• Research in Plant Disease
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• v.13 no.3
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• pp.204-206
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• 2007

In 2006 to 2007, the potential inoculum source of the anthracnose of sweet persimmon caused by Colletotrichum gloeosporioides was surveyed. The infected twigs, buds, dead twigs, petiole, leaves, dropped fruits were collected and tested for their possibility as overwintering inoculum. The detection rates of the pathogen from various parts of sweet persimmon tree were varied. When the collected samples were examined in April. Over than 93.3% of infected twig samples were harbored mycelia of C. gloeosporioides, and 46.7% of infected buds, 36.7% of dead twigs, 23.3% of petioles, and 16.7% of leaves were beared pathogenic fungus. No pathogenic fungus were detecded from healthy twigs and buds. Infected twigs and bud was important overwintering sites and formed conidia actively in next spring. The infected twigs, leaves, petioles, and fruits in growing season produced great number of conidia and caused active dissemination of the anthracnose disease in sweet persimmon. In growing season, all of the infected parts, such as twigs, leaves, petioles, and fruits produced pathogenic fungus.

• Korean Journal of Plant Taxonomy
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• v.43 no.4
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• pp.285-295
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• 2013

The genus Actinidia has been recorded as having total six taxa, composed of four species and two varieties, in Korea. However, its taxonomy remains complex because of disagreement on taxonomic characters used for species boundaries. Based upon morphological, anatomical, and palynological characters, we re-evaluated species delimitations in the genus Actinidia. Critical observation of wild populations and extensive herbarium materials including types were also carried out. It is generally considered that leaf thickness and shape, hair type and color were important diagnostic characters to identify species, but these characters were insufficient to be diagnostic characters because of their wide variation ranges. On the other hands, pith pattern, winter bud protrusion rate, scale leaf number, anther color, fruit shape, and maturity season were taxonomic significance. A. arguta var. platyphylla and A. arguta var. rufinervis have been identified by hair type and color, but these characters showed continuous variation in A. arguta. Therefore, two varieties are treated as synonyms of A. arguta. Consequently four species are recognized in Korea: A. polygama, A. kolomikta, A. rufa, and A. arguta. A key is provided, as well as complete descriptions of the species examined, including information on nomenclatural types, and synonymies.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.3
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• pp.188-193
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• 2017

This study investigated the antioxidant activities of distilled water, ethanol and methanol extracts of Plunus mume flower buds (PFB). The various solvent extracts of PFB were evaluated for their total polyphenol, flavonoid, reducing power and free radical scavenging activities by FRAP and DPPH analysis. The ethanol extract of PFB contained significantly higher amounts of total polyphenols (145 mg GAE/g) and flavonoids (25.43 mg QE/g) than methanol (132 and 25.42) and distilled water (113.6 and 18.04). Among solvent extracts of PFB, the ethanol extract showed the highest antioxidant activities. The 100% ethanol extract of PFB contained significantly higher amounts of total polyphenols and flavonoids than 70% and 50% ethanol extracts. Moreover, the 100% ethanol extract of PFB showed high efficacy in DPPH radical scavenging activity and in collagenase inhibition activity. This results suggest that 100% ethanol extract of PFB has the most effective antioxidant capacity compared to the methanol and water extracts tested in the present study. Thus, it can be applied for the effective extraction of functional material from PFB for usage of cosmeceutical and/or food industries.

• Journal of Plant Biotechnology
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• v.46 no.4
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• pp.291-296
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• 2019

This study was conducted to determine the effect of a light-emitting diode (LED) on in vitro shoot growth and rooting in teak (Tectona grandis L.). In the experiments with apical bud explants, the greatest shoot elongation (3.2 cm) occurred when they were cultured on DKW medium under 50% blue and 50% red LED mixture (BR), whereas no differences in growth were observed in different light sources (florescent light [F] or BR) or media (MS or DKW). The highest number of shoot multiplication (2.4/explant) or elongation (4.94 cm) was achieved with 0.5 or 1.0 mg/L 6-Benzyladenine (BA) treatment under BR. In addition, the best rooting rate (93.8%) or root length (1.3 cm) was recorded with 0.5 mg/L indole-3-butyric acid (IBA) treatment under BR, and the highest root induction (3.1/explant) was observed in 0.2 mg/L IBA under BR. The in vitro rooted plantlets were hardened and survived well on soil.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.407-410
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• 2001

