稻熱病菌의 變異와 對策

鄭厚燮 서울大學校 農科大學 1978 서울대농학연구지 Vol.3 No.4

딸기 시들음병균에 대한 Trichoderma 속 균의 길항작용에 관한 연구 : Ⅳ. Antagonism of T. harzianum in Soils Ⅳ. 토양에서의 T.harzianum 길항작용

문병주,정후섭,조종택 東亞大學校生命資源科學大學附設 農業資源硏究所 1994 農業生命資援硏究 Vol.3 No.2

In vitro에서 볏짚, 밀기울, 옥수수분말, chitin 또는 게껍질을 첨가하면 T. harzianum의 딸기 시들음병균에 대한 길항작용은 높았으나 clover 잎 분말에서는 낮았다. 또한 이 길항작용은 25∼30℃, 산성토양(pH 3.5-5.5), 40∼50%의 토양수분에서 촉진되었다. When rice straw, wheat bran, corn, chitin or crabshell powder was added in soil in vitro, the antagonistic activity of T. harzianum on F. oxysporum f. sp. fragariae increased, whereas incorporation of clover leaf powder had no effect on the antagonistic activity. The activity was also the highest at 25∼30℃ and in acid soil(pH 3.5∼5.5) with 40∼50% moisture content.

벼의 잎 ·목 稻熱病에 대한 抵抗性의 比較

權寧閑,鄭厚燮,趙鏞涉,朴恩雨 서울大學校 農科大學 1986 서울대농학연구지 Vol.11 No.1

1. Differences in reactions of leaf and neck of rice plants to rice blast among four rice cultivars were observed in a paddy field. Cultivars Jinheung and Milyang 23 showed susceptible and resistant reactions, respectively, on both leaf and neck. Cultivar Norin 6 was susceptible to leaf blast and became intermediately resistant to neck blast whereas cultivar Ginga showed resistant and intermediately resistant reactions on leaf and neck, respectively. 2. Three different heading dates at 5 to 8 day intervals were induced by transplanting seedlings of four cultivars from seedling beds to a paddy field three times at 9 to 10 day intervals. When blast severity was compared within cultivars, leaf blast severity increased as heading dates became late. However, neck blast severity was greater in plots with early heading dates than those with late heading dates. 3. Spore germination of two isolates of Pyricularia oryzae in tissue extracts from leaf and neck of four rice cultivars indicated significant interactions between cultivars and isolates. However, spore germinations in leaf and neck extracts were not significantly different. Mean degree of hyphal growth of four P. oryzae isolates on the sheath adaxial epidermis indicated significant interactions between cultivars and isolates. 4. Some anatomical characteristics of leaf and neck of four cultivars did not have apparent relationship with the reactions of four cultivars to rice blast in the paddy field. Also, the amounts of the total nitrogen, sugar, P₂O??, and SiO in flag leaf and neck were not significantly different among four cultivars and did not seem to affect changes in reactions of cultivars Norin 6 and Ginga to leaf and neck blasts observed in the paddy field.

딸기 시들음병균에 대한 Trichoderma 속 균의 길항작용에 관한 연구 : Ⅲ. Chitinase and β-1,3-glucanase Activity Ⅲ. Chitinase와 β-1,3-glucanase 활성

