• The Plant Pathology Journal
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• 제37권3호
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• pp.258-267
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• 2021

Asian pear (Pyrus pyrifolia) is a widely cultivated and commercially important fruit crop, which is occasionally subject to severe economic losses due to latent viral infections. Thus, the aim of the present study was to examine and provide a comprehensive overview of virus populations infecting a major pear cultivar ('Singo') in Korea. From June 2017 to October 2019, leaf samples (n = 110) of pear trees from 35 orchards in five major pear-producing regions were collected and subjected to RNA sequencing. Most virus-associated contigs matched the sequences of known viruses, including apple stem grooving virus (ASGV) and apple stem pitting virus (ASPV). However, some contigs matched the sequences of apple green crinkle-associated virus and cucumber mosaic virus. In addition, three complete or nearly complete genomes were constructed based on transcriptome data and subjected to phylogenetic analyses. Based on the number of virus-associated reads, ASGV and ASPV were identified as the dominant viruses of 'Singo.' The present study describes the virome of a major pear cultivar in Korea, and looks into the diversity of viral communities in this cultivar. This study can provide valuable information on the complexity of genetic variability of viruses infecting pear trees.

• The Plant Pathology Journal
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• 제40권5호
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• pp.486-497
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• 2024

Mosaic is the most common viral disease affecting fig plants. Although the Fig mosaic virus is the leading cause of mosaic disease, other viruses are also involved. High-throughput sequencing was used to assess viral infections in fig plants with mosaic. The genomic DNA and total RNAseq of mosaic-symptomatic fig leaves were sequenced using the Illumina platform. The analysis revealed the presence of fig badnavirus 1 (FBV-1), grapevine badnavirus 1 (GBV-1), citrus exocortis viroid (CEVd), and apple dimple fruit viroid (ADFVd). The FBV-1 and GBV-1 sequences were 7,140 bp and 7,239 bp long, respectively. The two genomes encode one open reading frame containing five major protein domains. The viroids, CEVd and ADFVd, were 397 bp and 305 bp long. Phylogenetic analyses revealed a close relationship between FBV-1 and Iranian isolates of the same species, while GBV-1 was closely related to Russian grapevine badnavirus isolates (Tem64, Blu17, KDH48, and Pal9). CEVd was closely related to other Iraqi isolates, while ADFVd was strongly related to a Spanish isolate. A registered endogenous pararetrovirus, caulimovirus-Fca1, with a size of 7,556 bp, was found in the RNA transcripts with a low expression level. This integrant was also detected in the genomes of the two lines 'Horaishi' (a female line) and 'Caprifig 6085' (a male line). Phylogenetic analyses revealed that caulimovirus-Fca1 was distinct from two other clades of different endogenous virus genera.

• The Plant Pathology Journal
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• 제18권5호
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• pp.259-265
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• 2002

Apple mosaic virus (ApMV), a member of the genus Ilarvirus, was detected and isolated from diseased 'Fuji' apple (Malus domestica) in Korea. The coat protein (CP) genes of two ApMV strains, denoted as ApMV-Kl and ApMV-K2, were amplified by using the reverse transcription and polymerase chain reaction (RT-PCR) and were analyzed thereafter. The objectives were to define the molecular variability of genomic information of ApMV found in Korea and to develop virus-derived resistant gene source for making virus-resistant trans-genic apple. RT-PCR amplicons for the APMVS were cloned and their nucleotide sequences were determined. The CPs of ApMV-Kl and ApMV-K2 consisted of 222 and 232 amino acid residues, respectively. The identities of the CPs of the two Korean APMVS were 93.1% and 85.6% at the nucleotide and amino acid sequences, respectively. The CP of ApMV-Kl showed 46.1-100% and 43.2-100% identities to eight different ApMV strains at the nucleotide and amino acid levels, respectively. When ApMV-PV32 strain was not included in the analysis, ApMV strains shared over 83.0% and 78.6% homologies at the nucleotide and amino acid levels, respectively. ApMV strains showed heterogeneity in CP size and sequence variability. Most of the amino acid residue differences were located at the N-termini of the strains of ApMV, whereas, the middle regions and C-termini were remarkably conserved. The APMVS were 17.(1-54.5% identical with three other species of the genus Ilarviyus. ApMV strains can be classified into three subgroups (subgroups I, II, and III) based on the phylogenetic analysis of CP gene in both nucleotide and amino acid levels. Interestingly, all the strains of subgroup I were isolated from apple plants, while the strains of subgroups II and III were originated from peach, hop, or pear, The results suggest that ApMV strains co-evolved with their host plants, which may have resulted in the CP heterogeneity.

