• The Plant Pathology Journal
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• v.17 no.1
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• pp.29-35
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• 2001

Early infection process of Phytophthora capsici in pumpkin stems was similar in the compatible and incompatible interactions 24 h after inoculation. Intercellularly growing hyphae penetrated host parenchyma cells by growing hyphae penetrated host parenchyma cells by forming haustoria. An extrahaustorial matrix was found around the haustoria in both compatible and incompatible interactions. No wall appositions were observed at the infection sites in the parenchyma cells. In the compatible interaction, infecting hyphae grew well in the intercellular spaces between xylem vessels in stem tissues. Degraded host cell wall, plasmolysis of plasma membrane, and degenerated chloroplasts were pathological features of pumpkin stem tissues in both compatible and incompatible interactions. A characteristic host response in the resistant pumkin cultivar Danmatmaetdol was rapid cytoplasmic movement of host cells toward the oomycete haustoria.

• Korean Journal Plant Pathology
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• v.10 no.2
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• pp.83-91
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• 1994

Stem tissues of tomato plants (cv. Kwanyang) inoculated with Phytophthora capsici were examined by light and electron microscopy to compare early cytological differences between comaptible and incompatible interactions of tomatoes with the fungus. Twenty four hours after inoculation, the compatible isolate S 197 colonized severely the epidermis, cortex, and xylem vessels of stem tissue, whereas only few fungal cells colonized the stem tissues inoculated with the incompatible isolate CBS 178.26. Fragmented plasma membrane, distorted chloroplast, degraded cell wall, remnants of host cytoplasm were early ultrastructural features of the damaged host cell observed both in the compatible and incompatible interaction, a number of vesicles were distributed in the space between fungal cell walls and plasma membrane. The degradation of host cell walls by P. capsici was more pronounced in the compatible than the incompatible interactions. The incompatible interactions of tomato cells with P. capsici were characterized by formation of host cell wall apposition in the cortical parenchyma cells, indicating that the apposition of electron-dense material from the host cell walls may function as a plant defense reaction to the fungus. The fungal cells encased by wall appositions had abnormal cytoplasm and separated plasma membranes. The haustorium which formed from the fungal hyphae did not further penetrate through the host wall apposition and cytoplasmic aggregation, especially in the incompatible reactions. In contrast, the haustorium of the compatible isolate S 197 was not encased by wall appositions.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.2
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• pp.162-168
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• 2007

Compatible and incompatible interactions of near-isogenic lines containing one of Xa1, Xa3, and Xa7 resistance genes with Japanese bacterial blight isolates (T7174, T7147, and T7133) were examined in order to determine the variation of bacterial blight resistance and the stability of resistance gene. IRBB 101 line having a Xal gene was compatible (host susceptible) with T7147 and T7133 isolates but incompatible (host resistant) with T7174 isolate at all the tested rice growth stages. IRBB 103 line having a Xa3 gene was susceptible or moderately resistant to the three isolates at seedling and maximum tillering stage but resistant at heading stage. IRBB 101 line having a Xa7 gene was semi-compatible with the three isolates at seedling stage but incompatible at the other growth stages. Overall there were clear differences between compatible and incompatible interactions of rice with Xanthomonas oryzae pv. oryzae races. In the mixed inoculations of compatible and incompatible isolates, the lesion length from near-isogenic lines decreased as the ratios of incompatible races increased. When the distinction between compatible and incompatible isolates was unclear, there was almost no variation of lesion length regardless of mixed ratios. The pathogenicity of the mixed races in the incompatible Interactions increased rather than the individual inoculation whereas the lesion length of compatible interactions was similar to that of the individual inoculation. These data indicate the incompatible races inhibit the virulence of a compatible race but compatible races increase the disease occurrence due to incompatible races. Furthermore, IRBB 107 line that showed resistance to all the isolates at all the tested growth stages was considered as a good parent f3r breeding of resistant variety.

• Korean Journal Plant Pathology
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• v.10 no.4
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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.

• Korean Journal Plant Pathology
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• v.11 no.1
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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.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2000.10a
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• pp.11.2-11
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• 2000

• Molecules and Cells
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• v.23 no.2
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• pp.207-214
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• 2007

lant ${\beta}$-1, 3-glucanases are involved in plant defense and in development. Very little data are available on the expression of rice glucanases both in developmental tissues and under various stresses. In this study, we cloned and characterized twenty-seven rice ${\beta}$-1, 3-glucanases (OsGlu) from at total of 71 putative glucanases. The OsGlu genes were obtained by PCR from a cDNA library and were classified into seven groups (Group I to VII) according to their DNA or amino acid sequence homology. Analysis of the expression of the twenty-seven OsGlu genes by Northern blotting revealed that they were differentially expressed in different developmental tissues as well as in response to plant hormones, biotic stress, high salt etc. OsGlu11 and 27 in Group IV were clearly expressed only in stem and leaf and were also induced strongly by SA (5 mM), ABA ($200{\mu}M$), and M. grisea. OsGlu1, 10, 11, and 14 were induced earlier and to higher levels in incompatible M. grisea interaction than in compatible one. Taken together, our findings suggest that the twenty-seven rice OsGlu gene products play diverse roles not only in plant defense but also in hormonal responses and in development.

