• Research in Plant Disease
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• v.9 no.3
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• pp.159-161
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• 2003

Leaf spot diseases were found on safflower (Carthamus thinctorius) leaf in several fields located in Euisong-Gun, Gyengbuk province in Korea. The infected leaf rate of the diseases in surveyed area were different each years from 2001 to 2003 such as about 5%, 10%, and 30%, repectively. The typicla symptoms of diseases appeared first as small, light brown spots on leaves. And then spot turn dark brown and magnified. And yellow decoloration zone appeared surrounding dark brown spots. Mycological characteristics of Alternaria carthami, isolated from safflower mature leaf spot were dark gray colonies, conidiophores simple erect, septated, 40~80 ${\mu}m$ length; conidia solitary, straight, body size fo without beak length 40~100${\mu}m$, 10~15${\mu}m$ thick, Number of transverse septa 4~10 and longitudinal septa 4~7 ; beak with 2~4 septa, 30~65${\mu}m$ length. And A. alternata, isolated from old leaf were gray~dark gray colonies, conidiophores simple or branched, 20~110 ${\mu}m$ length; conidia long chaines, short conical or cylindrical beak, 2~6 transverse septa and several longitudinal septa, body size of without beak length 30~60 ${\mu}m$, 10~20 ${\mu}m$ thick ; beak length 5~35 ${\mu}m$. These are the first report on the leaf spot of safflower caused by Alternaria carthami, A alternata in Korea.

• The Plant Pathology Journal
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• v.24 no.2
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• pp.152-158
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• 2008

A peculiar virus-like disease of tomato showing yellow mosaic and necrotic spots on leaves and necrosis on veins, petioles and stems was observed at the Tomato Experimental Station (TES), Buyeo, Chungcheongnamdo, Korea. The disease incidence at TES fields ranged from 21 to 35% infecting different tomato cultivars. For this reason, to identify the virus infecting tomato and to characterize the virus based on biology, serology, cytology and at molecular level. Here, leaf samples were randomly collected from different infected tomato cultivars at TES fields and greenhouses and tested by ELISA using Pepper mottle virus (PePMoV) and Tomato mosaic virus (ToMV) antisera. Infected saps were mechanically inoculated in different host plants to test for pathogenicity, symptomatology and host ranges. Infected tissues and ultrathin sections were examined by electron microscopy. Finally, putative coat protein and 3'-untranslated region (CP/3'-UTR) fragment was amplified and cloned for sequence determination and analyzed its genetic relationship to existing PepMoV and PVY sequences at the Genbank. Results showed 69% of the samples were positive with PepMoV, 13% with ToMV and 19 % were doubly infected with PepMoV and ToMV. Symptoms greatly varied from different host plants inoculated with tomato leaf sap infected with PepMoV alone and discussed in detailed in this paper. Electron microscopy from infected tissues showed filamentous particles of 720-750nm in length, a typical morphology and size of PepMoV. In addition, cylindrical inclusion bodies, pinwheels, scrolls and laminates with masses of fibrillar inclusions were also found in ultrathin sections. Alignment of the sequences of the CP/3'-UTR revealed >96% sequence identity with PepMoV and only <61% with PVY. Taken together, all these evidences presented clearly indicated that the causal agent infecting tomato at TES was PepMoV and we designated this PepMoV infecting tomato as Tom-sd2 strain in this study.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.206-214
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• 2011

Fifteen clones of poplars, 2 clones of willows, and yellow poplar were used to evaluate the effects of 5 treatments such as SCBLF (slurry composting and biofiltration liquid fertilizer), general slurry liquid fertilizer, chemical fertilizer, groundwater, and control (no treatment) on vitality, growth performance, and biomass production. Five cuttings for each tree species were planted in 3 replications. After planting cuttings, a coppice was induced by cutting off stems at 10cm above the ground. Data were collected for first growing season and trees were harvested at the end of October. Maximum mortality rate i.e. 96% was recorded in the cuttings treated with groundwater and minimum 92% with control (no treatment). In all tree species, sprouting of stump was not differ significantly among the treatments. Total nitrogen concentrations of leaves and stump sprouts were higher in the treatment of SCBLF than the control, 26.6% and 22.9%, respectively. Biomass production was highest in the stumps treated with chemical fertilizer, $1.98Mg\;ha^{-1}\;year^{-1}$, and lowest in control ($1.34Mg\;ha^{-1}\;year^{-1}$).

