• Journal of Microbiology and Biotechnology
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• 제29권5호
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• pp.785-793
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• 2019

Black rot caused by Xanthomonas campestris pv. campestris (Xcc) is the most damaging disease in Brassica crops around the world. In this study, we developed a molecular marker specific to Xcc race 5. To do this, the available whole genome sequences of Xcc races/strains and Xc subspecies were aligned and identified a highly variable genomic region (XccR5-89.2). Subsequently, a primer set covering the 'XccR5-89.2' region was designed and tested against the genomic DNA of Xcc races/strains, Xc subspecies and other plant-infecting bacterial strains (Pseudomonas syringae pv. maculicola and Erwinia carotovora subsp. carotovora). The results showed that the 'XccR5-89.2' primer pair amplified a 2,172-bp fragment specific to Xcc race 5. Moreover, they also amplified a 1,515-bp fragment for Xcc race 1 and an over 3,000-bp fragment for Xcc race 3. However, they did not amplify any fragments from the remaining Xcc races/strains, subspecies or other bacterial strains. The 'XccR5-89.2' primer pair was further PCR amplified from race-unknown Xcc strains and ICMP8 was identified as race 5 among nine race-unknown Xcc strains. Further cloning and sequencing of the bands amplified from race 5 and ICMP8 with 'XccR5-89.2' primers revealed both carrying identical sequences. The results showed that the 'XccR5-89.2' marker can effectively and proficiently detect, and identify Xcc race 5 from Xcc races/strains, subspecies and other plant-infecting bacteria. To our knowledge, this is the first report for an Xcc race 5-specific molecular marker.

• 한국식물병리학회지
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• 제1권1호
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• pp.61-66
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• 1985

벼 흰빛잎마름병균주 Q7472와 Q7502의 항혈청을 사용하여 우리나라에서 수집한 벼 흰빛잎마름병균의 혈청형을 한천gel내 확산법에 의해 분류한 결과, 71균주중 65균주가 혈정형 A형, 5균주가 B-I, 1균주가 B-II형에 속하였다. 혈청형A에 속하는 균주는 $0.1-1\%$의 $CaCl_2$용액에서 자기의집이 거의 일어나지 않았으나 혈청형 B-I과 B-II에 속하는 균주는 심한 자기의집이 일어나 혈청형과 자기의집 사이에는 밀접한 관계가 있었다. 흰빛잎마름병균은 혈청학적 방법에 의해 쉽게 검색될 뿐만 아니라 한천gel내 확산법에 의해 벼 세균성줄무늬병균인 X.campestris pv. olyzicola의 부생세균인 E. herbicola와도 쉽게 구별되었다. 흰빛잎마름병균 검출은 병반을 NaCl용액에 넣은 후에 착압하거나 $100^{\circ}C$에서 1시간 열처리 후 착압한 즙액을 한천gel내 확산법에 의해 항혈청과 반응시킴으로써 가능하였으며, 병반이 적을때는 PSA배지에서 배양한 후 사용하면 효과적이었다.

• Journal of Plant Biotechnology
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• 제32권4호
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• pp.275-279
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• 2005

Brassica campestris var. narinosa는 새싹채소로 애용되는 식물로서 간단한 용기에서 손쉽게 재배할 수 있다. 본 연구에서는 vacuum-infiltration을 통한 Agrobacterium-mediated transformation에 의해서 B. campestris var. narinosa 싹에서의 GUS일시발현을 성공적으로 확인하였다. 발아전의 종자가 발아를 이미 시작한 종자보다 그 형질전환 효율이 높게 나타났다. 한편, hydrogen peroxide를 2일 생장시킨 싹에 처리한 후 형질전환 하였을 때 GUS발현이 증가되는 것을 관찰하였다. 간염항원유전자의 형질전환과 ELISA에 의한 항원단백질의 발현량 분석 시 hydrogen peroxide 처리 싹이 비처리 형질전환 싹에서 보다 2배 이상의 발현량이 측정되었다.