문병주,정후섭,조종택 東亞大學校生命資源科學大學附設 農業資源硏究所 1994 農業生命資援硏究 Vol.3 No.1

T. harzianum은 합성 배지에 유일한 탄소원으로서 chitin, laminarin, 본 병균의 세포벽, 밑기울 분말, clover잎 분말, maltose를 단독으로 첨가하여 생육시키면 chitinase와 β-1, 3-glucanase를 생성하였으나, chitinase 활성은 세포벽 첨가구에서 가장 높았고 다음은 chitin이었으며 maltose와 밑기울에서도 높은 활성을 보였으나 clover에서는 극히 낮았다. β-1, 3-glucanase 활성은 maltose에서 가장 높았고 다음은 laminarin이었으며 그 이외에는 극히 낮았다. 양 효소의 활성은 pH 3.5와 5.5가 pH 7.5에 비하여 높았으며, T. harzianum과 본 병균을 혼합하면 단독배양에 비하여 높았다. T. viride도 유일한 탄소원으로서 chitin 또는 laminarin을 첨가하면 각각 chitinase와 β-1,3-glucanase를 생성하였으나, chitinase 활성은 T. harzianum에 비하여 현저하게 낮았고 β-1,3-glucanase의 활성은 비슷하였다. Chitinase production by Trichoderma harzianum was highest in the culture with cell walls of the pathogen or chitin, moderately high with maltose or wheat bran, and very poor with clover leaf power. Relatively large amount of β-1,3-glucanase was excreted by T. harzianum when maltose or laminarin was used as a sole carbon source for the culture of the fungus, whereas cell walls, wheat bran and clover leaf powder had little effect on the enzyme production. For both of the enzymes, the enzyme activities were higher at pH 3.5-5.5 than at pH 7.5, and higher enzyme activities were detected in the dual culture of T. harzianum and Fusarium oxysporum f. sp. fragariae than in the culture of T. harzianum alone. The activity of chitinase by T. viride was significantly lower than by T. harzianum, and the activity of β-1,3-glucanase was similar between the two antagonisitcs, although T. viride produced chitinase and β-1,3-glucanase when chitin or laminarin was added as a sole carbon source.

菜蔬의 連作障害에 關한 硏究 : I.菜蔬連作障害實態 I. Present Status of Soil Sickness in Continuous Vegetable Cropping

李炳馹,鄭厚燮,林善旭 서울大學校 農科大學 1983 서울대농학연구지 Vol.8 No.1

Present status of soil sickness in continuous vegetable cropping was investigated by means of interviews and field surveys. Investigations were made major vegetable crops such as Chinese cabbage, radish, red pepper, garlic,cucumber and others in the field or in the plastic house where a known vegetable crop was cultivated continuously for a long period. 1. In Chinese cabbage both for summer and autumn crops, bacterial soft rot was the most destructive one and followed by club root, root rot and boron deficiency in that order. 2. No serious soil sickness was generally observed in certain root crops such as radish and carrot except that root knot of carrot in Cheju. However,radish was damaged occasionally by Fusarium yellows and boron deficiency. 3. In general,Phytophthora rot and bacterial wilt were severe in red pepper, while nematode damages and bacterial canker occurred in a limited area. 4. With cucurbits,cucumber,muskmelon,and watermelon, although Fusarium wilt and stem blight were severe, those could be controlled by grafting Powdery mildew, grey mold and downey mildew occurred freqeuntly in the plastic house. 5. There were almost free from soil sickness problems in bulbous vegetable crops, garlic, onion and shallot. However root mite damage of shallot was severe and percentage of garlic blight has increased as increasing continuous cropping period with poor cultural practices. 6. Strawberry has damaged greatly by Fusarium yellows with incrcasing bud blight and that the cultivation is shifting toward the disease free land. 7. In lettuce, Sclerotinia soft rot, downey mildew and bacterial soft rot were prevalent and marginal leaf spot caused by Pseudomonas species on heading lettuce was severe in some areas. 8. There were severe damages of peanut due to root knot and Cercospora leaf spot while occasionally bacterial soft rot, and deficiencies of calcium and boron were observed in celeries.

Special Lectures : THE PROGRESS AND RESEARCH TRENDS OF MYCOLOGY IN THE REPUBLIC OF KOREA

( Hoo Sup Chung ) 한국균학회 1993 KOREA CHINA JOINT SEMINER Vol.- No.-

Double - stranded RNAs from Rhizoctonia solani

( Hoo Sup Chung,Sam Jae Jun,Yong Hwan Lee ) 한국균학회 1995 95 SECOND JOINT SEIMINAR Vol.- No.-