• Research in Plant Disease
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• v.14 no.2
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• pp.112-116
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• 2008

Powdery mildew of Paprika caused by Leveillula taurica has been a serious problem in greenhouse. It is an unusual endophytic powdery mildew because the mycelia grow inside the leaf, such that the pale yellow lesions on adaxial surfaces appear first and the white powdery lesion/signs develop later on the corresponding to the spots of the abaxial leaf surface, where the conidiophores are typically emerge through the stomatal opening. Although one foliar application of cooking oil and yolk mixture(COY) to the foliage was not practically effective enough, two or three, weekly application of COY to the foliage at either 0.3 or 0.5% concentration resulted in excellent control against powdery mildew with disease index less/lower than 1, respectively. This treatment could provide protection for three weeks, which, we believe, is not only cost-effective, but also environment-friendly. Powdery mildew fungus was affected by COY treatment quickly which is recognizable in three days. Net photosynthesis and evapotranspiration was remarkably reduced by powdery mildew infection compared to healthy leaves, suggesting that prevention and early protection is the most critical strategy for peak paprika fruit yield. Moreover, COY treatment did not adversely affect the photosynthesis and evapotranspiration of foliages.

• Korean Journal of Organic Agriculture
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• v.23 no.4
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• pp.859-866
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• 2015

Virus disease surveys on barley cultivation areas in Jeonnam Jeonbuk Gyungnam Gyungbuk-do were conducted during 2014-2015. In this study, we detected Barley yellow mosaic virus (BaYMV), Barley mild mosaic virus (BaMMV) and Soil-borne wheat mosaic virus (SBWMV) by RT-PCR from barley leaves. These viruses are of great economic importance for wheat and barley, causing significant quantitative and qualitative losses in yield. The result of investigation showed that the field incidence of BaYMV in Buan, Gimje was more than 90% in 2014. The infection field rate of barley virus including Boseong, Gangjin, Haenam, Jangheung in Jeonnam was ${\approx}$ 30%. In 2014, double infections by BaYMV and BaMMV was detected in Boseong, Gangjin, Haenam and Jangheung. Only as a low rate BaYMV occurred in various fields of Jeonbuk in 2015. At the same time high infection field ratio of 70% was observed in Gunsan. Also in Yeonggwang was double infection of BaYMV and BaMMV. BaYMV occurred single infection has been confirmed in all of the study area of Gyungbuk and Gyungnam except for Goseong during the investigation period.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.21-26
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• 2010

Microbial-fermented tea (MFT), which is made by microorganisms through fermentation, is a popular beverage in Asia, especially in the Yunnam province, China. In this study, changes of the chemical constituents and antioxidant activity during the manufacturing process of MFT were investigated. MFT were respectively prepared from fresh leaves of three different tea species (Yabukita, Daecha, and Korean wild cultivar) and a processed green tea (Korean wild cultivar). The color of the tea infusions gradually changed to red and yellow as a function of fermentation time. Total nitrogen and caffeine contents were not significantly changed. Whereas, the chlorophyll, tannin, and total catechins contents gradually decreased. Interestingly, the epicatechin and epigallocatechin contents increased up to 25 days of fermentation and then decreased. Change of the chemical constituents of all samples showed the same patterns. The antioxidant activity of MFT from Daecha and Yabukita slightly decreased as increasing fermentation time. However, the range over which the antioxidant activity of MFT from Korean wild cultivar and green tea were not changed. This research suggests that it may be possible to manufacturing possibility of MFT using Korean wild cultivar and processed green tea.

• Journal of Life Science
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• v.23 no.1
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• pp.1-7
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• 2013

Understanding salt tolerance mechanisms is important for the increase of crop yields, and so, several screening approaches were developed to identify plant genes which are involved in salt tolerance of plants. Here, we transformed the Arabidopsis cDNA library into a salt-sensitive calcineurin (CaN)-deficient ($cnb{\Delta}$) yeast mutant and isolated the colonies which can suppress salt-sensitive phenotype of $cnb{\Delta}$ mutant. Through this functional complementation screen, a total of 34 colonies functionally suppressed the salt-sensitive phenotype of $cnb{\Delta}$ yeast cells, and sequencing analysis revealed that these are 9 genes, including CaS, AtSUMO1 and AtHB-12. Among these genes, the ectopic expression of CaS gene increased salt tolerance in yeast, and CaS transcript was up-regulated under high salinity conditions. CaS-antisense transgenic plants showed reduced root elongation under 100 mM NaCl treatment compared to the wild type plant, which survived under 150 mM NaCl treatment, whereas CaS-antisense transgenic plant leaves turned yellow under 150 mM NaCl treatment. These results indicate that the expression of CaS gene is important for stress tolerance in yeast and plants.

