• 한국산림과학회지
• /
• 제6권1호
• /
• pp.19-23
• /
• 1967

본대학묘포(本大學苗圃)의 리기다소나무 파종상(播種床)에서 입고증상(立枯症狀)의 이병묘(罹病苗)로 부터 분리(分離)한 Alternaria SP.균(菌)의 발육(發育)에 미치는 H-ion농도(濃度)의 영향(影響), 분생포자발아(分生胞子發芽)에 미치는 온도습도(溫度濕度)의 영향(影響) 분생포자형성(分生胞子形成)에 미치는 온도(溫度) 습도(濕度)의 영향(影響)에 대(對)하여 시험(試驗)한바를 요약(要略)하면 다음과 같다.1. 본균(本菌) 발육(發育)에 적당(適當)한 PH의 범위(範圍)는 4.0~9.5로 PH 간(間)의 균발육(菌發育)에 그리 큰 영향(影響)을 나타내지는 않으나 기중(其中) PH 6.5~8.0에서 발육(發育)이 가장 좋았다. 2 발생포자(發生胞子)는 $0^{\circ}C$이하(以下) $40^{\circ}C$이상(以上)의 온도(溫度)에서는 발아(發芽)가 억제(抑制)되고 $5^{\circ}C{\sim}35^{\circ}C$가 발아적온(發芽適溫)이나 기중(其中)에서 $20^{\circ}C$서 발아율(發芽率)이 가장 높았다. 관계온도(關係溫度) 10%이하(以下)에서는 발아(發芽)하지 않았고 85%이상(以上)에서 발아율(發芽率)이 좋았다. 3. 분생포자(分生胞子) $10^{\circ}C$이하(以下) $34^{\circ}C$이상(以上)에서는 형성(形成)되지 않고 온도(溫度) $22^{\circ}C{\sim}28^{\circ}C$ 범위(範圍)에서 관계습도(關係濕度) 85%이상(以上)인 경우(境遇) 형성율(形成率)이 가장 좋았다.

• Mycobiology
• /
• 제33권3호
• /
• pp.131-136
• /
• 2005

Infection structures were observed at the penetration sites on the leaves of cucumber plants inoculated with Colletotrichum orbiculare using a fluorescence microscope. The cucumber plants were previously drenched with suspension of bacterial strains Pseudomonas putida or Micrococcus luteus. The plants pre-inoculated with both bacterial strains were resistant against anthracnose after inoculation with C. orbiculare. To investigate the resistance mechanism by both bacterial strains, the surface of infected leaves was observed at the different time after challenge inoculation. At 3 days after inoculation there were no differences in the germination and appressorium formation of conidia of C. orbiculare as well as in the callose formation of the plants between both bacteria pre-inoculated and non-treated. At 5 days, the germination and appressorium formation of the fungal conidia were, however, significantly decreased on the leaves of plants pre-inoculated with M. luteus at the concentration with $1.0{\times}10^7\;cfu/ml$. Furthermore, callose formation of plants cells at the penetration sites was apparently increased. In contrast, there were no defense reactions of the plants at the concentration with $1.0{\times}10^6\;cfu/ml$ of M. luteus. Similarly, inoculation P. putida caused no plant resistance at the low concentration, whereas increase of callose formation was observed at the higher concentration. The results of this study suggest that the resistant mechanisms might be differently expressed by the concentration of pre-treatment with bacterial suspension.

• The Plant Pathology Journal
• /
• 제17권6호
• /
• pp.378.1-378
• /
• 2001

• Journal of Ginseng Research
• /
• 제22권4호
• /
• pp.304-309
• /
• 1998

Incubation condition affecting the chlamydospore formation and isolation from mycelia and conidia of Cylindrocarpon destructanse (isolate ACY-9701), isolated from the root rot lesion of the American ginseng (Panax quinquefolium) was investigated. Chlamydospores were formed from mycilia but not from conidia on the Czapek-Dox agar without carbon or nitrogen source after 20 days incubation at 2$0^{\circ}C$. In the medium added with nitrogen and carbon sources, immatured chlamy-dospore-like cells were formed from microconidia and mycelia as well. Immatured chlamydospore-like cells were formed from mycelia as well as microconidia In corn, kidney bean, and pea root extracts after 20 days incubation at 20"C, while typical chlamydospores were formed from both of them in the root extract of Panax quinquefolium. The 3.6 log chlamydospore/mm" was converted from microconidia in the medium, which was equal to 2.5% conidia formed. Under the light condition (251.1 pmol/m" sec, 12 hrs dark and light cycle), 4.2 log/mm" of chlamydospores were converted from interracially or terminal cells of macroconidia, which was 4.0% of macroconidia produced on Potato dextrose agar (PDA). When mycelia and microconidia were stored at -7$0^{\circ}C$ for 32 days and incubated on PDA after thawing at room temperature to isolate chlamydospores from them, microconidia and mycelia were still alive. Meanwhile, microconidial lysis was found after heating them at 32$^{\circ}C$ for 7 days, but the chlamydospores converted from macroconidia were not lysed up to 13 days at 32"C. to 13 days at 32"C.ot;C.

