Despite large numbers of studies about defense response, processes involved in the resistance of plants to incompatible pathogens are still largely uncharacterized. The objective of this study was to identify genes in...Despite large numbers of studies about defense response, processes involved in the resistance of plants to incompatible pathogens are still largely uncharacterized. The objective of this study was to identify genes involved in defense response by cDNA array analysis and to gain knowledge about the functions of the genes involved in defense response. Approximately 20000 rice cDNA clones were arrayed on nylon filters. RNA samples isolated from different rice lines after infection with incompatible strains or isolates of Xanthomonas oryzae pv. oryzae or Pyricularia grisea, respectively, were used to synthesize cDNA as probes for screening the cDNA arrays. A total of 100 differentially expressed unique sequences were identified from 5 pathogen-host combinations. Fifty-three sequences were detected as showing enhanced expression and 47 sequences were detected as showing repressed expression after pathogen infection. Sequence analysis revealed that most of the 100 sequences had various degrees of homology with genes in databases which encode or putatively encode transcription regulating proteins, translation regulating proteins, transport proteins, kinases, metabolic enzymes, and proteins involved in other functions. Most of the genes have not been previously reported as being involved in the disease resistance response in rice. The results from cDNA arrays, reverse transcription-polymerase chain reaction, and RNA gel blot analysis suggest that activation or repression of most of these genes might occur commonly in the defense response.展开更多
Tomato bacterial wilt caused by Ralstonia solanacearum seriously threats tomato growth in tropical and temperate regions around the world.This study reported an antagonistic bacterial strain, Bacillus amyloliquefacien...Tomato bacterial wilt caused by Ralstonia solanacearum seriously threats tomato growth in tropical and temperate regions around the world.This study reported an antagonistic bacterial strain, Bacillus amyloliquefaciens strain SQRT3, isolated from the rhizosphere soil of tomato plants, which strongly inhibited in vitro growth of pathogenic R.solanacearum.The suppression of tomato bacterial wilt by strain SQRT3 was demonstrated under greenhouse conditions.Additionally, induced systemic resistance(ISR) in tomato as one of the potential disease suppression mechanisms was investigated in the plants inoculated with the isolated bacterial strain SQRT3.The results showed that strain SQRT3 applied with R.solanacearum by drenching significantly reduced tomato bacterial wilt by 68.1% biocontrol efficiency(BE) and suppressed the R.solanacearum populations in the rhizosphere soil compared to the control only drenched with R.solanacearum.The BE of the isolated bacterial strain SQRT3 against tomato wilt increased to 84.1%by root-dipping.Tomato plants treated with both strain SQRT3 and R.solanacearum showed increases in activities of peroxidase and polyphenol oxidase compared with other treatments.The application of strain SQRT3 reduced membrane lipid peroxidation in tomato leaves.The expressions of marker genes for jasmonic acid-and salicylic acid-dependent signaling pathways were faster and stronger in tomato plants treated with both strain SQRT3 and R.solanacearum than in plants treated with either R.solanacearum or strain SQRT3 alone.Collectively, the findings indicated that strain SQRT3 can effectively control tomato wilt.展开更多
基金This research was supported by the National Natural Science Foundation of China (Grant No.39970450), the National Program of High Technology Development of China (863), the National Program of Research and Development of Transgenic Plants of China, an
文摘Despite large numbers of studies about defense response, processes involved in the resistance of plants to incompatible pathogens are still largely uncharacterized. The objective of this study was to identify genes involved in defense response by cDNA array analysis and to gain knowledge about the functions of the genes involved in defense response. Approximately 20000 rice cDNA clones were arrayed on nylon filters. RNA samples isolated from different rice lines after infection with incompatible strains or isolates of Xanthomonas oryzae pv. oryzae or Pyricularia grisea, respectively, were used to synthesize cDNA as probes for screening the cDNA arrays. A total of 100 differentially expressed unique sequences were identified from 5 pathogen-host combinations. Fifty-three sequences were detected as showing enhanced expression and 47 sequences were detected as showing repressed expression after pathogen infection. Sequence analysis revealed that most of the 100 sequences had various degrees of homology with genes in databases which encode or putatively encode transcription regulating proteins, translation regulating proteins, transport proteins, kinases, metabolic enzymes, and proteins involved in other functions. Most of the genes have not been previously reported as being involved in the disease resistance response in rice. The results from cDNA arrays, reverse transcription-polymerase chain reaction, and RNA gel blot analysis suggest that activation or repression of most of these genes might occur commonly in the defense response.
基金financially supported by the Science and Technology Program of Jiangsu Province,China(No.BE2014398)the National Natural Science Foundation of China(No.41571242)
文摘Tomato bacterial wilt caused by Ralstonia solanacearum seriously threats tomato growth in tropical and temperate regions around the world.This study reported an antagonistic bacterial strain, Bacillus amyloliquefaciens strain SQRT3, isolated from the rhizosphere soil of tomato plants, which strongly inhibited in vitro growth of pathogenic R.solanacearum.The suppression of tomato bacterial wilt by strain SQRT3 was demonstrated under greenhouse conditions.Additionally, induced systemic resistance(ISR) in tomato as one of the potential disease suppression mechanisms was investigated in the plants inoculated with the isolated bacterial strain SQRT3.The results showed that strain SQRT3 applied with R.solanacearum by drenching significantly reduced tomato bacterial wilt by 68.1% biocontrol efficiency(BE) and suppressed the R.solanacearum populations in the rhizosphere soil compared to the control only drenched with R.solanacearum.The BE of the isolated bacterial strain SQRT3 against tomato wilt increased to 84.1%by root-dipping.Tomato plants treated with both strain SQRT3 and R.solanacearum showed increases in activities of peroxidase and polyphenol oxidase compared with other treatments.The application of strain SQRT3 reduced membrane lipid peroxidation in tomato leaves.The expressions of marker genes for jasmonic acid-and salicylic acid-dependent signaling pathways were faster and stronger in tomato plants treated with both strain SQRT3 and R.solanacearum than in plants treated with either R.solanacearum or strain SQRT3 alone.Collectively, the findings indicated that strain SQRT3 can effectively control tomato wilt.