• The Korean Journal of Mycology
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• v.37 no.1
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• pp.104-107
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• 2009

Mitrula paludosa (Geoglossaccae, Helotiales, Ascomycetes) is reported about morphological and ecological characteristics for the first time in Korea. The mushroom fruited on rotten pine leaves or fine twigs in ditches with flowing or standing water in Sogri Mountain National Park from May to June. The apothecium of M. paludosa is 20 to 50 mm tall. The cap is bright yellow to orange, cylindrical to wrinkled ovoid and $5{\sim}10\;{\times}\;10{\sim}20$ mm. The stem is whitish and cylindrical distinctly set off from the cap. The ascospore is hyaline, smooth long elliptical fusoid with round ends and $13{\sim}17\;{\times}\;1.5{\sim}2.0{\mu}m$. The ascus is unitunicate, $90{\sim}110\;{\times}\;5{\sim}6{\mu}m$, and has eight spores biseriately lined to the inoperculate apex. Paraphyses are septate filiform, $95{\sim}120\;{\times}\;1.0{\sim}1.5{\mu}m$, $7{\sim}10{\mu}m$ longer than the asci.

• The Korean Journal of Zoology
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• v.8 no.2
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• pp.89-127
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• 1965

1. This report is on the outcome of observation made up the breeding process of Narcissus flycatcher, Muscicapa narcissina zanthopygia, using 15 ness-boxes at Seoul and Kwang Nung Experimental forest in 1964, and the relevant feeding habit was studied by the collar method of wrapping the necks of thenestlings for 50-60 minutes or more in some cases from 1963 to 1964. 2. The Narcissus flycatcheris a common summer resident throughout Korea arriving at the end of April. The earliest data of arrival of this species in Seoul, is April 26, 1964. They migrate southward from the later part of September to early part of October. 3. In a week after their arrival , they start to build nest after a brief courtship. Male and female prepare their nest ina nestboxes in 4 or 5 days. Nests are usually found in the moss, which provide definite frame-work. The inner side of the nest is usually composed of roots of Gramineae or leaves of pine, oak or other broad leave tree. 4. The laying period is generally from the later part of April to the middle of June : and the number of eggs laid is from 3 to 8 , therefore 5 in average : eggs are pink with traces of milky yellow blending of light auburn and orange red spots and chicken-egg-like in shape. 5.The incubation takes place for 7-12 days from the middle part of May to the middle of June, in the order of male and female . The hatching rate tends to increase in proportion to clutch size. 6. The feeding period usually lasts 15 days in average from the early part of June to the middle of July and the feeding urge tends to increase in proportion to brood size. 7. The animals invading into their nest-boxes are red ants, chipmunks, bees , barkbeetles and philippine red-tailed shirkes, etc. 8. On the basis of analysis covering 714 birds in 31 nests, the food they consumed during the nesting period of nestlings were mostly of animal matters composing of : insect larvae form-39. 88% insect adult form 36.26%, insect pupae-0.19%, spider-17.75% and other animal matters 5.92% , Besides a small amount of plant pieces were found . As to the insect larvae, Lepidoptera was the largest in the content followed by Hymenoptera , Orthoptera and Coleoptera. As to the insect adult, Diptera was the largest in the content followed by Coleoptera, and Hymenoptera. In view of forest protection, noxious insect was of 69.38%, useful insect 4.39%, and spider 17.75%. 9. The rich assortment of its food, the ability of acquiring various insect (adults as well as larvae), its destruction of great numbers of harmful insects , and its quick assimilation artificial nesting with the nest-boxes of 2.5-3cm entrance hole employed, allow us to conclude that the flycatcher may be successfully employed in the elimination of fores pests. The above results are only that part obtained near Seoul in the middle of Korea, however, if we would extend the scheme to other broad areas using similar techniques, the nest-boxes could not only be well used by the birds, but also it would help to prevent the increase of harmful. insects.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.101-104
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• 2016

Curvularia leaf blight of creeping bentgrass (Agrostis stolonifera) putting green by caused Curvularia trifolii was observed in Hapcheon, Korea. In July to September 2014, curvularia leaf blight developed on leaf blades of creeping bentgrass as small water-soaked lesions that subsequently turned into dark-colored, necrotic spots. The spots were expanded and became gray, grayish-brown, or light brown, circular to oblong lesions with purple to dark brown borders that often were surrounded by a yellow halo. The necrotic lesions coalesced, became irregular in shape and caused tip or complete blighting of the leaves. Blighted leaf blades appeared grayish-white to tan. The fungus was identified by morphological characters and 16S rDNA sequencing as C. trifolii. Conidia of the pathogen were short, with predominantly 3-septa, straight or often curved, with end cells frequently paler than intermediate cells. Size of the 3-septate conidia in culture are $26{\sim}28{\times}11{\sim}12{\mu}m$. Pathogenicity of the fungus was proved by artificial inoculation on the host. This is the first report of C. trifolii causing leaf blight on creeping bentgrass in Korea.