• The Plant Pathology Journal
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• v.16 no.1
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• pp.9-18
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• 2000

Using differential display techniques, a new acidic pathogenesis-related (PR) protein-1 cDNA (GMPRla) gene was isolated from a cDNA library of soybean (Glycinemax L.Merr, cultivar Jangyup) hypocotyls infected by Phytophthora sojae f. sp. glycines. The 741 bp of fulllength GMPRla clone contains an open reading frame of 525 nucleotides encoding 174 amino acid residues (pI 4.23) with a putative signal peptide of 27 amino acids in the N-terminus. Predicted molecular weight of the protein is 18,767 Da. The deduced amino acid sequence of GMPRla has a high level of identity with PR-1 proteins from Brassica napus, Nicotiana tabacum, and Sambucus nigra. The GMPRla mRNA was more strongly expressed in the incompatible than the compatible interaction. The transcript accumulation was induced in the soybbean hypocotyls by treatment with ethephon or DL-$\beta$-amino-n-butyric acid, but not by wounding. In situ hybridization data showed that GMPRIa mRNAs were usually localized in the vascular bundle of hypocotyl tissues, especially phloem tissue. Differences between compatible and incompatible interactions in the timing of GMPRla mRNA accumulation were remarkable, but the spatial distribution of GMPRla mRNA was similar in both interactions. However, more GMPRla mRNA was accumulated in soybean hypocotyls at 6 and 24 h after inoculation.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.268-279
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• 2021

Citrus scab, caused by the fungal pathogen Elsinoë fawcettii, is one of the most important fungal diseases affecting Citrus spp. Citrus scab affects young tissues, including the leaves, twigs, and fruits, and produces severe fruit blemishes that reduce the market value of fresh fruits. To study the molecular responses of satsuma mandarin (C. unshiu) to E. fawcettii, plant hormone-related gene expression was analyzed in response to host-compatible (SM16-1) and host-incompatible (DAR70024) isolates. In the early phase of infection by E. fawcettii, jasmonic acid- and salicylic acid-related gene expression was induced in response to infection with the compatible isolate. However, as symptoms advanced during the late phase of the infection, the jasmonic acid- and salicylic acid-related gene expression was downregulated. The gene expression patterns were compared between compatible and incompatible interactions. As scabs were accompanied by altered tissue growth surrounding the infection site, we conducted gibberellic acid- and abscisic acid-related gene expression analysis and assessed the content of these acids during scab symptom development. Our results showed that gibberellic and abscisic acid-related gene expression and hormonal changes were reduced and induced in response to the infection, respectively. Accordingly, we propose that jasmonic and salicylic acids play a role in the early response to citrus scab, whereas gibberellic and abscisic acids participate in symptom development.

• BMB Reports
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• v.38 no.4
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• pp.420-431
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• 2005

The differentially virulent race T1 of common bunt (Tilletia tritici) was used to inoculate the wheat lines Neepawa (compatible) and its sib BW553 (incompatible) that are nearly isogenic for the Bt-10 resistance gene. Inoculated crown tissues were used to construct a suppression subtractive hybridization (SSH) cDNA library. Of the 1920 clones arrayed from the SSH cDNA library, approximately 10% were differentially regulated. A total of 168 differentially up-regulated and 25 down-regulated genes were identified and sequenced; 71% sequences had significant homology to genes of known function, of which 59% appeared to have roles in cellular metabolism and development, 24% in abiotic/biotic stress responses, 3% involved in transcription and signal transduction responses. Two putative resistance genes and a transcription factor were identified among the up regulated sequences. The expression of several candidate genes including a lipase, two non-specific lipid transfer proteins (ns-LTPs), and several wheat pathogenesis-related (PR)-proteins, was evaluated following 4 to 32 days post-inoculation in compatible and incompatible interactions. Results confirmed the higher overall expression of these genes in resistant BW553 compared to susceptible Neepawa, and the differential up-regulation of wheat lipase, chitinase and PR-1 proteins in the expression of the incompatible interaction.