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Mucosubstance Histochemistry of the Epidermis in Yellowtail, Striped Beakperch, Brown Spotted Grouper, Sea Chub, and Multicolorfin Rainbowfish

  • Jeong, Gil-Nam;Jo, Un-Bock
    • Animal cells and systems
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    • v.11 no.2
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    • pp.183-189
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    • 2007
  • To investigate the properties of mucosubstances of the epidermis in various teleostean species, conventional histochemical stainings were used on the skin in five species of order Perciformes, i. e., yellowtail, Seriota quinqueradiat, striped beakperch, Oplegnathus fasciatus, brown spotted grouper, Epinephelus chlorostigma, sea chub, Ditrema temmincki and multicolorfin rainbowfish, Halichoeres poecilopterus. The following methods were used: periodic acid Schiff (PAS), alcian blue (AB) pH at 2.5, AB pH at 1.0, AB pH at 2.5-PAS, AB pH at 1.0-PAS, aldehyde fuchsin (AF) pH at 1.7-AB pH at 2.5 and high iron diamine (HID)-AB pH at 2.5. The epidermis of all five species consisted of three layers: superficial, middle, and basal layer. The superficial layer was comprised of rather flattened cells. In particular, the outermost layer of striped beakperch and middle layer of sea chub consisted of mucus-secreting cells. Mucous cells, the unicellular glands, were found in epidermis but varied in number in different body regions and species. Although there was a slight difference in the amount in various species and body regions, the secretory contents of the mucous cells in the five teleostean species contained acidic mucopolysaccharides. In yellowtail, striped beakperch, and multicolorfin rainbowfish, the property of mucosubstances was identified as sialomucin, while it was sulphomucin in brown spotted grouper and sea chub.

Genetic Analysis of Three River Populations of Catla catla (HAMILTON) Using Randomly Amplified Polymorphic DNA Markers

  • Islam, M.S.;Ahmed, A.S.I.;Azam, M.S.;Alam, M.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.4
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    • pp.453-457
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    • 2005
  • The genetic variations in three major river populations viz. the Halda, the Jamuna and the Padma of the Indian major carp, Catla catla were analyzed by Random Amplified Polymorphic DNA (RAPD) markers. Four decamer primers were used for amplifying DNA of 10 individuals from each population. The proportion of polymorphic loci and the gene diversity estimates were 59.4 and 0.20 for the Halda, 37.5 and 0.14 for the Jamuna and 46.9 and 0.16 for the Padma populations respectively indicating the existence of a relatively high level of genetic variation in the Halda river population. The inter-population similarity indices, gene flow and genetic distance values indicated that the Jamuna-Padma population pair of catla was genetically closer than the Halda-Jamuna and the Halda-Padma population pairs in compliance with the geographical distances among them. The coefficient of gene differentiation ($G_{ST}$=0.13) reflects some degree of genetic differentiation among three populations of catla studied. The data suggest that the RAPD technique could be used to discriminate different river populations of catla.

Degradation of the Parasporal Crystal Proteins of Bacillus thuringiensis and Induction of Stress Protein Synthesis in Bt $\delta$-endotoxin Ingested Larvae of Fall Webworm, Hyphantria cunea (Bacillus thuringiensis 의 내독소 단백질의 분해와 흰불나방 섭취유충에서 스트레스 단백질 합성의 유발)

  • 전향미;유용만;강석권;서숙재
    • Korean journal of applied entomology
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    • v.33 no.3
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    • pp.178-183
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    • 1994
  • The prolein components of each crystal toxin of Bacillus thuringiensis kurstaki and alzawai were separated by SDS-PAGE. The major clqistal proteins from both shins were composed of paiypeptides having molecular weights of 130 kd and 64 kd. Digestive mixture of both. toxins with t~ypsin and gut juices shared 62 kd polypeptide which may be major actwe toxh. However, aizawal produced much less amount of 62 kd polypeptide than kurstaki did. On ingestion with Bt &-endotoxin, larvae of Hyphantria cunea developed 45 kd stress protein in the several tissues including fat body, which was induced by heat and cold shock.

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Rapid and Visual Detection of Barley Yellow Dwarf Virus by Reverse Transcription Recombinase Polymerase Amplification with Lateral Flow Strips

  • Kim, Na-Kyeong;Lee, Hyo-Jeong;Kim, Sang-Min;Jeong, Rae-Dong
    • The Plant Pathology Journal
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    • v.38 no.2
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    • pp.159-166
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    • 2022
  • Barley yellow dwarf virus (BYDV) has been a major viral pathogen causing significant losses of cereal crops including oats worldwide. It spreads naturally through aphids, and a rapid, specific, and reliable diagnostic method is imperative for disease monitoring and management. Here, we established a rapid and reliable method for isothermal reverse transcription recombinase polymerase amplification (RT-RPA) combined with a lateral flow strips (LFS) assay for the detection of BYDV-infected oat samples based on the conserved sequences of the BYDV coat protein gene. Specific primers and a probe for RT-RPA reacted and optimally incubated at 42℃ for 10 min, and the end-labeled amplification products were visualized on LFS within 10 min. The RT-RPA-LFS assay showed no cross-reactivity with other major cereal viruses, including barley mild mosaic virus, barley yellow mosaic virus, and rice black streaked dwarf virus, indicating high specificity of the assay. The sensitivity of the RT-RPA-LFS assay was similar to that of reverse transcription polymerase chain reaction, and it was successfully validated to detect BYDV in oat samples from six different regions and in individual aphids. These results confirm the outstanding potential of the RT-RPA-LFS assay for rapid detection of BYDV.