• 한국식물병리학회지
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• 제13권1호
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• pp.5-12
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• 1997

Genetic diversity of forty-four strains of Xanthomonas campestris pv. vesicatoria from diverse geographic origins was investigated using random amplified polymorphic DNA (RAPD) of genomic DNA. One hundred and thirty-seven amplified fragments were produced by polymerase chain reaction with a set of 14 random primers, and the sizes of amplified DNA fragments ranged approximately from 0.3 to 3.2 kb. Cluster analysis of genetic similarity among the strains generated the dendrogram that clearly separated all strains from each other. The 44 strains of X. campestris pv. vesicatoria were classified into 4 major genomic DNA RAPD groups and 15 subgroups at the genetic similarity of 0.60 and 0.92, respectively. The strains from foreign countries formed discrete subgroups, but the United States strain 87-77 clustered closely with some of Korean strains together. Thirty-nine Korean strains were classified into 11 subgroups, and especially Masan strain Ms93-1 clustered distinctly far from the other Korean strains. RAPD polymorphism suggests strongly the occurrence of genetic differentiation of X. campestris pv. vesicatoria and the existence of genetically distinctive subgroups among the populations in Korea.

• International Journal of Industrial Entomology and Biomaterials
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• 제9권2호
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• pp.255-259
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• 2004

Post-infectional biochemical changes due to Xanthomonas campestris pv. mori (Xcm) infection in five elite mulberry varieties viz., $S_1$, $S_{1635}$, $V_1$, RF $S_{175}$ and JRH was studied under inoculated condition. It was revealed that total soluble sugar and protein content was significantly declined in all the varieties due to X. campestris infection. Total phenol content was at par prior to inoculation in all varieties, but it was significantly increased in $S_1$, RF $S_{175}$, $S_{1635}$ and JRH 7 days after inoculation. The correlation coefficient (r) between total soluble sugar and total phenol content was found positive (r = 0.825) and statistically significant. Similarly, correlation coefficient (r) between total soluble protein and phenol content was found positive (r = 0.897) and statistically significant. The present study indicates that X. campestris infected leaves are nutritionally inferior in quality and the duration of phenol production in a mulberry variety play decisive role on disease resistance.nce.

• The Plant Pathology Journal
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• 제36권5호
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• pp.418-427
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• 2020

Xanthomonas campestris pv. campestris (Xcc), the pathogen of black rot which is the most destructive disease of Brassica vegetables throughout the world. Here, we reported two novel sequence-characterized amplified region (SCAR) markers (i.e., XccR6-60 and XccR6-67) for the detection of Xcc race 6 via re-alignment of the complete genome sequences of Xcc races/strains/pathovars. The specificity of SCAR primer sets was verified by mean of PCR amplification using the genomic DNA template of Xcc races/strains/pathovars and two other plant infecting bacterial strains. The PCR result revealed that the XccR6-60 and XccR6-67 primer sets amplified 692-bp and 917-bp DNA fragments, respectively, specifically from race 6, while no visible amplification was detected in other samples. In addition, the SCAR primers were highly sensitive and can detect from a very low concentration of genomic DNA of Xcc race 6. However, the complete genome sequence of Xcc race 6 is not yet publicly available. Therefore, the cloning and sequencing of XccR6-60 and XccR6-67 fragments from race 6 provide more evidence of the specificity of these markers. These results indicated that the newly developed SCAR markers can successfully, effectively and rapidly detect Xcc race 6 from other Xcc races/strains/pathovars as well as other plant pathogenic bacteria. This is the first report for race-specific molecular markers for Xcc race 6.

• 한국환경농학회지
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• 제33권3호
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• pp.194-197
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• 2014

BACKGROUND: Herbal extracts have been screened for their inhibitory effect of seed germination and root development on weeds, but there is a scarcity of reports for crop growth regulation. The objective of this research was to develop a growth inhibitor on Brassica campestris, and its effective extraction method from herbal medicine extract. METHODS AND RESULTS: Eighty four herbal medicine extracts were tested for their plant growth inhibition activity on B. campestris. The alcohol extracts of Artemisia annua, Cinnamomum cassia, and Mentha arvensis inhibited over 30% of germination and the extract of A. annua, and C. cassia inhibited over 70% of radicle growth at 0.1 % w/w treatment. The partially purified extracts of A. annua, and C. cassia with dichloromethane and hexane showed stronger radicle growth inhibition than the crude extracts on B. campestris. The diethyl ether extract of A. annua showed a similar 50% radicle growth inhibition ($RI_{50}$ = 45 mg/L) to its partially purified extract with dichloromethane or hexane, but the diethyl ether extract of C. cassia showed a worse $RI_{50}$ than the purified extract. CONCLUSION: The alcohol extracts of A. annua, and C. cassia showed potent radicle growth inhibition properties on B. campestris. Diethyl ether proved to be a good solvent for simple extraction from A. annua.

