• Journal of Plant Biotechnology
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• v.4 no.2
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• pp.67-70
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• 2002

The RAPD data were used to assess genetic similarity among f grape cultivars. Of the 100 random primers tested on genomic DNA, 10 primers could be selected for Benetic analysis, and the selected primers generated a total of 115 distinct amplification fragments. A similarity matrix was constructed on the basis of the presence or absence of bands. The 7 grape cultivars analyzed with UPGMA were clustered into two groups of A and B. The similarity coefficient value of cultivars was high. The mean similarity index for all pairwise comparisons was 0.851, and ranged from 0.714 ('Rosaki' and 'Black Olympia') to 0.988 ('Kyoho' and 'Daebong'). After due consideration of differences in cultural and morphological characteristics of these two theoretically identical cultivars, it could be deduced that 'Daebong' is a bud sport of 'Kyoho' cultivar.

• Animal cells and systems
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• v.3 no.1
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• pp.59-68
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• 1999

Chthamalus challengeri Hoek was collected from intertidal rocks to rear the larvae from hatching through nauplius to cyprid in the laboratory. Larval development consists of six nauplius stages and a cyprid. Unilobed labrum with a prominent protuberance and the frontolateral horns folded under the anterior cephalic shield margin are diagnostic features through all nauplius stages. The posterior border of the cephalic shield bears no posterior shield spines in nauplius stages IV-Ⅵ. There is a specific hispid seta in the fourth group of the antennal endopodite. Morphological features such as the cephalic shield, labrum, abdominal process, antennules, antennae and mandibles in all nauplius and cyprid stages are illustrated and described. The numerical setations of the antennule are found to aid in the intraspecific identification of barnacle nauplius stages without dissection. The keys to each stage of the barnacle larvae in Korean coastal waters are provided based on the reared nauplii of seven species: Pollicipes mitella Octomeris sulcata, Chthamalus challengeri, Balanus albicostatus B. trigonus, B. amphitrite, and B. improvisus inhabiting Korean coastal waters.

• Mycobiology
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• v.43 no.3
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• pp.343-346
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• 2015

In 2006~2010, leaf spot symptoms, that is, small, yellow spots that turned into dark brown-to-black lesions surrounded by a yellow halo, were observed on Cymbidium spp. in Gongju, Taean, and Gapyeong in Korea. A Fusarium species was continuously isolated from symptomatic leaves; in pathogenicity testing, isolates caused leaf spot symptoms consisting of sunken, dark brown lesions similar to the original ones. The causal pathogen was identified as Fusarium subglutinans based on morphological and translation elongation factor 1-alpha sequence analyses. This is the first report of F. subglutinans as the cause of leaf spot disease in Cymbidium spp. in Korea.

• Journal of Microbiology
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• v.40 no.2
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• pp.161-165
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• 2002

Isolation frequency of microorganisms from marine sources was examined with different media and samples collected from the coastal area of Cheju Island. From sea water samples, about 1% of microorganisms from the total number of bacteria were recovered. Microorganisms were cultured at the much lower frequency of 10$\^$-4/-10$\^$-6/ from other marine sources such as sediment, sponges and corals. The frequency of duplicated isolation was examined with 140 morphologically different colonies isolated on different media. Fourteen percent of them exhibited the same morphology on two different media. The duplication frequency of the isolates among three different media was 33%.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.28-35
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• 1993

Treatment of juvenile hormone analogue(JHA) at the 5th instar larvae prolonged the duration of adult development one to one and half days as well as the elongation of feeding time with the increasing of larval body weight. Morphological observation and protein analysis in hemolymphs, integuements, alimentary canals, fat bodies and ovaries also revealed that the development of these tissues and organs for adultation are affected by the JHA treatment.

• Mycobiology
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• v.37 no.4
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• pp.310-312
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• 2009

A total of 82 isolates of Colletotrichum species were obtained from anthracnose symptoms of highbush blueberry trees grown in the Gochang area of Korea during a disease survey in 2008. Out of the isolates, 75 were identified as Colletotrichum gloeosporioides and the others as C. acutatum based on their morphological and cultural characteristics. Twenty six of C. gloeosporioides isolates produced their teleomorph Glomerella cingulata in PDA culture. Three isolates of each C. gloeosporioides and C. acutatum caused anthracnose symptoms on the leaves by artificial inoculation, which were similar to what was observed in the orchards. Previously in Korea, only C. gloeosporioides has been reported as causing anthracnose in blueberries. This is the first report that C. acutatum causes anthracnose in the highbush blueberry in Korea.

