• The Plant Pathology Journal
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• 제23권2호
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• pp.103-105
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• 2007

Mechanical transmission of barley seedlings with barley yellow mosaic virus (BaYMV) is generally inefficient and is the major constraint for testing cultivar resistance to the virus. To explore mechanical transmission, BaYMV-infected barley plants were grown at different conditions and used as inoculum sources to seedlings of susceptible barley cultivar Baegdong. Extracts prepared from BaYMV-infected Baegdong plants at 47, 53, 74, and 90 days after symptom appearance (DASA) and grown at 10 and $12^{\circ}C$ gave 10, 30, 68 and 76% infection, respectively on inoculated susceptible barley cv. Baegdong seedlings. While Jinyangbori, another susceptible cultivar obtained 95% infection rate inoculated with extracts from 90 DASA disease source and grown at $10/12^{\circ}C$. However, low infection rates were obtained when the virus sources were grown in a greenhouse at $15-18^{\circ}C$. Our results indicate that longer incubation period and lower temperature are required for virus accumulation and stability.

• The Plant Pathology Journal
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• 제22권4호
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• pp.329-333
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• 2006

Two distinct and stable isolates of Barley mild mosaic virus(BaMMV) designated as Naju82-S(severe) and Naju82-M(mild) were obtained. These two isolates differed in their symptomatology, virus transmission characteristics and cultivar specificity at various temperature. Thus, these isolates were referred to as strains in this study. BaMMV Naju-S strain showed severe mosaic symptoms accompanied by necrosis on the infected leaves. Naju82-S strain is more virulent demonstrated by shorter incubation period and relatively high virus concentration than Naju82-M strain. Five Korean cultivars were tested for their pathogenicity to different strains based on the rate of infection. Results showed that infection rate of cultivars to both strains did not significantly differed from each other. However, under different temperatures, the pathogenicity on the two cultivars such as cultivars Hopumbori and Sessalbori were significantly affected. Hopumbori was moderately resistant to both strains at $10-12^{\circ}C$ and susceptible at $15-18^{\circ}C$. Similarly, Sessalbori was moderately resistant at $10-12^{\circ}C$ to both strains but distinctly differentiated at $15-18^{\circ}C$ wherein it was resistant to mild strain and highly susceptible to severe strain. Other cultivars including Baegdong, Jinyangbori and Neahanssalbori consistently showed susceptible reaction to both strains at varying temperatures tested in this study.

• The Plant Pathology Journal
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• 제22권4호
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• pp.348-352
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• 2006

Barley mild mosaic virus(BaMMV) is a soilborne Bymovirus vectored by root-infecting fungus, Polymyxa graminis. Mechanism of cultivar's resistance to BaMMV in field tests are difficult to assess since resistance could be either due to the virus or to P. graminis, or both. Whereas, available mechanical inoculation methods for BaMMV and other related viruses are labor intensive, give inconsistent results and generally result in low infection rates. Inoculation method using stick with gauze(SWG) was developed for BaMMV. The improved method proved to be simple, efficient, and reliable. The infected leaf tissues were preserved by drying in a frozen state under high vaccum(freeze dried barley infected leaves) to circumvent reduction of virus infectivity during storage. Five Korean barley cultivars were mechanically inoculated with BaMMV-infected sap by the improved method. Infection rates obtained were compared with natural infection. Cultivar Naehanssalbori showed resistance to BaMMV in the field trials but was found highly susceptible in the greenhouse tests by mechanical inoculation, indicating that the field resistance may be possibly due to resistance to P. graminis.

• Plant Resources
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• 제1권2호
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• pp.92-97
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• 1998

An isolate of barley yellow mosaic virus(BaYMV-HN) obtained from Haenam, Korea was compared with two BaYMV strains. BaYMV-Ⅱ-1 from Japan and BaYMV-G from Germany. The sequence of the 3'-terminal 3817nucleotides[excluding the poly (A) tail] of RNA 1 of BaYMV-HN was determined to start within a long open reading frame coding for a part of the NIa-VPg polymerase(26 amino acids). NIa-Pro polymerase (343 amino acids), NIb polymerase(528 amino acids) and the entire capsid protein(297 amino acids), which is followed by a noncoding region(NCR) of 235 nucelotides. In the partial ORFs, BaYMV-HN shows higher sequence homology with BaYMV-Ⅱ-1(99.5%) than BaYMV-G(92.7%). The 3' non-coding regions of BaYMV-HN(235nt) shows higher nucleotide sequence homology with BaYMV-G(235nt)(99.6%) than BaYMV-Ⅱ-1(231nt)(97.0%). The 3' NIa-Pro protein sequence of BaYMV-HN shows higher amino acid sequence homology with BaYMV-Ⅱ-1(95.0%) than BaYMV-G(93.6%), but, NIb protein sequence of BaYMV-HN shows same all amino acid sequence. The capsid protein sequence of BaYMV-HN(297aa) shows same with BaYMV-Ⅱ-1, and shows higher nucleotide sequence homology with BaYMV-UK (from United Kingdom)(97.3%) than BaYMV-G(96.9%) and G2(96.9%). Difference of capsid protein amino acid were 0-9 between the Japan, United Kingdom and Germany and were 2-6 between all Korean isolates. Many of the amino acid differences are located in the N-terminal regions of the capsid proteins from 1 to 74 amino acid positions.

