• 한국작물학회지
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• 제35권2호
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• pp.132-136
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• 1990

수도 흰잎마름병(Xanthomonas campestris pv. oryzae) 병원세균(K1)의 조직내에서의 증식과 이동 그리고 수공을 통해 추출되는 병원세균의 농도를 조사한 결과를 요약하면 다음과 같다. 1. 저항성 품종에서는 접종 3일후에 약 $10^3$cfu/$\textrm{cm}^2$로 12일까지 큰 변화가 없었으나 리병성 품종에서는 접종 6일에 약 $10^4$cfu/$\textrm{cm}^2$에서 접종 12일에는 약 $10^{8}$-$10^{9}$cfu/$\textrm{cm}^2$로 계속 증식하였다. 2. 병원세균의 접종부위로부터 상, 하향 이동속도 및 증식속도는 상향이동이 약간 빠른 경향이었으며 리병성 품종에서 빠른 증식과 이동속도를 보여 저항성과 밀접한 관계가 있었다. 3. 병원세균의 증식 및 이동은 생육시기에 따른 차이는 없었다. 4. 감염된 잎의 수공을 통해 나오는 병원세균의 농도는 조직내에서 병원세균의 증식 및 이동과 일치하였으며 저항성과도 밀접한 관계가 있었다.

• Toxicological Research
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• 제12권1호
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• pp.17-20
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• 1996

The effect of Fumonisin B1, a mycotoxin produced by Fusarium moniliforme on bacterial viruses P1 and Lambda, was investigated by the virus plaque assay. Fumonisin B1 inhibited the P1 viral multiplication in the concentration range from $100{\mu}g$/ml to $400{\mu}g$/ml. The inhibition was Fumonisin B1 concentration-dependent. Another bacterial virus Lambda multiplication was also inhibited by lower concentration of Fumonisin B1 ($10{\mu}g$/ml~$50{\mu}g$/ml). This inhibition was dependent on Fumonisin B1 and on virus-Fumonisin B1 reaction time. Sensitivity of bacteriophage Lambda to Fumonisin B1 was higher than that of P1 virus. Lambda vital DNA was treated in vitro with Fumonisin B1 at various concentration. Significant DNA fragmentation by Fumonisin 191 was observed in the agarose gel electrophoresis. Lambda viral DNA was partially digested even in the Fumonisin B1 $10{\mu}g$ and the level of its fragmentation was dependent on Fumonisin B1 amount up to $30{\mu}g$ per assay.

• 한국식물병리학회지
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• 제10권1호
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• pp.18-24
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• 1994

Multiplications and pathogenic reactions of different pepper and tomato strains of Xanthomonas campestris pv. vesicatoria were evaluated in the most upper leaves of pepper and tomato plants at different growth stages. Hypersensitive reactions were induced in mature pepper plants by inoculation with only the tomato strains but not with the pepper strains, suggesting the expression of age-related resistance in pepper plants. The age-related resistance also seems to be correlated with an apparent inability of the bacteria to multiply as extensively in mature as in young plants. No significant differences among the Korean and U. S. pepper cultivars tested were found in bacterial multiplication, irrespective of bacterial stain or plant growth stage. Korean tomato cultivars tested also were highly susceptible to either tomato or pepper strains during the development of tomato plants.

• 한국식물병리학회지
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• 제2권2호
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• pp.114-120
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• 1986

BY4품종의 담배를 포장에 이식하면서 이식 하루전과 40일 후에 비병원성 Pseudomonas solanacearum의 현탁액을 담배근권토양에 관주한 결과 7월 상순까지 세균성마름병 발생 속도가 지연되었으나 그 후에는 방제효과가 급속히 감소되었다. 그 결과 잎담배의 $35\%$ 증수 및 kg당 대금으로 $10\%$의 품질상승 효과를 얻을 수 있었다. 비병원성균주처리에 의한 근권상양내 병원균의 밀도증가억제는 인정되지 않았다. $^{32}P$로 표식된 비병원성균주의 담배뿌리를 통한 침입 및 식물체내 이동이 확인되었으며 비병원성균주에 전접종된 담배에 대하여 병원성균주의 침입 및 식물체내 증식이 억제되었다. 이러한 병원성균주의 식물체내 침입 및 증식억제 현상이 병진전 억제와 관련이 있는 것으로 생각되었다.

• 한국작물학회지
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• 제55권4호
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• pp.306-311
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• 2010

저항성원이 다른 7개이 근동질 저항성 계통과 감수성 품종인 Toyonishiki에서 X. oryzae pv. oryzae의 증식과 이동에 관한 시험을 실시하였다. 접종 10일 후, NIL의 접종부위 잎의 세균밀도는 약 $10^5{\sim}10^6\;cfu/cm^2$이었으나 감수성 품종인 Toyonishiki에서는 약 $10^7\;cfu/cm^2$로 높게 나타났다. 이와 같이 감수성 품종에서의 세균 수는 급속히 증가하였으나 NIL에서는 점차적으로 증식하였다. IRBB 103과 Toyonishiki는 접종 25일 후에 접종부위로부터 20cm 위쪽에서 세균이 검출되었으나 다른 NIL에서는 검출되지 않았다. 이와같이 Xa1, Xa4, xa5, Xa7 저항성 유전자는 세균의 이동을 크게 억제하였다.

