Ralstonia solanacearum, the causative agent of bacterial wilt, is a soil-borne pathogen that poses a widespread threat to plants in the Solanaceae family. To elucidate the mechanism by which limonene exerts its effect...Ralstonia solanacearum, the causative agent of bacterial wilt, is a soil-borne pathogen that poses a widespread threat to plants in the Solanaceae family. To elucidate the mechanism by which limonene exerts its effects on R. solanacearum, we first assessed the impact of limonene on the physiological indicators of the pathogen and subsequently analyzed its transcriptome and metabolome. Our findings indicate that limonene has a potent inhibitory effect on R. solanacearum, and it also suppresses the formation of the bacterial community biofilm. Limonene primarily regulates the terpene biosynthesis pathway in R. solanacearum, thereby potentially affecting signal transduction in the pathogen and disrupting its normal growth and development. These results significantly enhance our understanding of limonene’s response to the induction of bacterial wilt and provide a reference for further prevention and control of R. solanacearum.展开更多
Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strateg...Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future.展开更多
BACKGROUND Ralstonia is a Gram-negative non-fermentative bacterium widespread in nature,and includes four species,Ralstonia pickettii,Ralstonia solanacearum,Ralstonia mannitolilytica,and Ralstonia insidiosa,which were...BACKGROUND Ralstonia is a Gram-negative non-fermentative bacterium widespread in nature,and includes four species,Ralstonia pickettii,Ralstonia solanacearum,Ralstonia mannitolilytica,and Ralstonia insidiosa,which were proposed in 2003.Ralstonia is mainly found in the external water environment,including municipal and medical water purification systems.This bacterium has low toxicity and is a conditional pathogen.It has been reported in recent years that infections due to Ralstonia are increasing.Previous studies have shown that most cases of infection are caused by Ralstonia pickettii,a few by Ralstonia mannitolilytica,and infections caused by Ralstonia insidiosa are rare.CASE SUMMARY A 2-year-old Chinese child suffered from intermittent fever and cough for 20 d and was admitted to hospital with bronchial pneumonia.Bronchoscopy and alveolar lavage fluid culture confirmed Ralstonia insidiosa pneumonia.The infection was well controlled after treatment with meropenem and azithromycin.CONCLUSION Ralstonia infections are increasing,and we report a rare case of Ralstonia insidiosa infection in a child.Clinicians should be vigilant about Ralstonia infections.展开更多
为探究桉树内生沙福芽孢杆菌NP91及生防细菌组合对桉树青枯病的生物防治效果,采用抑菌圈法测定桉树内生沙福芽孢杆菌NP91对青枯病菌的拮抗作用,并用共培养法检测其在桉树体内的定殖转运情况,同时通过蘸根法测定其对桉树青枯病的防治效果...为探究桉树内生沙福芽孢杆菌NP91及生防细菌组合对桉树青枯病的生物防治效果,采用抑菌圈法测定桉树内生沙福芽孢杆菌NP91对青枯病菌的拮抗作用,并用共培养法检测其在桉树体内的定殖转运情况,同时通过蘸根法测定其对桉树青枯病的防治效果,最后通过菌株间的拮抗作用形成3个微生物组合:L-B-4+WCS358r+NP91(组合LWN)、L-B-11+CN181+NP91+WCS358r(组合LCNW)、CN181+WCS417r+NP91+WCS358r(组合CWNW),探究微生物组合对桉树青枯病的防治效果。结果表明,内生沙福芽孢杆菌对青枯病菌具有较强的拮抗活性,且能够在桉苗根部和茎部定殖,接种第15天时,定殖量在根部为6.35 lg CFU/g,在茎部定殖量达到5.23 lg CFU/g。在生防试验中,沙福芽孢杆菌NP91对青枯病的防治效果在第5天和第7天时分别为80.0%和43.8%,但随着时间延长,防治效果逐渐降低。通过多株生防细菌组合后,防治效果最好的组合LCNW对青枯病的防治效果在第7天时达到了100.0%,表明内生沙福芽孢杆菌通过与其他细菌组合可以显著提高对桉树青枯病的防治效果。展开更多
文摘Ralstonia solanacearum, the causative agent of bacterial wilt, is a soil-borne pathogen that poses a widespread threat to plants in the Solanaceae family. To elucidate the mechanism by which limonene exerts its effects on R. solanacearum, we first assessed the impact of limonene on the physiological indicators of the pathogen and subsequently analyzed its transcriptome and metabolome. Our findings indicate that limonene has a potent inhibitory effect on R. solanacearum, and it also suppresses the formation of the bacterial community biofilm. Limonene primarily regulates the terpene biosynthesis pathway in R. solanacearum, thereby potentially affecting signal transduction in the pathogen and disrupting its normal growth and development. These results significantly enhance our understanding of limonene’s response to the induction of bacterial wilt and provide a reference for further prevention and control of R. solanacearum.
基金This work was supported by the National Natural Science Foundation of China(32072399 and 32272641)the Fundamental Research Funds for the Central Universities(GK202201017 and GK202207024)the Program of Fujian Key Laboratory for Monitoring and Integrated Management of Crop Pests,China(MIMCP-202203).
文摘Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future.
文摘BACKGROUND Ralstonia is a Gram-negative non-fermentative bacterium widespread in nature,and includes four species,Ralstonia pickettii,Ralstonia solanacearum,Ralstonia mannitolilytica,and Ralstonia insidiosa,which were proposed in 2003.Ralstonia is mainly found in the external water environment,including municipal and medical water purification systems.This bacterium has low toxicity and is a conditional pathogen.It has been reported in recent years that infections due to Ralstonia are increasing.Previous studies have shown that most cases of infection are caused by Ralstonia pickettii,a few by Ralstonia mannitolilytica,and infections caused by Ralstonia insidiosa are rare.CASE SUMMARY A 2-year-old Chinese child suffered from intermittent fever and cough for 20 d and was admitted to hospital with bronchial pneumonia.Bronchoscopy and alveolar lavage fluid culture confirmed Ralstonia insidiosa pneumonia.The infection was well controlled after treatment with meropenem and azithromycin.CONCLUSION Ralstonia infections are increasing,and we report a rare case of Ralstonia insidiosa infection in a child.Clinicians should be vigilant about Ralstonia infections.
文摘为探究桉树内生沙福芽孢杆菌NP91及生防细菌组合对桉树青枯病的生物防治效果,采用抑菌圈法测定桉树内生沙福芽孢杆菌NP91对青枯病菌的拮抗作用,并用共培养法检测其在桉树体内的定殖转运情况,同时通过蘸根法测定其对桉树青枯病的防治效果,最后通过菌株间的拮抗作用形成3个微生物组合:L-B-4+WCS358r+NP91(组合LWN)、L-B-11+CN181+NP91+WCS358r(组合LCNW)、CN181+WCS417r+NP91+WCS358r(组合CWNW),探究微生物组合对桉树青枯病的防治效果。结果表明,内生沙福芽孢杆菌对青枯病菌具有较强的拮抗活性,且能够在桉苗根部和茎部定殖,接种第15天时,定殖量在根部为6.35 lg CFU/g,在茎部定殖量达到5.23 lg CFU/g。在生防试验中,沙福芽孢杆菌NP91对青枯病的防治效果在第5天和第7天时分别为80.0%和43.8%,但随着时间延长,防治效果逐渐降低。通过多株生防细菌组合后,防治效果最好的组合LCNW对青枯病的防治效果在第7天时达到了100.0%,表明内生沙福芽孢杆菌通过与其他细菌组合可以显著提高对桉树青枯病的防治效果。
