• Research in Plant Disease
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• v.16 no.1
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• pp.94-96
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• 2010

In May of 2004 through 2007, Leptosphaerulina leaf blight caused by Leptosphaerulina trifolii occurred on Kentucky bluegrass (Poa pratensis) at golf courses in Gangwon Province, Korea. Symptoms on the turfgrass caused by L. trifolii were leaf blights, dying from the leaf tip downwards to the crown, which appeared patches in the field because of local pockets of severely infected (blighted) grass. Perithecia were produced on old or weak leaves, including club-shaped asci, each of which contained 8 pale brown muriform ascospores with cross and longitudinal septa. Ascospores of the fungus isolated from the diseased leaf tissue and cultured on potato-dextrose agar (PDA) were muriform multicellular (composed of 3-6 cells) and $23.4-40.5{\times}7.8-15.6{\mu}m$ in size with 3-4 transverse and 0-3 longitudinal septa, which were morphologically identical to L. trifolii reported previously. DNA sequences of ribosomal RNA gene (internal transcribed spacer) of the fungus were homologous with similarity of 99% to those of L. trifolii isolates in GenBank database, confirming the identity of the causal agent of the disease. Pathogenicity of the fungus was also confirmed on the creeping bentgrass by Koch's postulates. This is first report of Leptosphaerulina leaf blight on turfgrass caused by L. trifolii in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.67-71
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• 1984

These experiments were conducted at field and green house in order to screen the resistant sesame varieties to Phytopthora nicotianae var. parasitica. and to ascertain the infection conditions of Corynespora cassiicola at different temperatures, soil moistures and leaf stages. Most of varieties studied in this experiment were very susceptible to the Phytopthora blight. Orotall, Suweon 7, Suweon 27 and Jochiweon were resistant to the disease. PI280795 and IS103 showed a tendency to be morderately resistant. The infected areas by Corynespora leaf blight were 15% in Kwangeui and 25% in Kimpo variety at high temperature condition of 3$0^{\circ}C$, respectively. The infection areas were 50% in Kwangeui and 70% in Kimpo variety at low temperature condition of 17$^{\circ}C$. These results indicate that the development of the leaf blight was highly increased at low temperature. The infection areas by the Corynespora were 55% in Kwangeui and 80% in Kimpo at wet soil moisture condition, and 10% in Kwageui and 15% in Kimpo at dry condition, respectively. The infection of the leaf blight was highly increased at 6 leaf stage and flowering date compared to at 10 and 20 leaf stages. The infection ratios were 20% at 6 leaf stage and 52.5% at flowering date, respectively.

• Current Research on Agriculture and Life Sciences
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• v.31 no.4
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• pp.245-249
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• 2013

In 2008, leaf blight symptoms were observed on several Chinese chive farms in Sangju. The Pathogenicity of the isolate was confirmed by artificial inoculation, where the pathogen exhibited a strong pathogenicity toward healthy plants. Morphological classification identified the isolate as from the Fusarium genus. For further analysis, PCR and phylogenetic classification were performed with ITS region and 28S rRNA gene which are commonly used for fungal identification. However, the results provided a poor resolution. To solve this problem, we analyzed translation elongation factor 1-alpha (TEF-$1{\alpha}$) gene. The analyzed results using TEF-$1{\alpha}$ gene indicated that the isolate was F. proliferatum. Therefore, it is assumed that TEF-$1{\alpha}$ gene is important when Fusarium sp. was identified using molecular classification method.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.5
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• pp.348-351
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• 2001

This study was conducted to evaluate the control effect of fungicides on control of brown leaf blight, growth characteristics, and dry root yield in the cultivation of Alisma plantago after early maturing rice cropping. All fungicides treated had no effect on the growth and flowering rate of Alisma plantago. The major fungicides were mancozeb Wp, 75%, chlorothalonil Wp, 75%, dithianon Wp, 43%, difenoconazole Wp, 10%, benomyl Wp, 50%, and propineb Wp, 70%. Dry root of yield were increased largely with chlorothalonil Wp, 75%(33 g/20), fungicide than the other fungicides and control. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the Alisma plantago.

• Journal of Ginseng Research
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• v.9 no.2
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• pp.163-169
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• 1985

The efficacy of fungicides was compared for control of root rot as well as leaf blight caused by Phytophthora cactorum on ginseng plants. Growth of P. cactorum in rlitro was completely or highly inhibited by metalaxyl, tetracyclin, captafol, carbendazim, and thiophanate + thiram. In field trials, the disease was significantly reduced not only in the root rot but also in the leaf blight when metalaxyl was applied at 4.17 mg a.i. per plant for soil drenching and 1.25 mg a.i. for foliage application. Also captafol was effective on control of the leaf blight but its effect was inferior to that of metalaxyl. Metalaxyl lost its effectiveness in vivo between the 5th and 7th week after soil wren ching. Phytotoxicity was, however, observed on 2 years old ginseng plants when metalaxyl was drenched at 8 mg a.i. while no phytotoxic symptom was developed on 2 years old ginseng plants at 4k mg a.i. and 3 years old at 16 mg a.i. per plant, respectively.

