Bacterial diseases severely impact global agriculture,leading to substantial economic and yield losses.Citrus Huanglongbing(HLB),caused by Candidatus Liberibacter asiaticus(CLas),is a devastating disease,affecting cit...Bacterial diseases severely impact global agriculture,leading to substantial economic and yield losses.Citrus Huanglongbing(HLB),caused by Candidatus Liberibacter asiaticus(CLas),is a devastating disease,affecting citrus production worldwide(Graham et al.,2024).Likewise,bac-terial canker disease caused by Pseudomonas syringae pv.actinidiae(Psa)in kiwifruit(Actinidia spp.)resulted in yield reductions exceeding 80%,threatening industry collapse(Vanneste,2017).Current control strategies primarily rely on emergent chemical pesticides or the desperate yet common strategy of tree elimination and diseased-branch excision.展开更多
Infection and intoxication are two common types of foodborne illnesses throughout the world.The aim of the present work was to isolate and characterize biosurfactant producing bacteria fromgroundnut oil cake dumping s...Infection and intoxication are two common types of foodborne illnesses throughout the world.The aim of the present work was to isolate and characterize biosurfactant producing bacteria fromgroundnut oil cake dumping sites and evaluate their biocontrol effects against foodborne pathogens.Bacteria were isolated by enrichment culture technique and preliminary screening method.Biosurfactant activity evaluation was carried out by oil displacement,drop collapse test,lipase activity,hemolytic activity,emulsification index and emulsification assay methods.16s rRNA sequence analysis was used for the isolate identification.Crude biosurfactant was extracted by acid precipitation method and characterized using FTIR(Fourier Transform Infrared Spectroscopy).Antibacterial activity was investigated using disc diffusion method.CMCand surface reduction were analyzed by DuNouy tensiometer.Top 10 strains were selected for biosurfactant activity assessment from the total 30 isolates.In addition,16s rRNA sequence identified that the potential isolate was Bacillus pseudomycoides OR 1.Then,FTIR result of the extracted biosurfactant established the extract as a lipopeptide based on the absorption peaks at 3500 to 3200 cm^-1 and 2963 to 2854.68 cm^-1,respectively.50μg/mL of lipopeptide showed the highest antibacterial activity.Critical Micelle Concentration(CMC)of the lipopeptide was 60 mg/L and it reduced the surface tension of water from 71.6 to 31.6 mN/m.Hence,this study widens the scope to employ the bacterial lipopeptide surfactant as a promising biocontrol agent against foodborne pathogens.展开更多
Rice sheath blight is widely distributed throughout the world, it can cause damage on many kinds of crops. Pathogen characteristics, infection cycle, occurrence law, damage law and different control methods of rice sh...Rice sheath blight is widely distributed throughout the world, it can cause damage on many kinds of crops. Pathogen characteristics, infection cycle, occurrence law, damage law and different control methods of rice sheath blight in China are summarized, which will provide foundation for further worldwide research on the disease.展开更多
Pathogen and characteristics,occurrence law,damage symptom of Paulownia fortunei witches broom disease were simply described,and the control method of the disease was summarized.
基金supported by the National Key R&D Program of China(2022YFD1400200)to L.H.
文摘Bacterial diseases severely impact global agriculture,leading to substantial economic and yield losses.Citrus Huanglongbing(HLB),caused by Candidatus Liberibacter asiaticus(CLas),is a devastating disease,affecting citrus production worldwide(Graham et al.,2024).Likewise,bac-terial canker disease caused by Pseudomonas syringae pv.actinidiae(Psa)in kiwifruit(Actinidia spp.)resulted in yield reductions exceeding 80%,threatening industry collapse(Vanneste,2017).Current control strategies primarily rely on emergent chemical pesticides or the desperate yet common strategy of tree elimination and diseased-branch excision.
文摘Infection and intoxication are two common types of foodborne illnesses throughout the world.The aim of the present work was to isolate and characterize biosurfactant producing bacteria fromgroundnut oil cake dumping sites and evaluate their biocontrol effects against foodborne pathogens.Bacteria were isolated by enrichment culture technique and preliminary screening method.Biosurfactant activity evaluation was carried out by oil displacement,drop collapse test,lipase activity,hemolytic activity,emulsification index and emulsification assay methods.16s rRNA sequence analysis was used for the isolate identification.Crude biosurfactant was extracted by acid precipitation method and characterized using FTIR(Fourier Transform Infrared Spectroscopy).Antibacterial activity was investigated using disc diffusion method.CMCand surface reduction were analyzed by DuNouy tensiometer.Top 10 strains were selected for biosurfactant activity assessment from the total 30 isolates.In addition,16s rRNA sequence identified that the potential isolate was Bacillus pseudomycoides OR 1.Then,FTIR result of the extracted biosurfactant established the extract as a lipopeptide based on the absorption peaks at 3500 to 3200 cm^-1 and 2963 to 2854.68 cm^-1,respectively.50μg/mL of lipopeptide showed the highest antibacterial activity.Critical Micelle Concentration(CMC)of the lipopeptide was 60 mg/L and it reduced the surface tension of water from 71.6 to 31.6 mN/m.Hence,this study widens the scope to employ the bacterial lipopeptide surfactant as a promising biocontrol agent against foodborne pathogens.
文摘Rice sheath blight is widely distributed throughout the world, it can cause damage on many kinds of crops. Pathogen characteristics, infection cycle, occurrence law, damage law and different control methods of rice sheath blight in China are summarized, which will provide foundation for further worldwide research on the disease.
文摘Pathogen and characteristics,occurrence law,damage symptom of Paulownia fortunei witches broom disease were simply described,and the control method of the disease was summarized.