• 한국식물병리학회지
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• 제11권1호
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• pp.53-60
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• 1995

Inoculation with the compatible strain Ds 1 of Xanthomonas campestris pv. vesicatoria caused brownish ad water-soaked lesions, but incompatible strain Bv5-4a produced hypersensitive symptoms with local necrosis on tomato (cv. Kwangyang) leaves. Bacterial populations of the compatible strains Ds 1 propagated more greatly than the incompatible strain Bv5-4a at the frist onset, but no differences were observed 5 days after inoculation. The bacterial infection induced the synthesis and accumulation of soluble proteins in tomato leaves, especially in the incompatible interaction. Native-polyacrylamide gel electrophoresis distinguished the soluble proteins in the tomato leaves infected by the compatible or incompatible strains. A protein of low molecular weight occurred only in the incompatible interaction. Some pathogenesis-related (PR) proteins, especially the 15, 18, 23, 26 and 54 kDa proteins, were detected only in the infected tomato leaves. In the two-dimensional electrophoresis, some proteins with different molecular weights (Mr. 21∼29 kDa) and the pI 8∼9 appeared more distinctly only in the incompatible interaction. These data suggest that the de novo synthesis of some PR proteins in tomato may be significant in defense against X. c. pv. vesicatoria.

• 식물병연구
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• 제11권2호
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• pp.146-151
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• 2005

2000년 수원, 홍천, 연천 지역의 참깨 포장에서 새로운 병해가 발견되었다. 처음에는 잎에 수침상의 작은 점무늬를 형성하다가 점점 커져 괴사가 일어나고 주위로 황화되었다. 심하게 감염된 경우는 병든 잎은 떨어졌다. YDC 배지에서 병원세균을 순수 분리 하였을 때 Xanthomonas 속 세균의 전형적인 특징인 노란색 색소를 띤 세균이 형성되었다. 분리된 세균을 $10^{8}cfu/ml$로 현탁한 후 3주 동안 자란 참깨 잎에 분무 접종하였을 때 처음과 같은 증상이 재현되었다. 분리된 세균은 대조균주 X. campestris pv. sesami LMG865와 지방산 조성 및 다양한 탄소원 이용정도를 이용하여 비교하였을 때 $100\%$의 가능성으로 X. campestris pv. sesami로 동정되었다. 분리된 병원균은 $18\~36^{\circ}C$에서 생장이 양호하였으며, $27^{\circ}C$에서 가장 우수하였다. 이 보고는 국내에서 참깨의 세균성잎마름병 최초 보고이며, P. syringae pv. sesami에 의한 세균성점무늬병과 외부적인 병징으로 구별하기가 매우 어렵다.

• 한국미생물·생명공학회지
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• 제24권4호
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• pp.415-422
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• 1996

A gene coding for a pyruvyl transferase enzyme involved in exopolysaccharide biosynthesis of Zoogloea ramigera 115SLR was isolated and sequenced. A 4.5 kb of BamHI DNA fragment was isolated from chromosomal DNA using a probe derived from ketal pyruvyl transferase gene of Xanthomonas campestris. The nucleotide sequence of 2.66 kb Pst1/HindIII DNA fragment which was homology with a probe revealed the existence of two complete open reading frames (ORF2 and ORF3) and two partial open reading frames (ORFI and ORF4). The deduced amino acid sequence of ORF3 was homologous to the ketalase (GumL product) of X campestris with 49.5% of similarity and 21.6% of identity. ORF2 on the other hand showed the higher identity with the ketalase (ExoV product) of Rhizobium meliloti (36%) as well as the ketalase of X campestris (23%) than that of ORF3. A gene product of ORF2 was determined with a bacteriophage T7 RNA polymerase/promoter system in E. coli. The molecular weight of protein was 33,500 dalton.