The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter...The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter michiganensis subsp.michiganensis(Cmm),Pseudomonas syringae pv.tomato(Pst),Ralstonia solanacearum(Rs),and Xanthomonas axonopodis(Xa).Synthetic chemical products are used mostly on disease plant control,but overuse generates resistance to bacterial control.This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam.leaves against At,Cmm,Pst,Rs,and Xa,as well as information about this plant species’chemical composition.Antibacterial activity against pathogens observed by microplate technique,phytochemical screening,and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity.The growth inhibition rate ranged between 0.08%and 99.94%.The inhibitory concentration,IC50,required to inhibit 50%of At,Cmm,Pst,Rs,and Xa bacterial growth,was 276.67,350.48,277.85,351.49,and 283.22 mg/L,respectively.Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased.Moringa oleifera extract can be recommended as a potent bio-bactericide.展开更多
Plant growth promotion indole-3-acetic acid (IAA) is the most abundant natural auxin that plays diverse roles in plant growth, development and plant immunity. Perturbing auxin homeostasis appears to be a common virule...Plant growth promotion indole-3-acetic acid (IAA) is the most abundant natural auxin that plays diverse roles in plant growth, development and plant immunity. Perturbing auxin homeostasis appears to be a common virulence mechanism, as many pathogens can synthesize auxin-like molecules. In other hand, the addition of plant growth promotion rhizobacteria (PGPR) that are able to produce auxins promotes plant growth and provides protection against pathogens. Techniques as high performance liquid chromatography (HPLC) and gas chromatography (GC) are used to quantify auxins produced by microorganism and plants at high precision and sensitivity, even though those techniques are expensive and require a big number of solvents. For these reasons, the aim of the present study was to develop a fast microplate technique for auxin detection, in Bacillus subtilis strains using salkowski reagent. For auxin quantification, calibration curves were done with alcohol, landy medium and water and the R2 were calculated. The microplate techniques were able to quantify auxin production by B. subtillis stains.展开更多
基金This work was supported by PRODEP throughthe support of the postdoctoral fellowship granted to the first author(Trade No.511-6/18-391)The authors thank the academic body of Ecología Aplicada(UAT-CA-156)for the support obtained from their researchers to conductthis investigation.
文摘The tomato(Solanum lycopersicum L.)is one of the world’s most important vegetable crops.Still,phytopathogenic bacteria affect the yield and quality of tomato cultivation,like Agrobacterium tumefeciens(At),Clavibacter michiganensis subsp.michiganensis(Cmm),Pseudomonas syringae pv.tomato(Pst),Ralstonia solanacearum(Rs),and Xanthomonas axonopodis(Xa).Synthetic chemical products are used mostly on disease plant control,but overuse generates resistance to bacterial control.This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam.leaves against At,Cmm,Pst,Rs,and Xa,as well as information about this plant species’chemical composition.Antibacterial activity against pathogens observed by microplate technique,phytochemical screening,and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity.The growth inhibition rate ranged between 0.08%and 99.94%.The inhibitory concentration,IC50,required to inhibit 50%of At,Cmm,Pst,Rs,and Xa bacterial growth,was 276.67,350.48,277.85,351.49,and 283.22 mg/L,respectively.Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased.Moringa oleifera extract can be recommended as a potent bio-bactericide.
文摘Plant growth promotion indole-3-acetic acid (IAA) is the most abundant natural auxin that plays diverse roles in plant growth, development and plant immunity. Perturbing auxin homeostasis appears to be a common virulence mechanism, as many pathogens can synthesize auxin-like molecules. In other hand, the addition of plant growth promotion rhizobacteria (PGPR) that are able to produce auxins promotes plant growth and provides protection against pathogens. Techniques as high performance liquid chromatography (HPLC) and gas chromatography (GC) are used to quantify auxins produced by microorganism and plants at high precision and sensitivity, even though those techniques are expensive and require a big number of solvents. For these reasons, the aim of the present study was to develop a fast microplate technique for auxin detection, in Bacillus subtilis strains using salkowski reagent. For auxin quantification, calibration curves were done with alcohol, landy medium and water and the R2 were calculated. The microplate techniques were able to quantify auxin production by B. subtillis stains.
