.), commonly known as prickly lettuce, invaded Korea in the late 1970s. The plant has since become widely naturalized and disruptive to native plant communities. In May 2020, downy mildew infections were observed on L. serriola in Gimje-si, Korea. Molecular phylogenetic and morphological analyses identified the causal agent as Bremia lactucae. This is the first report of B. lactucae infection on L. serriola in Korea.

• The Korean Journal of Mycology
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• v.46 no.4
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• pp.505-510
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• 2018

Peronospora is the largest genus of the order Peronosporales (Oomycota) and contains more than 550 accepted species, which causes downy mildew on many economically important crops. During a survey of downy mildew flora in Korea, a previously unreported species of Peronospora has been found on Corydalis ambigua. Based on molecular phylogenetic and morphological analyses, the causal agent was identified as Peronospora bulbocapni. This is the first report of Peronospora bulbocapni occurring on Corydalis ambigua in Korea.