• 한국응용곤충학회지
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• 제16권4호
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• pp.209-210
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• 1977

Early in the growing season of 1976, rain and cool weather favored the blighting of leaves of young plants of barley by Fusarium nivale. The fungus was recovered in culture from infected foliage, and the perithecia of Calonectria nivalis were demonstrated to be present as well as the Fusarium state. On 22 April 1976, in Suweon, plants pulled at random revealed stem lesions from which F. nivale was cultured. On S May 1976 near Kwangju. Perithecia were found embedded within leaf sheaths and blades of mature wheat and barley plants. It was evident in the 1976, 1977 season that Fusarium(Calonectria) nivale was common but unrecognized as an early season pathogen of barley in Korea. The probable source of primary inoculum was the infected refuse from the previous season's barlry and wheat crops. Stem lesions caused by this fungus were considered to he detrimental to the maximum yield of barley or wheat.

• 한국식물병리학회지
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• 제14권3호
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• pp.247-252
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• 1998

A series of greenhouse test was conducted to evaluate infection of Calonectria ilicicola on soybean plants of different ages at time of inoculation. Lesion length and number of perithecia were determined on cultivars Braxton, Deltapine 726, and Riverside 699 that were 10∼40 days old and 4-10 days old at time of inoculation. Quadratic and linear relationships were described between plant age at inoculation and lesion length or perithecia production in greenhouse studies. Soybean seedlings exhibited low susceptibility to C. ilicicola regardless of cultivar susceptibility. On 8- or 1-0-days-old Braxton, lesion lenght and perithecia numbers were reduced. Lesion lengths were longest on plants 30 days old whereas perithecia production was greatest on plants 20∼30 days old at time of inoculation. Differences in lesion length and perithecia production that were observed on young plants (4∼10 days old) were similar to relative levels of susceptibility in soybean cultivars in greenhouse and field tests, suggesting that reaction to C. ilicicola in soybean cultivars may be determined early in plant development.

• 한국균학회지
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• 제8권1호
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• pp.53-57
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• 1980

An undescribed black root rot of soybean, caused by Cylindrocladium crotalariae, was observed in Suweon area. The diseased plants showed yellowing at the top and dry rot at the root. Lesions of roots and stems in the soil were red to brown and main roots were cracked. Although not observed the disease in the field, leaves of inoculated test plants in the greenhouse exhibited circular, brown lesion surrounded by chloratic halos. The fungus was recovered in culture from the infected stem and root, and the perithecia of Calonectria crotalariae were demonstrated to be present as well as the cylindrocladium state. The fungus was pathogenic to the root, stem, petioles and leaves of soybean. The probable source of primary inoculum was microsclerotia formed in infected soybean root and stem from the previous season's soybean debris. Black root rot by this fungus was considered to be one of detrimental factors to the maximum yield of soybean. From the morphological and physiological characteristics and pathogenic behaviors, this fungus was identified as Cylindrocladium(Calonectria) crotalariae.

• 한국응용곤충학회지
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• 제16권2호
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• pp.115-119
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• 1977

Fusarium spp가 1976년 포장에서 채집한 벼밀 보리에서 분리되었다. 병원성이 있는 것은 Fuarium(Calonectria) nivale, F.(Gibberella) moniliforme와 F.(Gibberella) roseum 'Graminearum'과 'Avenaceum'이었다. 부생균가운데 F.(Nectria) episphaeria가 분리되었다. F. nivale와 F. episphaeria의 완전시대인 Calonectria Nectria가 발견되었고 이것들은 한국에서 보고되지 않은 것으로 보인다. 분리된 Fusaria는 벼에서 $66.3\%$가 F. moniliforme 이고 보리, 밀에서$68.2\%$가 F. roseum 'Graminearum 이었다. 자낭각은 실험실 조건하에서 형성되었고 F. moniliforme는 밀이삭, 보리씨에 접종한 결과 병원성이 나타났다.

• 한국식물병리학회지
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• 제14권6호
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• pp.571-577
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• 1998

Variability in virulence of Calonectria ilicicola isolates form different hosts and geographic origin provides important information for breeding cultivars resistant to red crown rot. A wide range in virulence for 25 isolates of C. ilicicola from soybean and peanut was observed on six soybean cultivars. Soybean isolates were pathogenic on soybean although some were less virulent. Virulence of isolates was not affected greatly by cultivar and relatively consistent regardless of virulence level. Soybean isolates were more virulent on soybean than were peanut isolates. When virulence of two soybean and tow peanut isolates was compared between laboratory and greenhouse tests, it was stable across a range of cultivars. Mycelial growth of isolates from either soybean or peanut was reduced significantly on potato dextrose chlorate showed significant reduction of fungal growth than isolates from peanut did although their growth on potato dextrose agar was not significantly different. Evidence for physiologic specialization was not recognized in this system. However, the findings that soybean isolates of C. ilicicola were more virulent on soybean and reduction of fungal growth on potato dextrose chlorate than were peanut isolates suggest that host specialization may exist in this fugus.