• Korean Journal of Ichthyology
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• v.4 no.1
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• pp.20-28
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• 1992

The influence of starvation on morphological change and survival rate of the left eye flounder larvae was examined at the KORDI laboratories in March, 1990. 1. The larvae of left eye flounder began of feed on rotifers in 5 days after hatching. In case of non-feeding, all of the larvae died in 11 days after hatching. The larvae which fed 1 day after the normal first feeding schedule grew normally but 100 of the larvae died in 14 days when the feeding was delayed for 2 days after hatching. 2. With the exhaustion of the yolk, the total length, body length, myotome height and gut height of unfed larvae decreased. Gut height is the most decreased demensions while starving. 3. The ratio of gut height to myotome height in unfed larvae has declined most rapidly compare to other demensions during the starvation. At 13 days after hatching, the ratios of these between fed and unfed larvae were 0.797 and 0.467, respectively. 4. The morphology of starving larvae were characterized as sharpened jaw, projected edge of lawer part of clavicle and slender gut.

• Korean Journal of Ichthyology
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• v.21 no.4
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• pp.227-238
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• 2009

The egg development and morphological changes of larvae, juveniles and adults of Oryzias dancena were observed. Fertilized eggs were incubated at $25{\pm}1^{\circ}C$; the process of embryonic development was observed by light microscopy and based on diagnostic features of the developing embryos. The average time to hatch was 11 days after fertilization. The hatched larvae averaged $4.40{\pm}0.24mm$ in total length (TL). The yolk sacs of the larvae were almost absorbed at 3 days after hatching and $4.55{\pm}0.23mm$ TL. At 21 days after hatching, the larvae were $7.23{\pm}0.73mm$ TL and had reached the juvenile stage. First ovulation was about 9 weeks after hatching and at $22.58{\pm}2.73mm$ TL.

• Development and Reproduction
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• v.1 no.2
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• pp.189-202
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• 1997

The hypothalamic peptide GnRH plays a central role in the regulation of the mammalian reproductive axis. Recent studies suggested that GnRH stimulates or inhibits the ovarian steroidogenesis and gametogenesis directly. Our previous report indicated that GnRH gene is expressed in adult rat ovary as well as in hypothalamus and that the expressed GnRH may induce the follicular atresia and apoptosis of ovarian granulosa cells in rat. Therfore, we studied whether GnRH gene is expressed in the mouse fetal ovary, when the germ cells are degenerating by apoptosis during gonad diffeerentiation. Mouse fetal gonads were obtained on the 12, 15,18 and 20th day of gestation from the mother mice superovulated (10 IU PMSG and 10 IU hCG) and mated. The morphological changes of fetal ovaries were examined histochemically by hematoxylin-eosin staining. The fetal sex was confirmed by PCR methods for sexing. RT-PCR methods were used to examine the expression of GnRH gene and the sex steroid hormones were determined by conventional radioimmunoassays. The levels of estradiol (E) and progesterone (P) were increaseduntil 18th day of gestation and then E was decreased just before parturition. The morphological changes of fetal gonadal tissue sections showed the ovarian development and coincided with the result of PCR analysis for sexing using ovary- or testis- specific oligonucleotide primers. Immunoreactive GnRH in placenta was decreased gradually until the end of gestation but fetal brain and ovarian GnRH were increased. The level of GnRH gene expression was increased during fetal ovarian development from 12 till 18th day and decreased suddenly on 20th day just before birth. From these results, it is suggested that ovarian GnRh may play a regulatory role on the germ cell differentiation of fetal ovary.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.352-354
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• 1999

Randomly and specifically amplified polymorphic DNA band patterns based on polymerase chain reaction (PCR) analysis were used to assess genetic variation of somaclonal variants obtained from tissue culture of lisianthus (Eustoma grandiflorum). Five different types of variant were classified by morphological characters such as leaflet number, leaf shape, caulicle length, plant height, and leaf area. Five primers out of 20 primers (10 mer) resulted in 34 random amplified DNA fragments with polymorphisms (64.7%) in all tested plants. The dissimilarity coefficient was from 0.71 to 0.91 by UPGMA cluster analysis. Based on the presence of polymorphic bands, normal plant and five somaclonal variants were divided into two groups at the similarity coefficient value of 0.79.