• Journal of agriculture & life science
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• v.53 no.3
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• pp.27-39
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• 2019

The purpose of this study was to investigate the effect of hot water treatment and pH corrected lime sulfur combination treatment on the fungicidal and bacterial disinfection effects and germination rate of organic lettuce seeds. Among the followers, Alternaria sp. was infected 53.3% and Aspergillus sp. and Cladosporium sp. Infected 14.5% and 5.4%, respectively. Bacteria were isolated only Pseudomonas sp., and infected with 16.5%. In order to investigate the effect of disinfection on the temperature of hot water (45℃, 50℃, 55℃ and 60℃). The seed germination rate sharply decreased with increasing temperature and treatment time. The germination effect and germination rate of the follower were highest when hot water treatment was carried out for 20 minutes in hot water at 50℃. In the case of combined treatment of 50℃ hot water for 10 min and 0.4% pH adjusted lime sulfur mixture, showed the highest sterilization effect and germination rate with 100% and 97.6%, respectively. The results of this study can contribute to the development of technology to sterilize not only seed surface but also fungi and bacteria inside of seed.

• Mycobiology
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• v.29 no.2
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• pp.96-99
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• 2001

Withametelin, a steroidal compound isolated from leaves of Datura metel L.(Solanaceae), showed antifungal activity against some plant pathogenic as well as saprophytic fungi tested in vitro. Except Curvularia maculans and Colletotrichum sp., spore germination of all the other 23 fungi was inhibited significantly at 125 to 1000 ppm. Out of the 25 fungi tested, Curvularia sp., Cercospora abelmoschi, Heterosporium sp., Erysiphe cichoracearum and Ustilago cynodontis were most sensitive as there was complete inhibition of germination at 1000 ppm. Similarly, spores of Alternaria brassicae, Curvularia lunata and Helminthosporium pennisetti showed less than 3% germination at the same concentration. Rest of the fungi showed more than 15% spore germination at the same concentration.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.356-360
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• 1999

Growth-inhibitory effects of citrus oils and agricultural fungicides, which were on the market, on several molds isolated from putrefied citrus fruits were investigated. When fungicidal activities of 11 kinds of synthetic agrochemicals against 6 species of molds, Alternaria alternata, Rhizopus sp., Botrytis cinerea, Monilia candida, Penicillium italicum and Penicillium digitatum, were investigated, agrochemicals containing mancozeb or fluazinam as an effective component had the broadest fungicidal spectrum. Agrochemicals containing iprodione, benomyl, azoxystrobin or thiophanate were less effective on the molds and those containing conazole derivative were intermediately effective. Resistance of the molds to the agrochemicals were species- and agrochemical-dependent. Among those molds tested, Penicillium italicum and Alternaria alternata showed relatively higher level of survival in the presence of synthetic fungicides. On the other hand, when the molds were exposed to citrus oils by direct contact, no cell could survive regardless of the species. The fungicidal activity of citrus oils was also confirmed by paper disk method and microscopic observation. These results suggested that citrus oils had broad killing activity against molds. Therefore, it would be necessary to design method for the application of citrus oils in order to improve post-harvest storage of citrus fruits.

• Korean Journal Plant Pathology
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• v.2 no.3
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• pp.165-173
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• 1986

Accumulation of Pseudomonas sp., P. fluorescens and Erwinia carotovora in 60 min treatment was greater in extracts from soil, exudate from ginseng root and solutions than distilled water. In bacterial movement toward rubber tube soil from chamber, accumulation of P. fluorescens in response to soil supplemented with soil extracts, exudate and solutions was generally greater in soil extracts compared to control and other solutions, but Pseudomonas sp. and E. carotovora were not much response to supplemented extracts, exudate and solutions. Accumulation of the bacteria in capillaries containing various exudates from fungal propagules with not attracted to the exudates. For an accumulation of bacteria in rubber tubes containing soil inoculated with fungal propagules, the Pseudomonas sp. was not attracted in soil inoculated by the organisms as attractant but P. fluorescens and E. carotovora to fungi were attracted to F. solani, F. oxysporum and mixed organism Alternaria panax did not affect on bacterial movement except E. carotovora. The organic matter conten in Kangwha and Kimpo soil were low in diseased and healthy soil. The K content was especially high in Kimpo healthy soil. Bacterial population in Goesan and Kangwha were more abundant than other soil. The number actinomycetes was populated abundant in healthy soil of Goesan and diseased soil of Poonggi.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.111-111
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• 2003

Several fungal isolates were isolated from diseased monochoria(Monochoria vaginalis, weed of paddy field), which has an resistance to sulfonyl urea(S.U.) herbicide, and were evaluated in the laboratory and greenhouse as potential mycoherbicide. Eight fungi, Alternaria sp., Colletotrichum sp., Curvularia sp., Paenicillium sp and etc. were observed in the isolates. Pathogenicity testing were done on the monochorias in the greenhouse. Monochorias were inoculated with suspensions containing conidia of each isolate at the rates of 1.0 ${\times}$ 10$\^$5/ conidia/ml and 0.1％ Tween 80 with hand-gun sprayer. Curvularia sp. and an unidentified fungal isolate caused 90-95％ mortality on the monochorias 15∼20 days after inoculation. However the other isolates induced slight symptom of disease on the monochorias. In the early stage of disease development sun-burn appearance was shown at the infected site and the last infected leaves and stems were withered to death. Subsequently the pathogenicity on the rice was evaluated with above two effective isolates. From the test an unidentified isolate showed pathogenicity on the rice but Curvularia sp., named as DBB2003, didn't. Now the mass production and formulation using Curvularia sp. DBB2003 are in progress and the field test will be followed. Combination product with Curvularia sp. DBB2003 and chemical herbicide will be more effect to control the monochoria resisted on S.U. herbicide and need to be further tested.