• The Plant Pathology Journal
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• 제39권5호
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• pp.417-429
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• 2023

Ralstonia solanacearum species complex (RSSC) is a soil borne plant pathogen causing bacterial wilt on various important crops, including Solanaceae plants. The bacterial pathogens within the RSSC produce exopolysaccharide (EPS), a highly complicated nitrogencontaining heteropolymeric polysaccharide, as a major virulence factor. However, the biosynthetic pathway of the EPS in the RSSC has not been fully characterized. To identify genes in EPS production beyond the EPS biosynthetic gene operon, we selected the EPS-defective mutants of R. pseudosolanacearum strain SL341 from Tn5-inserted mutant pool. Among several EPSdefective mutants, we identified a mutant, SL341P4, with a Tn5-insertion in a gene encoding a putative NDP-sugar epimerase, a putative membrane protein with sugar-modifying moiety, in a reverse orientation to EPS biosynthesis gene cluster. This protein showed similar to other NDP-sugar epimerases involved in EPS biosynthesis in many phytopathogens. Mutation of the NDP-sugar epimerase gene reduced EPS production and biofilm formation in R. pseudosolanacearum. Additionally, the SL341P4 mutant exhibited reduced disease severity and incidence of bacterial wilt in tomato plants compared to the wild-type SL341 without alteration of bacterial multiplication. These results indicate that the NDP-sugar epimerase gene is required for EPS production and bacterial virulence in R. pseudosolanacearum.

• 한국식물병리학회지
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• 제10권4호
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• pp.305-313
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• 1994

Typically susceptible lesions were developed on pepper (cv. Hanbyul) leaves inoculated with the compatible strains Ds 1 of Xanthomonas campestris pv. vesicatoria. The lesions appeared first water-soaked and then turned yellow with a chlorotic area. In contrast, the leaves inoculated with the incompatible strain 81-23 initially turned yellow and then developed local necrosis. Multiplication of x. c. pv. vesicatoria in pepper leaves also were distinctly different between the two strains. The strain Ds 1 multiplied more greatly than did the strain 81-23 in the infected leaves. X. c. pv. vesicatoria infection of pepper leaves induced the synthesis of soluble proteins, especially more greatly in the compatible than in the incompatible interactions. Some pathogenesis-related (PR) proteins were detected in the intercellular washing fluid (IWF) and extracts of the infected pepper leaves. In particular, the 32 kDa protein on SDS-PAGE gels appeared intensely in the incompatible interaction. In contrast, some proteins with moluecular masses of 65, 71, and 75 kDa disappeared in the infected pepper leaves. Isoelectric focusing could identify the pIs of soluble proteins in infected pepper leaves. The accumulation of the IWF from infected leaves was more conspicuous in the incompatible than the compatible interaction. These results suggest that some extremely acidic and basic proteins were induced and accumulated in the intercellular spaces of infected pepper leaves.

• 한국작물학회:학술대회논문집
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• 한국작물학회 1990년도 춘계 학술대회지
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• pp.48-49
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• 1990

• Toxicological Research
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• 제5권1호
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• pp.53-59
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• 1989

A mycotoxin Patulin, isolated from apple juice medium cultured with Penicillium patulum NRRL5259, was purified through acid aluminum column using ethyl ether as eluent. The yield of purified patulin crystal was 3mg/ml culture medium after 8 days of shaking culture at 28C. The growth rate of Escherichia coli K12JM103 infected with bacteriophage M13 was decreased by patulin at the concentration range of 1Mug/ml to 10Mu/nl. ED50 of patulin for the bacterial growth was 4.5Mug/ml and 10Mug/ml of patulin caused maximum inhibitory effect (60% inhibition) on the growth.

• The Plant Pathology Journal
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• 제18권6호
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• pp.333-337
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• 2002

Bacteriophage of Xanthomonas axonopodis pv. citri, a causal agent of citrus canker disease, was studied for its cultural characteristics. The relative efficiency of plat-ing (EOP) of 11 phages used to 13 strains off, axonopodis pv. citri tested ranged from 0.8 to 1, indicating that the phages are homogeneous. Homogeneity of the phages suggests that citrusphage belongs to a single group CPK as reported in a previous study. Typical one-step growth of a phage P5 selected from the citrusphages was observed. The EOP of the P5 was dependent upon the media, pH, and temperature. It was observed that multiplication of the phage cultured in Wakimotos potato semisynthetic media at $25^{\circ}C$ was more effective than that in other temperatures, regardless of the bacterial strains and media used. It was observed that pH 6.5 is optimal for multiplication of the phage. In comparison of the EOP among citrusphages $CP_1$, $CP_2$, and P5, multiplicative characteristic of phage P5 in the bacteria on time-course was similar with that of phage $CP_1$. Thus, it was concluded that citrusphage group CPK from Korea is $CP_1$ based on host specificity of the phage as described in a previous study, homogeneity, and its multiplication pattern.