• 한국균학회지
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• 제26권3호통권86호
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• pp.387-395
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• 1998

여러가지 기주에서 유쾌한 Calonectria ilicicola 균주의 병원성에 대한 형태적, 유전적 표지를 검출하기 위하여 균사생장, 균핵, 자낭각 그리고 dsRNA를 조사하였다. 시험된 모든 균주에서 병원성, 균핵수, 자낭각수 와 균사생장 등의 다양한 변이가 관찰되었으나 dsRNA는 검출되지 않았다. 균의 병원성은 균핵과 자낭각 생산과 각각 정의 상관관계가 있었으나, 균사 생장은 자낭각의 생산과 부의 상관관계를 보여 주었다. 땅콩에서 유래한 균주보다 콩에서 유래한 균주가 기주인 콩에 더 강한 병원성을 보였으며 균핵과 자낭각의 생산도 더 많았다. 이와 같은 결과로 볼 때 C. ilicicla의 균핵과 자낭각 생산력은 inoculum potential의 구성요소로써 작용하며, 이중 균의 자낭각 생산력은 병원성과 기주 분화를 나타내는데 유용한 표지로써 이용될 수 있을 것이다.

• Mycobiology
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• 제48권1호
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• pp.44-50
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• 2020

Calonectria pseudonaviculata and C. henricotiae are two closely related fungal species responsible for boxwood blight disease of ornamental shrubs (Buxus spp.) in the U.S. and Europe. A previous study has shown isolates of the latter species, which is restricted to Europe, to be less sensitive to tetraconazole, an azole fungicide. In this study, we have analyzed the CYP51 paralogs for polymorphism in 26 genomes, representing geographically disparate populations of C. pseudonaviculata (n = 19) and C. henricotiae (n = 7), from the U.S., Europe, Asia, and New Zealand. The presence of a CYP51A pseudogene and lack of a functional CYP51A paralog in all C. pseudonaviculata genomes examined is a novel discovery for fungi and could have implications for the evolution of resistance to antifungal chemicals.

• Mycobiology
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• 제38권4호
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• pp.339-342
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• 2010

Basal stem rot symptoms were found on blueberry seedlings imported from the United States of America in 2008. The fungus obtained from the diseased seedlings was identified as Calonectria colhounii based on morphological and molecular characteristics. The consignments of the blueberry seedlings infected with C. colhounii were destroyed to prevent introduction of the fungus to Korea.

• 한국작물학회지
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• 제43권4호
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• pp.239-244
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• 1998

Susceptibility of soybean cultivars to Calonectria illicicola was evaluated in a greenhouse by inoculating seedlings with mycelium in agar discs placed on the stems at the soil line. A range of responses was detected among cultivars following inoculation with a virulent isolate of C.ilicicola. Rankings of cultivars between greenhouse tests 1 and 2 were similar for disease severity and areas under the disease progress curves (AUDPC). In addition, rankings of cultivars for Final disease severity were highly correlated with AUDPC in test 1 ($r_s$ =0.88, t =5.48, p<0.001), test 2 ($r_s$ =0.99, t =22.10, p<0.001), and when tests were combined ($r_s$=0.89, t=5.82, p<0. 001). Final disease severity and AUDPC consistently identified Asgrow 7986, Braxton, Cajun, and Forrest as soybean cultivars least susceptible to red crown rot. In 1993 and 1994 field tests, a range in disease susceptibility was observed for tested cultivars but none was completely resistant. Soybean cultivars Braxton, Cajun, and Forrest, which were least susceptible to red crown rot in greenhouse tests, also ranked among cultivars with the lowest disease incidence and AUDPC in field tests. Comparisons .between rankings of the eight cultivars common to greenhouse and field tests showed a correlation between final disease severity from combined greenhouse tests and both final disease incidence ($r_s$=0.63, t =1.99, p<0.1) and AUDPC ($r_s$=0.60, t =1.82, p < 0.2) from the combined field tests. However, AUDPC from greenhouse tests did not correlate with either final disease incidence or AUDPC from field tests. The green-house screening method provided consistent results between greenhouse and field tests and successfully identified the least susceptible cultivars Braxton, Cajun, and Forrest.

• 한국응용곤충학회지
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• 제19권4호
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• pp.228-233
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• 1980

The infection rate of soybean black root rot disease caused by Calonectria crotalariae was about $14\%$. The isolated fungi from the infected soybean roots and stems were Calonectria crotalariae, Fusarium solani, F. roseum, Phomopsis sojae, Pythium aphanidermatum, Rhizoctonia solani and Macrophomina sp. Among them, C. crotalariae was the most virulent pathogen under the laboratory conditions. Mycelial growth and microsclerotial formation were good on PSA containing 1000cc of water, 100g of potato and 20g of sugar. Mycelial growth, sporulation and microsclerotial formation were good on sterilized root. Perithecial formation was better in the dark condition than in the light. Survival of macroconidia was not available between $0\~25\%$ soil water content. Microsclerotia and mycelium in infected plant debris were survived for 4 months at to $8\%\;50\%$ soil water content. The plant height, when inoculated with $1.2\%$ inoculum density, reached approximately half of uninoculated plants. Disease severity was much higher at nonsterilized soil than completely sterilized soil. It was determined that the host range of this pathogen includes soybean, peanut, green bean and red bean.