• Research in Plant Disease
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• v.10 no.1
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• pp.17-20
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• 2004

A disease causing blights on leaves, stems, flowers, and pods of Vinca (Catharanthus roseus L.) was occurred in Aug. 2003 in Chengdo Peach Experiment Station. A species of Phytophthora was isolated from the diseased tissues. The causal fungus was identified as Phytophthora nicotianae on the basis of mycological characteristics and pathogenicity. Sporangia were ovoid to spherical, noncaducous, prominently papillate and averaged 38.0${\times}$31.0 ${\mu}{\textrm}{m}$ in dimension. Chlamydospores were abundantly produced on agar media and sized about 30.5 fm in diameter, The fungus was heterothallic and Al mating type. Oospores were measured 23.1 ${\mu}{\textrm}{m}$ in size. Optimum temperature for growth of the fungus was 25 to 3$0^{\circ}C$. This is the first report of occurrence of foliage blight of Vinca caused by P. nicotianae in Korea.

• Research in Plant Disease
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• v.9 no.1
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• pp.36-38
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• 2003

Stem blight of brunfelsia (Brunfelsia calycina) caused by Fusarium oxysporum was found in greenhouse around Sungnam area, Kyunggi province, Korea in September 2001. The initial infection appeared as a slight wilting of the foliage, turned yellow from the lower leaves. The yellowing leaves were falled, resulting in blight of stem and eventual death of the entire plant. The vascular tissue of a diseased plants became dark brown and browning of the vascular system was a characteristic of the disease and the pith remained healthy, Isolates obtained from the lesions of the diseased plant were identified as F. oxysporum, based on the morphological characteristics of conidia. Symptom by artificial inoculation was same to the symptom of naturally infected plants. This is the first report demonstrating the stem blight on a brunfelsia caused by F. oxysporum in Korea, and we proposed to name this disease "stem blight of brunfelsia".

• Mycobiology
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• v.45 no.3
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• pp.123-128
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• 2017

A severe leaf spot, turning to foliage blight, was observed on leaves of Maranta leuconeura growing in a garden in Brazil (state of Rio de Janeiro) in 2015. A dematiaceous hyphomycete bearing a morphology typical of a helminthosporoid fungi was regularly found in association with diseased tissues. The fungus was isolated and pathogenicity was demonstrated through the completion of Koch's postulates. A morphology and molecular analysis led to the conclusion that the fungus belonged to the genus Bipolaris, which is characterized by having fusiform conidia, externally thickened and truncate hila and a bipolar pattern of germination. Additionally, homology of internal transcribed spacer and GAPDH sequences with sequences of other Bipolaris species, confirmed its generic placement. A phylogenetic study also indicated clearly that the fungus on M. leuconeura is phylogenetically distinct from related species of this genus, leading to the proposal of the new species Bipolaris marantae.

• 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.

• Research in Plant Disease
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• v.19 no.3
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• pp.208-215
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• 2013

3-(4-Hydroxyphenyl)-propionic acid (HPP) is a bacterial metabolite synthesized and released by an entomopathogenic bacterium Xenorhabdus nematophila K1. In this study, the control efficacy of HPP was tested against Phytophthora blight and anthracnose of red pepper plants. HPP suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight condition, HPP maintained the antifungal activity on the diseases for at least twenty five days. The antifungal activity was not decreased even in the condition of soil-water. It was proved that HPP was able to penetrate the roots and travel upward of the red pepper plants. When HPP suspension was applied to soil rhizosphere before transplanting the red pepper seedlings or was regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight and anthracnose) without any phytotoxicity. These results suggested that HPP can be developed to a systemic agrochemical against Phytophthora blight and anthracnose of red pepper plants.

• Research in Plant Disease
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• v.18 no.1
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• pp.17-23
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• 2012

Indole compound is a bacterial metabolite synthesized and released by an entomopathogenic bacterium, Xenorhabdus nematophila K1. The antibiotic activity was evaluated against plant pathogens, such as Phytophthora blight and anthracnose of red pepper. Indole significantly suppressed mycelial growth of Phytophthora blight and anthracnose pathogens. Under natural sunlight conditions, indole maintained the antifungal activity for at least sixty days. The activity was not affected under the condition of soil-water. When the indole suspension was applied to surface soil before transplanting of red pepper seedlings and was then regularly sprayed to the foliage of the plants with ten days interval, it resulted in significant reduction of the disease occurrences (Phytophthora blight, anthracnose, soft rot, and black mold) by about 30%. These results suggest that indole can be used to control Phytophthora blight and anthracnose of red pepper.

• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.83-86
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• 1981

Experiments were carried out to study on control of stem blight of asparagas caused by Shoma asparagi Sacc. in Suweon, $1976\~1978$. Symptoms of the disease were found in the field from late of May and severe infection was shown thereafter. Plastic film mulching with foliage spray of Topsin 154g a.i. and Difolatan 220g a.i. per 10a at 10days interval during the growing season, gave significantly good control and high yield compared with other treatments. In addition to reduction of the disease, the treatment with mulching has maintained good soil moisture for asparagus growth when the soil moisture was measured at about loom under the soil surface from July to August.

• Korean Journal of Agricultural Science
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• v.7 no.2
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• pp.77-80
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• 1980

Alternaria longissima Deighton & Macgarvie was recorded for the first time on seeds of sesame in low percentages. Detailed descriptions of the habit characters, conidial morphology and cultural characters are described. This fungus, which is generally regarded as a saprophyte, was shown to be a pathogen to sesame plants producing zonate leaf spots, foliage blight, stem necrosis and spots on capsules, but does not show any pathogenicity to rice and sorghum plants.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.351-359
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• 1997

Antifungal activities of the crude extracts of Anemarrhena asphodeloides. Coptis japonica and Phellodendron amurense were tested against Phvtophthora capsici. and the control effect on red-pepper phytophthora hlight and phytotoxicities of red-pepper were investigated. The results were summarized as follows; Mycelial growth and zoosporangial germination of the red-peppcr phytophthora hlight organism P. capsici were inhihited hy thc crude extracts of plant materials. Methanol extracts or plant materials had hctter antifungal activity than water extracts at hoth a room temperature and a hoiling condition. Antifungal activities of three crude extracts were gradually decreased with prolonged storage period. Red-pepper phytophthora hlight was effectively controlled hy the crude extracts of three plant materials. Of these. the crude extract of C. japonica was marvelously effective. Phytotoxic symptom to red-pepper seedling showed hy water cultural method hut not by pot test. Seed germination and radicle growth of red-pepper were inhihited hy the crude extracts of three plant materials. Phytotoxic symptoms in the leaves and fruits of red-pepper were not ohserved with exogenous foliage application of the three crude extracts.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.61-67
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• 2009

"Early Valley", is an early maturing potato cultivar with high yield potential. "Early Valley" is a clonal selection resulting from the cross between 'Suncrisp' and 'A87109-10'. It has medium plant height and light green foliage. "Early Valley" has medium flowering habit and white flowers. Tubers are smooth, yellow skin, light yellow flesh, round tuber shape, medium eye depth, and medium dormancy and good keeping quality. It has stable yield under wide range of climatic conditions. "Early Valley" is resistance to late blight, but moderately susceptible to common scab and hollow heart. This cultivar is also resistant to potato rotting at harvesting during the raining season. "Early Valley" has high level of antioxidant activity (about three times higher) and vitamin C (higher by 40%) than the 'Superior'. This cultivar has high level of tuber uniformity and capable of yielding 36.56 t/ha which is 17.07% higher than the control potato cultivar 'Superior' under optimum agronomical practices.