• 식물병연구
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• 제23권4호
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• pp.355-362
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• 2017

국내에서 유통되고 있는 사과나무 묘목의 바이러스 감염 실태를 파악하기 위하여 사과 '홍로'와 '후지' 및 '후지' 아조변이 품종을 구입하여 5종류의 바이러스에 대한 감염 여부를 검정하였다. 그 결과, '홍로' 품종의 접수 부위는 ACLSV, ASPV 및 ASGV에 각각 100%, 81.3% 및 100%의 감염률을 보였고 ApMV와 ASSVd에는 전혀 감염되지 않았다. '홍로' 품종의 대목 부위에 대하여, ACLSV, ASPV 및 ASGV의 감염률은 각각 87.5%, 81.3% 및 100%이었고 ApMV와 ASSVd의 감염률은 각각 12.5% 및 6.3%이었다. '후지' 품종 및 '후지' 아조변이 품종의 접수 부위는 ACLSV, ASPV 및 ASGV에 각각 86.7%, 86.7% 및 100%의 감염률을 보였고 ApMV와 ASSVd에는 전혀 감염되지 않았다. 대목 부위는 ACLSV, ASPV 및 ASGV에 각각 86.7%, 93.3% 및 93.3%의 감염률을 보였고 ApMV와 ASSVd에 대한 감염률은 각각 12.5%와 6.3%이었다.

• 식물병연구
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• 제20권4호
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• pp.307-313
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• 2014

2013년 5월, 경기도 수원시에서 모자이크와 기형의 병징을 보이는 천사의 나팔꽃 잎을 채집하였다. 채집한 시료는 전자현미경을 이용하여 검경한 결과 720-800 nm 길이의 사상형 입자가 관찰되었다. 전자현미경 검경 결과에 근거하여 기보고된 3종의 바이러스(Brugmansia mosaic virus, Colombian datura virus, Brugmansia suaveolens mottle virus)에 대하여 RT-PCR을 수행하였으며, BruMV에 양성반응을 보였다. 기계적 접종을 이용하여 BruMV의 병원성과 기주범위를 결정하였다. 가지과(담배, 토마토, 가지)와 비름과(땅꽈리)에서 전형적인 바이러스 병징이 나타났다. BruMV의 외피단백질을 결정하기 위하여 특이적 프라이머를 설계하였고, PCR, 클로닝, 시퀀싱을 수행하였다. 계통수 분석 결과, BruMV-SW는 BruMV SK와 가장 유사한 것으로 나타났다. 외피단백질을 이용한 뉴클레오타이드 상동성 비교에서는 BruMV 분리주와 92%와 99%의 상동성을 보였다.

• 농업과학연구
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• 제49권4호
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• pp.873-883
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• 2022

American plum line pattern virus (APLPV), a member of the genus Ilarvirus in the family Bromoviridae, is one of the plant quarantine pathogens in Korea. In this study, 15 candidate primer sets were designed and examined to develop a reverse transcription polymerase chain reaction (RT-PCR) assay for plant quarantine inspection of APLPV. Using APLPV-infected and healthy samples, the primer sets were assessed for APLPV detection. To confirm the occurrence of nonspecific reactions, six ilarviruses (Apple mosaic virus, Asparagus virus 2, Blueberry shock virus, Prune dwarf virus, Prunus necrotic ringspot virus, and Tobacco streak virus) and 10 target plants (Prunus mume, P. yedoensis, P. persica, P. armeniaca, P. dulcis, P. tomentosa, P. avium, P. glandulosa, P. salicina, and P. cerasifera) were examined. Finally, two primer sets were selected. These primer sets could generate the expected amplicons even with at least 1 ng of the total RNA template in concentration-dependent amplifications. In addition, a positive clone was developed for use as a positive control in the abovementioned RT-PCR assay.

• 식물병연구
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• 제23권1호
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• pp.75-81
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• 2017

2016년 5월, 우리나라 복숭아의 주요산지인 경북 영천 지역에서 퇴록, 괴저반점, 엽맥퇴록, 황화와 같은 바이러스 병징과 이상증상을 보이는 복숭아 잎 24점을 채집하였다. 이 시료들의 바이러스 감염 여부를 확인하기 위해 RT-PCR 진단법을 이용하여 진단하였다. 진단 대상은 검역 병원체로 지정된 바이러스 또는 바이로이드를 중심으로, 국내외 연구를 참고하여 국내 발생가능성이 높거나 발생 시 위험도가 높은 종 17종이다. 진단결과, 국내에서 보고된 적이 없는 바이러스 1종(Apricot pseudo-chlorotic leaf spot virus, APCLSV)과 검역 바이로이드 1종(Peach latent mosaic viroid, PLMVd)을 포함하여, 총 7종의 바이러스와 바이로이드가 검출되었다. 바이러스를 동정하기 위해, RT-PCR 산물을 sequencing 하여 확인하였다. 또, 국내 미보고 종인 APCLSV가 검출된 시료를 이용하여 APCLSV의 외피단백질을 암호화하고 있는 염기서열을 증폭하여 결정하였다. 결정된 염기서열은 기 보고된 APCLSV 분리주와 97%의 상동성을 보였다. 이 외피단백질 염기서열을 Trichovirus속 바이러스들과 비교 분석하여, 최종적으로 APCLSV임을 확인하였다. 동정된 APCLSV를 Yeongcheon 분리주로 명명하고 결정된 외피단백질 염기서열은 NCBI GenBank에 등록하였다. APCLSV의 발생 양상을 보면, APCLSV가 검출된 시료들은 모두 Apple chlorotic leaf spot virus (ACLSV)가 복합감염되어 있었으며, APCLSV는 ACLSV와 유전학적 유연관계가 가까운 것으로 알려져 있다. ACLSV의 특성에 비추어 볼 때, APCLSV는 국내 과수 농가에 널리 퍼질 가능성이 높을 것으로 생각된다. 따라서, 추후 국내 농가에 미칠 영향 등에 관련된 연구가 필요하다.