• Plant Resources
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• v.8 no.2
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• pp.161-166
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• 2005

This study was conducted evaluate the control effect of fungicides on control of Leaf blight, growth characteristics, and dry yield in the cultivation of Job's tears. All fungicides treated had no effect on the growth of Job's tears. The major fungicides were mancozeb Wp, $75\%$, chlorothalonil Wp, $75\%$, dithianon Wp, $43\%$, difenoconazole Wp, $10\%$, benomyl Wp, $50\%$, and propineb Wp, $70\%$. Dry seed yield were increased largely with chlorothalonil Wp, $75\%\;(33g/20\ell)$, fungicide than the other fungicides and control. All fungicides had no injury with standard dosage. On the other hand all fungicides had slight injury in the double dosage level for the Job's tears.

• Korean Journal Plant Pathology
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• v.14 no.2
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• pp.120-124
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• 1998

The conidial germination of Pestaotiopsis theae was occurred in cells attched with pedicels, the inferior cell of conidium. The cells were swollen like a ball, and then germinated in 4 hours under favorable conditions. Generally, it was considered that fifty percent of whole conidia was germinated in the range 6~12 hours. The optimum temperature and pH for conidial germination of P. theae (SP-3) causing leaf blight on sweet persimmon was $25^{\circ}C$ and pH 5, respectively. Conidial germination rate was higher than 90% at 100% relative humidity, but never germinated at a relative humidity lower than 88.5%. Conidial germination was highest at the concentration of 1~4$\times$104 conidia/ml. In case of cultural media, the conidial germination was higher than 90% on PDA, PSA, OME and Leonian agar. There was no relationship between light and conidial germination. It was concluded that the key environmental factors affecting conidial germination of the fungus (SP-3) were temperature and moisture.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.128.1-128
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• 2003

A leaf blight disease was found on Fatsia japonica plants growing in the first author's apartment garden in May, 2003. Major symptoms were leaf blight and petiole rot. A species of Phytophthora was isolated from the lesions. The isolate readily produced sporangia and sex organs on V8 juice agar plates. Sporangia were papillate, ovoid to subspherical and caducous with a pedicel. Sporangia were 33.6-38.4 ${\times}$ 33.6$\mu\textrm{m}$ with 1/b ratio approximately 1.14, papillae 4-5$\mu\textrm{m}$ high, pedicels also 4-5$\mu\textrm{m}$ long. Oogonia were spherical, 28.8$\mu\textrm{m}$ in diameter. Antheridia were globose, 14.4$\mu\textrm{m}$ in diameter and mating with oogonia paragynously. Mycelia grew best at 30$^{\circ}C$ and did not grow at 35$^{\circ}C$ or above, and at 5$^{\circ}C$. The morphological characteristics conformed to P. cactorum (Leb. And Cohn) Schroeter.

• Journal of agriculture & life science
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• v.50 no.4
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• pp.249-253
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• 2016

Aster glehni Franchet et Schmidt is a compositae plant and has been known as a native specie in Ulleung Island, Korea. It is officially recognized as a regional specialty that grows only in this region. In 2014, brown and dark spots were observed on aster leaves in a forest research field, Jinju, Korea. A causal agent was isolated from the disease symptomatic leaves and identified as fungus Alternaria solani. Fungal morphological characteristics and molecular identification with internal transcribed spacer sequences were synchronized as A. solani. The isolated fungi reproduced the same disease symptoms when the fungus was artificially inoculated on healthy aster leaves. This is the first report that A. solani caused leaf blight disease in Aster glehni in Korea.

• The Korean Journal of Mycology
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• v.51 no.3
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• pp.245-249
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• 2023

Prickly lettuce (Lactuca serriola), an invasive annual plant, poses a significant threat to the agricultural systems of many countries, including Korea. In 2020, leaf blight symptoms were observed in the prickly lettuce populations of various farms across Korea. Detailed morphological and molecular sequence analyses revealed that the disease was caused by the fungus, Curvularia intermedia. A pathogenicity test confirmed that the fungus can cause the same symptoms in healthy prickly lettuce, thereby fulfilling Koch's postulates. To the best of our knowledge, this is the first report of C. intermedia causing leaf blight on L. serriola in Korea, suggesting its potential as a biocontrol agent for this weed. However, further investigations are necessary to determine its ecological impact to prevent any non-target effects.