This study was conducted to determine the optimal planting distance in cultivation of yacon (Polymnia sonchifolia Poeppig ＆ Endlicher). Plug seedlings were planted with 6 different plant densities of 80 $\times$ 60, 80 $\times$ 50, 70 $\times$ 50, 70 $\times$ 45, 70 $\times$ 40 and 60 $\times$ 45 cm. The plant height and the petiole length were increased with increasing the planting distance. The tallest plant height of yacon was 165.4cm with the plant density of 80 $\times$ 60 cm. However, branch number per plant, leaf number on main stem and stem diameter were not significantly difference among planting densities. Tuberous root was harvested 31.42 tons/ha in 70 $\times$ 50 cm spacing. The ratio of heavier tuberous roots than 200 g to total tuberous roots decreased significantly according to increase of planting density. Fresh weights of shoot and root, contain the crown bud, were decreased, as planting distance was shorter. Tuberous root number was fewer but its weight was heavier in wide planting than in dense planting. We think that optimal planting density is about 30,000 plants/ha, if it were to be 70 cm row spacing, intrarow spacing should calculate about 47cm.

• The Korean Journal of Food And Nutrition
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• v.18 no.3
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• pp.254-264
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• 2005

This study was conducted to estimate the contents of heavy metals 'Hg, Cd, Pb, As, Zn, Cu, Cr, Mn' in some vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals "mean(mini.~maxi.)" ppm(mg/kg) in some vegetables(raw of perilla leaf, chard, small water dropwort, water dropwort, kale, bud of aralia, pumpkin(round type) and pumpkin(long type) were as follows : Hg : 0.0021(0.0006~0.0054)mg/kg, Cd : 0.0035(ND*~0.0377)mg/kg, Pb : 0.0191(0.0023~0.0928)mg/kg, As : 0.0757(ND~0.5294)mg/kg, Zn : 2.6299(0.4478~6.8567)mg/kg, Cu : 1.0261(0.2046~8.9417)mg/kg, Cr : 0.1535 (0.0240~0.4982)mg/kg, Mn : 3.2476(0.3283~9.8280)mg/kg. This results showed that Mn was generally simillar to previous reports and Cd, Hg, Pb were lower than other reseaches, but As was little higher or Zn, Cu, Cr were higher than the levels of those reported contents in some vegetables on domestic supermarkets in Korea, Although tolerable limit of Hg and Cd is not in a regulation of WHO/FAO, these mean levels(Pb, As, Zn, Cu) are lower than recommended levels of WHO/FAO, Pb "0.1~2.0" mg/kg, As "1.0" mg/kg, Zn "5.0" mg/kg and Cu "0.1~50"mg/kg from vegetables in 'the tolerable contents of food' by the FAO/WHO, therefor some vegetables has set to evaluate their safeties.

• Korean Journal of Agricultural and Forest Meteorology
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• v.6 no.1
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• pp.49-60
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• 2004