ANTAGONISTIC EFFECTS OF THE MICROFLORA OF BARLEY LEAVES ON THE PATHOGENICITY OF HELMINTHOSPORIUM SATIVUM

Chung, Hoo Sup 서울대학교 1958 서울대학교 論文集 Vol.7 No.-

1. 여러가지 病徵을 나타내는 보리잎에서 2 isolates의 Xanthomonas translucens, 7 isolates의 bacteria와 各 1 isolate의 Alternaria sp., Aspergillus niger, Eusarium sp., Saccharomyces sp., Helminthosporium sativum을 分離하였다.이들 徵生物의 分離頻度는 斑點病徵과 關聯이 있었다.卽 斑點이 甚할 때보다 輕할 때에 Xanthomonas translucens, Fusarium, bacteiar를 더 많이 分離하였다. 2. H. sativum에 對한 microfloral organisms의 拮抗的 影響을 여러가 方法으로 試驗하였다.Xanthomonas translucens 1, bacterium 7, bacterium 17, Aspergillus niger와 H. sativum을 같은 petri plate에 서로 나란히 자라게 하여 阻止帶를 이루었고 Alternaria sp., Fusarium sp.는 H. sativum의 colony 위를 덮어서 자랐다. 3. 阻止帶를 이룬 各 microfloral organism을 미리 섞은 培養基上에서 H. santivum의 radial growth와 胞子形成은 顯著이 줄었다. 4. Bacterium 17과 Aspergillus niger의 低濃度인 代謝物質을 加한 培養基上에서 H. sativum의 radial growth는 顯著하게 줄었다.Xanthomonas translucens 1, X. translucens 2, bacterium 7, bacterium 14, bacterium 15, bacterium 20에 依해서는 많은 sector를 誘發하는 以外에 特別한 影響은 없었다. 5. H. sativum의 分生子 發芽와 發芽管의 生長은 榮養液에 있는 microfloral organisms에 依해서 抑制되었다. H. sativum의 分生子 發芽 抑制率은 Aspergillus niger를 除外하고서 다른 試驗에서 본 拮抗現象과 相關的이었다.Xanthomonas translucens의 두 isolates는 H.sativum에 對한 拮抗的 影響이 서로 달랐다. 6. 切斷한 보리잎이나 자라는 보리잎에 H. sativum의 分生子와 各 microfloral organism을 섞어서 接種한 結果 H. sativum의 病原性은 매우 減少되었다.자라는 보리잎에 있어서 가장 病原性을 減少시킨 것은 Fusarium sp.이었고 Xanthomonas translucens 1, bacterium 17, bacterium 7의 順序인데 그 range는 대개 39∼57%였다.다른 isolates에 依해서는 中間으로 부터 조그만큼 病原性을 減少시켰다.대체로 H. sativum의 分生子 發芽 抑制率과 病原性의 輕減은 相關的이었다. 7. 各 microfloral organism과 H. sativum의 分生子를 함께 섞어서 接種했을 때와 各 microfloral organism을 뿌린 2日 後에 H. sativum을 接種한 때와는 큰 差異가 없었다. 8. 보리잎의 microflora는 H. sativum의 生長, 發芽, 病原性에 對하여 여러 程度로 拮抗的이라고 할 수 있다. 9. Microflora의 멤버는 圃場에서 斑點病을 防除함에 어느 程度 도움이 된다고 結論지었다. 1. Fourteen microfloral organisums, namely, 2 isolates of Xanthomonas translucens, 7 isolates of bacteria, and one each of Alternaria sp., Aspergillus niger, Fusarium sp., Saccharomyces sp., and H. sativum, were isolated from barley leaves which had various symptoms. The frequency of these organisms was associated with the severity of spot blotch. When spot blotch symptoms were light, Xanthomonas translucens, Fusarium, and bacteria were found more frequently than when the symptoms were severe. 2. Antagonistic effects of microfloral organisms on H. sativum were tested by various techniques. Pairing of isolates of Xanthomonas translucens 1, bacterium 7, bacterium 17, and Aspergillus niger with H. sativum in the same petri plate resulted in wide zones of inhibition. Fusarium sp. and Alternaria sp. overgrew the colonies of H. sativum. 3. Marked reduction in radial growth and sporulation of H. sativum occurred on media previously seeded with microfloral organismas that also produced a zone of inhibition. 4. When cultural filtrates of bacterium 17 and Aspergillus niger were added to the medium in low concentration, radial growth of H. sativum was markedly reduced. Except for induction of abundant sectoring, no conspicuous effects were obtained by adding isolates of Xanthomonas translucens 1, X. translucens 2, bacterium 7, bacterium 14, bacterium 15, and bacterium 20 to the substrates. 5. Conidial germination and germ tube growth of H. sativum were inhibited by microfloral organisms present in the nutrients medium. The percentage of inhibition of conidial germination of H. sativum was correlated with the degree of antagonism in other testes involving growth except for the isolate of Aspergillus niger. The two isolates of Xanthomonas translucens differed in their antagonistic effects on H. sativum. 6. Detached leaves and growing plants were inoculated with conidia of H. sativum in combination with microfloral organisms. Fusarium sp., Xanthomonas translucens 1, bacterium 17, and bacterium 7, greatly reduced pathogenicity of H. sativum. On growing plants, the most effective was Fusarium sp. followed by Xanthomonas translucens 1, bacterium 17, and bacterium 7. The range of disease reduction brought about by these isolates was from 39 to 57 percent. Moderate and slight reduction in pathogenicity were caused by other isolates. In general, there was a correlation between the percentage inhibition of conidial germination of H. sativum and the amount of reduction in pathogenicity. 7. There were no apparent differences in severity of infection when different microfloral organisms were simultaneously applied with H. sativum respectively or when H. sativum was inoculated 2 days following the application of microfloral organisms. 8. The microflora of barley leaves were found to be antagonistic to growth, germination, and pathogenicity of H. sativum in varying degrees. 9. It is concluded that members of the microflora are responsible for some measure of spot blotch control in the filed.