• The Plant Pathology Journal
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• 제33권6호
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• pp.608-613
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• 2017

The full-length sequence of a new isolate of Apple chlorotic leaf spot virus (ACLSV) from Korea was divergent, but most closely related to the Japanese isolate A4, at 84% nucleotide identity. The full-length cDNA of the Korean isolate of ACLSV was cloned into a binary vector downstream of the bacteriophage T7 RNA promoter and the Cauliflower mosaic virus 35S promoter. Chenopodium quinoa was successfully infected using in vitro transcripts synthesized using the T7 promoter, detected at 20 days post inoculation (dpi), but did not produce obvious symptoms. Nicotiana occidentalis and C. quinoa were inoculated through agroinfiltration. At 32 dpi the infection rate was evaluated; no C. quinoa plants were infected by agroinfiltration, but infection of N. occidentalis was obtained.

• 식물병연구
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• 제18권4호
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• pp.391-395
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• 2012

국내에서 재배되는 복숭아에 발생하는 바이러스병을 조사하기 위하여 경북 영천 등 복숭아 주산단지 6개 지역에서 전체 시료 515점을 채집하여 5종(ACLSV, ApMV, PDV, PNRSV, PPV) 바이러스의 감염여부를 RT-PCR 방법을 이용하여 바이러스 검정을 실시하였다. RT-PCR 검정 결과 전체 시료 515점 중 335점의 시료에서 ACLSV와 PNRSV가 검출되어 검정한 시료의 65.0%가 바이러스에 감염된 것을 확인하였다. ACLSV가 검출된 복숭아나무는 잎에 모자이크 증상이 관찰되었으며 PNRSV가 검출된 복숭아나무는 별다른 이상증상이 관찰되지 않았다. 검출된 바이러스의 유전자 염기서열 분석으로 ACLSV 4개와 PNRSV 3개의 분리주들을 확인하였으며 ACLSV 분리주들 간에는 95% 이상, PNRSV는 88% 이상의 아미노산 서열 상동성을 나타냈다. 기존에 보고된 ACLSV 및 PNRSV 분리주들과의 아미노산 서열 비교에서는 ACLSV 분리주들의 경우 70-99%, PNRSV 분리주들의 경우 88-99%의 상동성을 보였다. 이들 바이러스 분리주들의 계통학적 분석에서 ACLSV 분리주들은 A, B 그룹 중 A그룹에, PNRSV 분리주들은 I (PV32), II (PV96), III (PE5) 그룹에 각각 하나씩 속하는 것으로 나타났다.

• The Plant Pathology Journal
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• 제27권1호
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• pp.44-52
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• 2011

Field surveys were conducted in 45 stone fruit orchards in seven districts of Isparta Province located in western Mediterranean region of Turkey important for stone fruit production. Leaf samples were collected from 175 trees showing virus-like symptoms. These samples were first tested by ELISA for five different RNA viruses including Apple mosaic ilarvirus (ApMV), Prunus necrotic ringspot ilarvirus (PNRSV), Prune dwarf ilarvirus (PDV), Plum pox potyvirus (PPV), Apple chlorotic leafspot trichovirus (ACLSV). While no ApMV and PPV infection was found, 46, 24 and 16 samples were tested positive for PDV, ACLSV and PNRSV, respectively, in ELISA showing about 45% of symptomatic trees in the region were infected with at least one of these viruses. In addition, it was found that nine sweet cherry trees were mixed infected with two or three of these viruses and PDV with an infection rate of 26.3% was the most widespread virus in symptomatic trees in western Mediterranean region. Thirty samples were selected and tested by a multiplex RT-PCR (mRT-PCR) for simultaneous detection of these viruses. While PPV was not detected, more than half of the tested 20 samples were individually or mixed infected with ApMV, ACLSV, PNRSV and PDV. The mRT-PCR results were confirmed by detection of these viruses individually in some of the field samples using RT-PCR with primes specific to each virus. Comparison of ELSA and mRT-PCR results of 30 samples showed that numbers of infected and mixed infected samples as well as infection and mixed infection rates were significantly higher in RT-PCR (20 and 66.7%) than in ELISA (14 and 46.7%). The results confirm that mRT-PCR is more sensitive than ELISA.