Identification of Colletotrichum spp. associated with pepper anthracnose in Korea (oral)

  • Kim, Joon-Tae;Park, Soo-Kyoung;Park, Woobong;Lee, Yong-Hwan;Kim, Heung-Tae
    • Proceedings of the Korean Society of Plant Pathology Conference
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    • 2003.10a
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    • pp.125.1-125
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    • 2003
  • Pepper anthracnose is one of the major limiting factors in pepper production. Boring last over 10 years, Colletotrichum gloeosporioides has been known as the most prevalent species among five Colletotrichum spp. involved as anthracnose causing agents. Recently, however, the change of major species with pepper anthracnose has been proposed. Identification study was peformed on 12 test isolates collected from anthracnose disease symptoms on pepper during 2001-2002 and 25 reference isolates obtained from several other host plants. The identification of the isolates with morphological observation and IfS region sequence comparison resulted that 11 ones from 12 test isolates colleted from pepper anthracnose during 2001-2002 were identified as C. acutatum. PCR using species-specific primers designed from ITS region sequence suggested a rapid diagnosis method in identifying C. acutatum from C. gloeosporioides.

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Distribution and Characteristics of PAHs in Bivalves from Gwangyang Bay, Korea

  • Yim, U.H.;Hong, S.H.;Shim, W.J.;Oh, J.R.
    • Korean Journal of Environmental Biology
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    • v.22
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    • pp.78-85
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    • 2004
  • Polyeyclic aromatic hydrocarbons (PAHs) were quantitatively determined in bivalves from Gwangyang Bay. Twenty-four kinds of target PAHs were detected in the entire samples. Total PAHs concentrations ranged 86.1∼1,210 ng g$\^$-1/ dry weight with a average concentration of 309 ng g$\^$-1/, which is much lower than those of other industrialized bays in Korea. Strong tidal currents and artificial interferences like reclamation and dredging activity were suggested as major reason for disparity between highly industrialization and low contamination status. There was no correlation between total PAHs and lipid contents, implying that lipid content is not the one major parameter for the accumulation of PAHs by bivalves. Input sources were inferred as petrogenic and pyrogenic PAHs. With help of PCA analysis, signals of seasonal variations, not only concentrations but also compositions were found.

Ecology of Sand Shrimp, Crangon affinis in the Nakdong River Estuary, Korea (낙동강 하구에 서식하는 자주새우(Crangon affinis)의 생태학적 연구)

  • HONG Sung Yun;OH Chul Woong
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.22 no.5
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    • pp.351-362
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    • 1989
  • Ecology of Crangon affinis was studied in the Nakdong River Estuary fron June 1988 to May 1989. The growth rate of female was similar to that of male. Size differences, however, were apparent between female and male. Sex ratio varies with season. The major spawning season was from June 1988 to May 1989 except for November 1988. The number of eggs of the largest ovigerous female (35.55mm TL) was over 4,000, while that of the smallest ovigerous female (15.05mm TL) more than 120. The mean number of eggs was 1778. The size of winter eggs is larger than that of the summer eggs. The mean percentage of egg loss from brooding to hatching was $29.06\%$. The rate of egg loss decreases with increasing age. Major component of food organisms includes mysids and polycheates.

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Cumacean Fauna of Southern coast and Chejudo Island in Korea (제주도와 남해 해역의 한국산 올챙이새우류)

  • Chang Mok Lee;Kyung Sook Lee
    • Animal Systematics, Evolution and Diversity
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    • v.15 no.1
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    • pp.83-105
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    • 1999
  • Thirteen cumacean species in four families were identified from the southern coast and Chejudo Island in Korea. Three of them, Campylaspis pumila Gamo, Cumella alveata Gamo, and Cumella glaberata Gamo, are recorded newly to Korean fauna. Among them, female of C. alveata is described for the first time in the would.

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Taxonomic Study of Dorylaimoidea (Nematoda : Dorylaimida) from Korea (한국산 창선충 상과의 분류학적 연구)

  • ;E. Geraert
    • Korean journal of applied entomology
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    • v.36 no.1
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    • pp.1-29
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    • 1997
  • A study on the Dorylaimoidea from Korea yielded the following fifteen species belonging to 10 different genera; Dorylaimus stagnalis, Laimydorus siddiqi, Mesodorylaimus usitatus, Sectonema basilgoodeyi, Labronema hyalinum, L. nepalense, L. vulvapapillatum, Eudorylaimus carteri, E. pseudocarteri, Ecumenicus monhystera, Discolaimus major, Enchodelus longidens, E. hopedorus, E. macrodorus, Oriverutus pagarus. They represent four families: Dorylaimidae, Aporcelaimidae, Qudsianematidae, Nordiidae.

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