• Mycobiology
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• v.29 no.2
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• pp.100-103
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• 2001

Chaerophylline and berberine hydroxide, both being alkaloids, isolated from Corydalis chaerophylla and C. longipes respectively were assayed against spore germination of some fungi, e.g. Alternaria solani, A. brassicola, A. brassicicola, Helminthosporium penniseti, Helminthosporium sp., Heterosporium sp., Curvularia penniseti, C. maculens and C. palliscens. While chaerophylline inhibited spore germination of most of the fungi at 1000 ppm, being also effective at 50, 100, 200 and 500 ppm, berberine hydroxide was significantly effective at much lower concentration, i.e., 400 ppm against several fungi. This compound was also effective against some fungi at 50, 100, 150, 200 ppm. There was 100% inhibition of spore germination in several fungi at highest concentration of both the compounds. Some of the fungi showed similar results even at lower concentrations.

• Mycobiology
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• v.28 no.4
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• pp.190-192
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• 2000

Antifungal bacteria for biological control of plant diseases or production of novel antibiotics to plant pathogens were isolated in 1997 from various soils of Ansung, Chunan, Koyang, and Paju in Korea. Sixty-four bacterial strains pre-screened from approximately 1,400 strains were tested on V-8 juice agar against eight plant pathogenic fungi using in vitro bioassay technique for inhibition of mycelial growth. Test pathogens were Alternaria mali, Colletotrichum gloeosporioides, C. orbiculare, Fusarium oxysporum f. sp. cucumerinum, F. oxysporum f. sp. lycopersici, Magnaporthe grisea, Phytophthora capsici, and Rhizoctonia solani. A wide range of antifungal activity of bacterial strains was found against the pathogenic fungi, and strain RC-B77 showed the best antifungal activity. Correlation analysis between inhibition of each fungus and mean inhibition of all eight fungi by 64 bacterial strains revealed that C. gloeosporioides would be best appropriate for detecting bacterial strains producing antibiotics with potential as biocontrol agents for plant pathogens.

• Mycobiology
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• v.29 no.3
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• pp.142-144
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• 2001

The tetrahydropahnatine alkaloid was assayed against spore germination of some saprophytic and pathogenic fungi e.g., Alternaria solani, A. brassicicola, A. brassicae, A. alternata, Erysiphe pisi, Curvularia lunata, C. pallescens, C. maculans, Curvularia species, Colletotrichum species, C. musae, Helminthosporium echinoclova, H. pennisetti, H. spiciferum, and Heterosporium sp. It inhibite spore germination of all the fungi tested. Colletotrichum spp. Curvularia lunata, Helminthosporium spiciferum and Heterosporium sp. were most sensitive as complete inhibition of spore germination was observed at very low concentration(200 ppm).

• Korean Journal of Medicinal Crop Science
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• v.16 no.1
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• pp.33-38
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• 2008

This study was carried out to reduce the number of chemical treatment by optimal apply for the disease and pest and obtain the basal data of environmental-friendly cultivation in Panax ginseng in 2006. The result by checking disease Incidence and pests fried in ginseng field of jeollabuk-Do was as follows. The kind of disease occurred in Jinan was 8 including Rhizoctonia solani, 7 with Botrytis cinerea in Jeongeup, and also 6 with Botrytis cinerea in Kochang within Jeollabuk-Do. It was required thorough disease control before the rainy season because the occurrence time was peaked around July. Also, the most serious disease in Jeollabuk-Do was Alternaria alternata, Botrytis cinerera, and Colletotrichum gloeosporioides. The actual harmful pests in ginseng field were Asusta despecta steboldiana and Holotrichia sp. and in other method using black light trap, Maladera orientalis, Ostrinia furnacalis, and Holotrichia morosa were mainly trapped.

• Korean journal of applied entomology
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• v.20 no.4 s.49
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• pp.183-190
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• 1981

Alternaria sesami, A. sesamicola, A. tenuis, A. longissima, Cercospora sesami, Cephalosporium sp., Corynespora cassiicola, Fusarium equiseti, F. moniliforme, F. oxysporum, F. semitectum, Macrophomina phaseolina and Myrothecium roridum were detected from 40 seed samples of sesame. A sesami, A. sesamicola, A. tenuis and C. cassiicola were the predominant fungi. Except C. cassiicola, all fungi were almost completly reduced and wiped out the infection by pretreatment with chlorine. Plating components also indicate that C. cassiicola was well-established infections. Seedborne infection of C. cussiicola caused heavy seed rot and seedling mortality. Detailed description has been given on the habit character of C. cassiicola under stereoscopic microscope and the variation in colony character and spore morphology have been taken into account. In inoculation experiments, C. cassiicola produced severe leaf and stem spots and blights on sesame plants resulted in ultimate death of the plants. A. sesami, A. sesamicola A. longissima and C. sesami also produced mild to severe leaf spotting and leaf blight when suspension of their conidia were sprayed on to plants. In soil inoculation experiments, F. oxysporum and M. phaseolina were the most pathogenic causing seed rot and seedling blight.