• The Plant Pathology Journal
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• 제23권4호
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• pp.260-265
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• 2007

Testing a large number of samples from field monitoring and routine indexing is cumbersome and the available virus detection tools were labor intensive and expensive. To circumvent these problems we established tissue blot immunoassay (TBIA) method an alternative detection tool to detect Barley mild mosaic virus (BaMMV) and Barley yellow mosaic virus (BaYMV) infection in the field and greenhouse inoculated plants for monitoring and routine indexing applications, respectively. Initially, leaf and stem were tested to determine suitable plant tissue for direct blotting on nitrocellulose membrane. The dilutions of antibodies were optimized for more efficient and economical purposes. Results showed that stem tissue was more suitable for direct blotting for it had no background that interferes in the reaction. Therefore, this technique was referred as direct stem blot immunoassay or DSBIA, in this study. Re-used diluted (1:1000) antiserum and conjugate up to 3 times with the addition of half strength amount of concentrated antibodies was more effective in detecting the virus. The virus blotted on the nitrocellulose membrane from stem tissues kept at room temperature for 3 days were still detectable. The efficiency of DSBIA and RT-PCR in detecting BaMMV and BaYMV were relatively comparable. Results further proved that DSBIA is a rapid, reliable and economical detection method suitable for monitoring BaMMV and BaYMV infection in the field and practical method in indexing large scale of barley materials for virus resistance screening.

• 식물병연구
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• 제16권2호
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• pp.115-120
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• 2010

보리바이러스 발생 상습 논에서 관행(벼+보리)과 콩+보리의 작부체계가 보리의 바이러스병 발생과 수량에 미치는 영향을 5개년간 조사하였고, 윤작과 바이러스 매개균(Polymyxa graminis)의 밀도 변화를 검정하였다. 보리 감염 바이러스 종류를 검정한 결과 Barley yellow mosaic virus(BaYMV)와 Barley mild mosaic virus(BaMMV)가 혼합감염 되어 나타났다. 발병정도는 관행에서는 4년차를 제외하고는 7~9로 조사되었다. 반면 콩+보리 연작이나 3년 동안 휴경한 경우는 발병정도가 7정도로 관행과 비슷한 결과를 보였다. 콩+벼 작부체계 중에서 보리를 1년 또는 2년(1년/2년) 휴경하면서 콩을 재배한 경우 발병정도가 중 정도(5)로 감소하는 결과를 보였다. 작부형태에 따른 BaYMV와 BaMMV의 매개균인 P. graminis의 보리 뿌리와 토양 중 밀도 변화를 조사하였다. 보리를 1년 휴경한 처리에서 보리 뿌리와 토양 중 매개균의 밀도가 가장 낮아졌다. 콩을 재배하면서 보리를 1년 휴경한 처리에서 5년차에는 관행에 비해 초장은 비슷하였으나, 경수는 158개/$m^2$ 많아 생육이 좋은 결과를 보였다. 콩과 보리를 연작하거나 3년간 보리와 콩을 재배하지 않고 휴경한 경우에는 관행에 비해 초장이나 경수 등 생육이 저조한 결과를 보였다. 수확기에 간장 등 수량 구성요소가 관행에 비해 보리+콩의 윤작처리에서 좋은 경향을 보여 콩과의 윤작 처리가 수량에도 영향을 미친 것으로 나타났다. 간장은 보리를 1년/2년 휴경한 처리에서 5년차에 관행과 보리+콩 연작 처리에 비해 1.3~2.8 cm 컸고, 수수도 36~90개/$m^2$ 많게 조사되었다. 그러나 콩+보리 연작이나 3년간 휴경한 처리에서는 관행에 비해 낮게 조사되었다. 수량성에서도 보리를 1년/2년 휴경한 처리에서는 3년차, 4년차, 5년차에서 모두 관행에 비해 수량이 많아지는 결과를 보였다.

• 식물병연구
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• 제16권1호
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• pp.21-26
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• 2010

우리나라에서 가장 우점하는 BaYMV(Barley yellow mosaic virus)에 의한 국내 육성 맥주보리의 품종의 저항성 정도에 따룬 생육 및 수량 피해를 조사하였다. 바이러스 감염 검정에서 두산 29호는 BaYMV와 BaMMV(Barley mild mosaic virus)에 감염되어 있었으나 진양보리와 호훔보리는 BaYMV에 만 감염된 것으로 나타났다. 월동후 초장과 수확기 간징의 생육을 조사한 결과 폼종별 저항성 정도에 따라 8~29%의 신장 억제율을 보였다. 생육 후기의 간장 단축률은 9~12%로 낮아지는 결과를 보였다. 월동후 경수는 호품에서는 발병포장와 건전포장에서 차이가 없었으나， 감수성인 두산 29호와 진양에서는 10~14%감소되었다. 그러나 수확기경 수수는 BaYMV 감염에 의해 26~33%까지 감소하는 결과를 보였다. 출수기는 발병 포장에서 1~3일까지 지연되는 경향이었다. 수확후 수량구성요소의 피해정도를 조사하였다. 천립중과 l 중도 품종별 저항성 정도에 따라 피해를 받아 각각 4.0~6.6%와1.0~ 4.2% 감소되는 것으로 조사되었다. BaYMV 감염시 6.0~8.6% 정 도의 비립이 발생하였으나 건정포장에서는 2.9~3.6%로 감소되어 두배 이상 비립발생이 증가하였다. 품종간 종실 수량 피해를 조사한 결과 건전한 포장에서의 품종간 평균 수량은 약 509kg~632kg/10a으로 유의성 있는 차이를 보이지 않았다. 발병 포장에서는 품종별 저항성 정도에 따라 유의성 있는 차이를 보였다. 중저항성인 호품의 경우 약 467kg/10a, 중약과 감수성인 진양과 두산29호에서는 각각 390kg과 290kg으로 조사되어 감수성인 두 품종에서는 77~177kg/10a의 수량 감소를 보였다. BaYMV 감염에 의해 수량성은 품종의 저항성 정도에 따라 26~43%의 감소되었다.