Northern Gyeonggi Province(NGP), consisting of 3 counties, is the northernmost region in South Korea adjacent to the de-militarized zone with North Korea. To supplement insufficient spatial coverage of official climate data and climate atlases based on those data, high-resolution digital climate models(DCM) were prepared to support weather- related activities of residents in NGP Monthly climate data from 51 synoptic stations across both North and South Korea were collected for 1981-2000. A digital elevation model(DEM) for this region with 30m cell spacing was used with the climate data for spatially interpolating daily maximum and minimum temperatures, solar irradiance, and precipitation based on relevant topoclimatological models. For daily minimum temperature, a spatial interpolation scheme accommodating the potential influences of cold air accumulation and the temperature inversion was used. For daily maximum temperature estimation, a spatial interpolation model loaded with the overheating index was used. Daily solar irradiances over sloping surfaces were estimated from nearby synoptic station data weighted by potential relative radiation, which is the hourly sum of relative solar intensity. Precipitation was assumed to increase with the difference between virtual terrain elevation and the DEM multiplied by an observed rate. Validations were carried out by installing an observation network specifically for making comparisons with the spatially estimated temperature pattern. Freezing risk in January was estimated for major fruit tree species based on the DCMs under the recurrence intervals of 10, 30, and 100 years, respectively. Frost risks at bud-burst and blossom of tree flowers were also estimated for the same resolution as the DCMs.

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.351-355
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• 1997

Adventitious shoots were induced from cambial tissue cultures of 3-year-old seedlings using BLG mineral salts medium supplemented with 10 mM glutamine and 30 mM sucrose. The optimum growth regulator level for bud induction was 4,5 $\mu$M BA which produced average 25.5 shoots per cambium segment. Induced buds were elongated on GD medium supplemented with 30 mM sucrose followed by LMG medium supplemented with 30 mM sucrose for further shoot elongation. Elongated shoots were rooted on half-strength GD medium containing $0.54 ;\mu\textrm{M}$ NAA with the frequency of 20%. This system proved the high morphogenic potential of cambial tissue in larch.

• Korean Journal of Plant Tissue Culture
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• v.24 no.6
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• pp.369-374
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• 1997

Immature flower buds of 'Desio' carnation were cultured on MS agar medium supplemented with 1 ㎎/L 2,L-D. Embryogenic calli were formed from 5-10% of the buds less than 20 ㎜ in length, but only non-embryogenic calli were produced from explants of shoot apex leaf, internode, and flowere buds larger than 20 ㎜. The same method was applied to 16 cultivars of cut Sower carnation and embryogenic calli were obtained in 7 cultivars. Several embryogenic callus lines were selected and maintained through subcultures over 120 weeks without loss of embryogenic competence. The embryogenic cultures were also proliferated rapidly in liquid agitation cultures using MS medium supplemented with 1mg/L 2,4-D. Numerous embryos were formed on the periphery of the cell aggregates upon transfer to auxin-free MS agar medium. Plantlets were transplanted in potting soil and grown to bloom in six months.

• Mycobiology
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• v.28 no.1
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• pp.54-56
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• 2000

A black scab disease occurred on sword bean (Canavalia gladiata) in plastic film houses around Chinju area during the spring season of 1999. The disease started from flower bud, then moved to flower stalk, pod, petiole, cirrus, stem and leaves. The lesions started with small dark brown spots then were gradually expanded. Severely infected plants reached 37.4% of whole plant covered with scab. Numerous conidia were produced on the diseased flower disk, pod, floral axis, stem and leaves. Most of the conidia were appeared to be readily dispersed in the air, but the mycelia were not suggested causing of sooty mold by ectoparasitism. A fungus was isolated from the diseased stem, and inoculated to healthy plants to satisfy the Koch's postulates and proved the fungus was the causal agent of the disease. The isolated fungus grew on potato dextrose agar, forming greenish black to pale brown colonies. Conidia were ellipsoidal, fusiform or subspherical, mostly one-celled but occasionally septated. The conidia were $3.9{\sim}34.1{\times}2.7{\sim}5.1\;{\mu}m$ in size and formed in long branched chains on the erected conidiophores which were pale olivaceous brown and variable in length between $7.2{\sim}210.7\;{\mu}m$ in size. Ramoconidia were $7.6{\sim}29.2{\times}3.2{\sim}14.4\;{\mu}m$ in size. The fungus was identified as Cladosporium cucumerinum based on the above morphological characteristics. The optimum temperature for mycelial growth and conidial formation was about 15 to $25^{\circ}C$. Cladosporium scab of sword bean caused by the fungi has not been reported in Korea previously.