• The Korean Journal of Mycology
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• v.29 no.2
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• pp.110-115
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• 2001

Nine species of Bipolaris, two species of Drechslera and two species of Exserohilum were identified from 66 isolates collected from leaf spots and leaf blights on gramineous hosts of field crops, grass pasture plants, turfgrasses and wild weeds in Korea in 1998. They included B. bicolor, B. coicis, B. cynodontis, B. maydis, B. oryzae, B. panici-miliacei, B. setariae, B. sorghicola, B. sorokiniana, D. dictyoides, D. graminea, E. oryzicola and E. turcicum. Of these, B. bicolor, B. sorghicola, D. dictyoides, and E. oryzicola were recorded for the first time in Korea.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.192-198
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• 1994

Zeaenol isolated from the culture filtrate of a fungal weed pathogen Drechslera portulacae, which causes necrosis on the leaves and stem of purslane (Portulaca oleracea). Its structure was determined by single-crystal x-ray diffraction method together with assignments of $^1H$ and $^{13}C$-NMR experiments. Zeaenol inhibited root length of Echinochloa crus-galli and Abutilon avicennae by 22.8% and 54.8% at $3{\times}10^{-6}M$, respectively.

• Applied Biological Chemistry
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• v.39 no.3
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• pp.241-244
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• 1996

A bicyclic sesterterpene from Drechslera siccans was purified and structurally characterized. During the isolation procedure, the toxic component was monitored by the assay using Italian ryegrass (Lolium multiflorum Lam.), one of the host plants of the pathogen. Siccanol (1) named arbitrarily was shown to have a molecular formula of $C_{25}H_{38}_{4}$. Siccanol completely inhibited the root growth of the Italian regrass seedlings at a level of 100 ppm.

• Korean Journal of Weed Science
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• v.14 no.3
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• pp.184-191
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• 1994

A zearalenone derivative, methyldihydroxyzearalenone has been isolated from a plant pathogenic fungus, Drechslera portulacae which causes necrosis on the leaves and stem of Portulaca oleracea. It was characterized as 3, 4, 5, 6, 9, 10-hexahydro-8, 9, 16-trihydroxy-14-methoxy-3-methyl-1H-2-benzoxacyclotetradecine-1, 7(8H)-dione on the basis of spectral analysis. Methyldihydroxyzearalenone treatment at $3{\times}10^{-5}M$ inhibited root length of Echinochloa crus-galli and Abutilon avicennae by 35.7% and 72.6% as compared with the control, respectively.

• The Plant Pathology Journal
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• v.17 no.6
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• pp.342-346
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• 2001

The physiological changes in sorghum (Sorghum vulgare Pers.) leaves infected with Drechslera sorghicola were investigated through five recognizable stages of disease development. Water-soaked yellowish brown spots developed two days after inoculation, turned brown with yellow halo, enlarged and coalesced at later stages of disease development. Healthy and infected leaves were analyzed for different biochemical constituents. The chlorophyll contents were decreased significantly with the progress of infection. The levels of reducing and total sugars increased while non-reducing sugars decreased to a significant extent with the progress of disease. The concentration of total phenolics, orthodihydroxy phenols, free and glycosidic phenols showed significant changes due to infection, whereas basic and acid phenols showed little or no change with disease development. Levels of phenolic compounds increased four days after inoculation and decrease thereafter, but the concentration was higher at every stage of disease development relative to healthy tissues. Polyphenol oxidase and peroxidase enzyme activities increased to varying degrees at different stages of infection. Analysis of protein fractions showed a significant increase with the progress of disease.

• Mycobiology
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• v.45 no.2
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• pp.73-83
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• 2017

The ability of dead cells of endophytic Drechslera hawaiiensis of Morus alba L. grown in heavy metals habitats for bioremoval of cadmium ($Cd^{2+}$), copper ($Cu^{2+}$), and lead ($Pb^{2+}$) in aqueous solution was evaluated under different conditions. Whereas the highest extent of $Cd^{2+}$ and $Cu^{2+}$ removal and uptake occurred at pH 8 as well as $Pb^{2+}$ occurred at neutral pH (6-7) after equilibrium time 10 min. Initial concentration 30 mg/L of $Cd^{+2}$ for 10 min contact time and 50 to 90 mg/L of $Pb^{2+}$ and $Cu^{2+}$ supported the highest biosorption after optimal contact time of 30 min achieved with biomass dose equal to 5 mg of dried died biomass of D. hawaiiensis. The maximum removal of $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$ equal to 100%, 100%, and 99.6% with uptake capacity estimated to be 0.28, 2.33, and 9.63 mg/g from real industrial wastewater, respectively were achieved within 3 hr contact time at pH 7.0, 7.0, and 6.0, respectively by using the dead biomass of D. hawaiiensis compared to 94.7%, 98%, and 99.26% removal with uptake equal to 0.264, 2.3, and 9.58 mg/g of $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$, respectively with the living cells of the strain under the same conditions. The biosorbent was analyzed by Fourier Transformer Infrared Spectroscopy (FT-IR) analysis to identify the various functional groups contributing in the sorption process. From FT-IR spectra analysis, hydroxyl and amides were the major functional groups contributed in biosorption process. It was concluded that endophytic D. hawaiiensis biomass can be used potentially as biosorbent for removing $Cd^{2+}$, $Cu^{2+}$, and $Pb^{2+}$ in aqueous solutions.