• The Plant Pathology Journal
• /
• 제15권6호
• /
• pp.345-347
• /
• 1999

A scab disease on eggplant (Solanum melongena L. cv. Chukyang) in plastic film houses around Kimhae area in Korea during the winter season of 0998-1999. The disease started on leaves with small dark brown spots which were gradually expanded to 1 to 3 mm diameter lesions. Later, the central parts of the lesions became collapsed and detached to make holes. Dark brown mold was grown out of the lesions on the lower side of leaf. Numerous conidia were produced on the lower side of leaf. Numerous conidia were produced on the diseased leaves and appeared to be readily dispersed in the air. A fungus was isolated from the diseased leaves, and tested for Koch's postulates to prove the causal agent of the desease. 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, and formed in long branched chains on the erected conidiophores which were pale olevaceous brown and variable in length between 12.4 and $393.4\mu\textrm{g}$. The fungus was identified as Cladosporium cucumerinum Ellis Arthur based on the above morphological characteristics examined. The optimum temperature for mycelial growth and conidial formation was about 20 to $25^{\circ}$. In addition to cucumber, the fungus was also pathogenic to watermelon, pumpkin and oriental melon. This is the first report on the scab disease of eggplant in Korea.

• 식물병연구
• /
• 제17권1호
• /
• pp.75-77
• /
• 2011

전북 전주시 화원에서 Botrytis cinerea에 의한 바이올렛 잿빛곰팡이병이 발생하였다. 병징은 꽃, 잎과 잎자루가 수침상으로 물러지고 부패되었다. 다습조건에서 병반위에 잿빛색의 분생포자가 많이 형성하였다. 균총은 PDA 배지에서 회갈색이며 균핵을 형성하였다. 분생포자는 단포자, 난형 또는 타원형으로 무색 또는 옅은 갈색이고, 크기는 $7{\sim}14{\times}5{\sim}9\;{\mu}m$이었다. 바이올렛에 발생한 병징과 병원균의 균학적 특징을 조사한 결과 B. cinerea Persoon:Fries에 의한 바이올렛 잿빛곰팡이병으로 명명할 것을 제안한다.

• 한국식물병리학회지
• /
• 제14권6호
• /
• pp.578-582
• /
• 1998

In greenhouse studies, control efficacy of water chestnut (Eleocharis Kuroguwai) by Epicoccosorus nematosporus was affected by temperature and dew condition. The appressoria were formed abundantly in the range of 20~28$^{\circ}C$. When stem segments o(30 cm long) of the water chestnut were inoculated with the conidial suspension of E. nematorporus, the mean conidial number attacted amounted to 2,545 conidia. Out of 2545 conidia attacted to the stem pieces, 1,733 (68%) conidia formed appressoria. When these stem pieces were treated for 24 hr at 28$^{\circ}C$ under dew condition, 183,1 (7.2%) lesions were formed 10 days after incubation. The time necessary for the death of the plants was about 24 days. Appressoria were formed at 15~35$^{\circ}C$, but decreased rapidly in their numbers at the temperature lower than 1$0^{\circ}C$ or at 35$^{\circ}C$. The appressoria formation seemed to be depended on the dew duration, which was effective to the lesion formation and plant mortality. Under dew duration of 16~24 hr with temperature range of $25^{\circ}C$ to 3$0^{\circ}C$, the weed control was increased up to 93.9%. There were no differences between the first and second or third dew treatments. A delay of 2 or 3 days in dew treatment did not increase the mortality of plants. For the use of E. nematosporus as a mycoherbicide of water chestnut, a conidial suspension should be applied when dew conditions are kept for 12 hr after inoculation.

• Journal of Ginseng Research
• /
• 제27권4호
• /
• pp.195-201
• /
• 2003

인삼 뿌리썩음병균 Cylindrocarpon destructans의 후막포자형태에 대해서 광학현미경 및 전자현미경을 사용하여 조사하였다. 전형적인 C. destructans의 후막포자는 균사로부터 형성되었으나 분생포자에서는 생성되지 않았다. 그러나 pH 4로 조절된 Czapek Dox broth에서 2$0^{\circ}C$, 12일간 배양하였을 때는 소형분생포자가 미성숙한 후막포자 유사세포로 변형되었다. 후막포자는 potato dextrose agar 및 V-8 Juice agar 그리고 질소원이 결제된 Czapek Dox broth배지에서 2$0^{\circ}C$, 16∼20일 배양으로 생성되었고, 생성된 후막포자는 황갈색 혹은 적갈색을 띄었으며 균사의 중간이나 말단 부위에서 한 개 혹은 사슬형태로 존재하였다. 후막포자는 직경이 11.3∼11.9 $\mu\textrm{m}$이었으며 외부에 1.5∼1.8 $\mu\textrm{m}$ 길이의 혹 같은 돌기가 여러 개 형성되어 표면이 울퉁불퉁 하였다.

• Mycobiology
• /
• 제50권6호
• /
• pp.467-474
• /
• 2022

Autophagy serves as a survival mechanism and plays important role in nutrient recycling under conditions of starvation, nutrient storage, ad differentiation of plant pathogenic fungi. However, autophagy-related genes have not been investigated in Colletotrichum scovillei, a causal agent of pepper fruit anthracnose disease. ATG8 is involved in autophagosome formation and is considered a marker of autophagy. Therefore, we generated an ATG8 deletion mutant, ΔCsatg8, via homologous recombination to determine the functional roles of CsATG8 in the development and virulence of C. scovillei. Compared with the wild-type, the deletion mutant ΔCsatg8 exhibited a severe reduction in conidiation. Conidia produced by ΔCsatg8 were defective in survival, conidial germination, and appressorium formation. Moreover, conidia of ΔCsatg8 showed reduced lipid amount and PTS1 selectivity. A virulence assay showed that anthracnose development on pepper fruits was reduced in ΔCsatg8. Taken together, our results suggest that CsATG8 plays various roles in conidium production and associated development, and virulence in C. scovillei.

• Mycobiology
• /
• 제28권1호
• /
• pp.54-56
• /
• 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.