• 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.

• 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.

• 식물병연구
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• 제12권3호
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• pp.178-184
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• 2006

2002년과 2003년 중부 이남의 콩 재배지에서 지상부에 황화 증상을 보이며, 지제부에 붉은 색의 자낭각이 형성된 콩을 채집하여 검은뿌리썩음병균을 분리하였다. 분리한 병원균으로부터 유성세대의 자낭각, 자낭, 자낭포자를, 무성세대의 분생포자와 소낭을 관찰하였다. 자낭각의 크기는 $357.9(312.5{\sim}391.5.7){\times}474.3(419{\sim}535){\mu}m$로 적갈색의 구형 또는 난형이었으며, 자낭(크기: $90.9{\times}15.0{\mu}m$)은 무색투명한 곤봉상의 모양을 나타내고 있었다. 자낭안에 8개의 자낭포자가 형성되었는데, 무색투명하며 1-3개의 격벽을 지닌 약간 굽은 긴 형태로 크기는 $36.87(31.1{\sim}49.4){\times}5.22(4.5{\sim}6.1){\mu}m$이었다. 무성생식세대에서 만드는 분생포자는 긴 원통형이며 색깔은 투명하고, 크기는 $73.24(68.1{\sim}77.6){\times}5.76(4.9{\sim}6.8){\mu}m$로 자낭포자보다 컸다. 소낭의 모양은 둥근 모양이며 크기는 지름이 $8.46(6.2{\sim}10.0){\mu}m$로 관찰되었으며, 이는 Crous의 결과와 일치하였다. ITS와 $\beta$-tubuline 유전자의 염기서열을 조사하여 phylogenetic analysis를 수행한 결과, 국내에서 분리한 18개의 병원균과 일본에서 분양받은 10개의 병원균 모두 Cylindrocladium parasiticum으로 동정되었다.