• Food Science and Preservation
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• v.24 no.6
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• pp.857-864
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• 2017

To establish good storage practices for hulled barley against mycotoxin contamination, we measured occurrence of fungi and mycotoxin in hulled barley grains under various storage conditions. Hulled barley grains collected from two places were stored in five different warehouses: 1) two without temperature control, 2) one with temperature controlled at $12^{\circ}C$, 3) a chamber set at $15^{\circ}C/65%$ relative humidity, and 4) one seed storage set at $10^{\circ}C$. The samples were stored for six month with temperature and relative humidity monitored regularly. Every stored samples were retrieved after 0, 1, 3, and 6 month to investigate fungal and mycotoxin contamination. From the stored grains, Fusarium, Epicoccum, Alternaria, and Drechslera spp. were frequently detected. In the warehouses without temperature control, Fusarium and Alternaria spp. constantly decreased, whereas Drechslera spp. increased along with storage period. In the other warehouses with temperature controlled, Fusarium spp. decreased slowly and more than 2.5 log CFU/g of Fusarium spp. were detected after 6 month storage. The level of nivalenol was maintained during 0-3 month but increased after 6 month storage. There was no difference in the nivalenol levels between the warehouses. Therefore reducing storage period less than 6 months could be more effective to control nivalenol contamination in hulled barley grains.

• Korean journal of applied entomology
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• v.25 no.2 s.67
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• pp.107-112
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• 1986

Species of pathogens and insects associated with grain discoloration in the Philippines were indentified. Leptocorisa oratorios was the most dominant insect species causing discoloration. Pathogenicity tests of fungal organisms isolated from discolored grains showed that Drechslera oryzae, Curvularia lunata, Trichoconiella padwickii, Sarocladium oryzae, Alternaria tenuis, and Fusarium solani were the common pathogens responsible for 'dirty panicle' disease of rice. Discoloration incidence was higher on treatment when both pests were present than when they occurred singly. The discoloration severity was attributed to the pathogens whereas rice bug caused a high decrease in grain weight and unfilled grains. Rice bug feeding on grains enhances the infection caused by the pathogen. Due to this, the quantity and quality of grains produced were affected, resulting in yield reduction.

• The Korean Journal of Mycology
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• v.14 no.1
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• pp.89-91
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• 1986

Sixteen seed samples of nine vegetable crops imported from Japan were tested for plant quarantine by routine methods of seed health testing. Nineteen species of fungi including Alternara alternata were identified from the seed samples. Some species were very frequently detected in the seeds. In this experiment, Verticillium albo-atrum, V. dahliae and Macrophomina sp. from the seeds of spinach, and Cercospora capsici, Drechslera hawaiiensis and V. albo-atrum from the seeds of sweet pepper were detected for the first time, respectively. It has been reported that they had a pathogenicity on some vegetable crops in Japan and other countries. The data suggest that an epidemic damage may be occurred if the infected seeds are sown and cultivated in Korea.

• Mycobiology
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• v.28 no.4
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• pp.185-189
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• 2000

The antifungal activity of methanolic extracts of Centella asiatica and Andrographis paniculata leaves was observed against fourteen fungi, viz., Alternaria alternata, A. brassicae, A. brassicicola, A. solani, A. tenuissima, Cercospora blumae, Curvularia lunata, C. penniseti, and Drechslera monoceras, D. oryzae, D. turitica, Fusarium albizziae and F. udum. Different concentrations of the methanolic extract (1000, 2000, 3000, 5000, 7000, 10000ppm) were used. The effect of mixed leaf extract (1500 ppm of C. asiatica + 1500 ppm of A. paniculata) and its 1:2 ad 1:4 dilutions were also studied. The individual extracts of both the plants showed significant inhibitory effect on spore germination of all the fungi tested. F. udum, F. albizzae, D. oryzae, D. turtica, and D. monoceras were particularly sensitive to these extracts. In general, the extract of C. asiatica showed a higher inhibitory effect in all concentrations against all the fungi as compared to A. paniculata, except for A. brassicae A. solani, D. oryzae, D. penniseti and Curvularia sp. The inhibitory effect of extracts increased when they were used in combination with or without dilutions against A. brassicicola, A. solani A. brassicae, A. alternata, A. tenussima, C. blumae, C. lunata, C. penniseti and Curvularia species. Higher efficacy of active ingredient of these extracts under field condition is envisaged against plant pathogens.