人蔘·炭疸病 關한 研究 : 傳染源, 病原菌의 生態, 發病要因 및 防除

Hoo-Sup Chung,Hyo-Won Bae 한국응용곤충학회 1979 한국응용곤충학회지 Vol.18 No.1

인삼탄저병에 감염된 포기의 종자에는 , 겉으로 건전한 포기의 종자에도 의 탄저병균을 보유하고 있었으며, Fusarium, Alternaria, Phoma, Trichoderma 등도 많이 분리되었다. 탄저병균은 실내에 있는 잎의 조직에서 18개월간 생존하였으며, 옥외의 노지, 지하 10, 30cm에서도 월동할 수 있었다. 인삼잎에 탄저병균의 분생자를 접종하였을 때에 발병하였고, 이하에서는 전혀 병반이 형성되지 않았다. 암흑구, 400룩스구에서 탄저병반은 미소하였고, 1200룩스구에서 중정도, 직사광선에서는 극심하였다. 그리고 연령이 어린 잎일수록, 분생자수가 많을수록 병반면적율은 높았다. 병원균의 균사생장 및 분생자형성의 최적온도는 였고, 균사생장의 최적 pH는 2.8-4.2였으며 분생사형성은 5.2-5.8이었다. 포장에서 살균제와 인삼탄저병균의 분생자를 함께 3년생식물에 처리했을 때 방제효과가 큰 것은 difolatan 그리고 maneb, zineb, captan, phaltan의 순위였으며 ferbam과 보르도액은 약간 낮았다. Four to of the seeds of ginseng (Panax ginseng Meyer) collected from seemingly healthy plants carried Colletotrichum panacicola Nakata et Takimoto whereas the seeds from the plants with anthracnose sympotoms carried of the same fungus. Prevalent organisms isolated other than C. panacicola from seeds of both kinds of plants were Fusarium, Alternaria, Phoma, Trichoderma and others, ana in that order on acidified potato sucrose agar. C. panacicola also was isolated from 18 months old herbarium specimens. The fungus in the infected tissues also survived during the Korean winter months either on the soil surface or in the soil at 10 and 30 em in depth. When conidial suspensions of C. panacicola were inoculated on detached ginseng leaves, anthracnose symptoms occurred from 25 to . No symptoms occurred at temperatures below . Direct sunlight increased significantly the number of anthracnose lesions over those obtained in leaves inoculated in darkness or in 400 lux of fluorescent light. The lesions decreased as age of the leaves increased or as the number of conidia applied decreased. Optimum temperature for mycelial growth and conidial formation of C. panacicola was . Optimum pH for the mycelial growth was at while the most conidial formation occurred at . When fungicides were applied in the field to ginseng plants with a conidial suspension of C. panacicola, the most effective control of the anthracnose disease was by spraying with difolatan, and followed by maneb, zineb, captan and phaltan, Bordeaux mixture and ferbam were significantly less effective but significantly better than the inoculated control plants.

韓國에서의 새로운 稻熱病菌의 레이스

Hoo Sup Chung 한국응용곤충학회 1974 한국응용곤충학회지 Vol.13 No.1