Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although ...Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although these pests have not established in China,precautions must be taken due to their highly destructive nature.Thus,we predicted the potential geographic distribution of B.bryoniae and B.neohumeralis across the world and in particular China by ecological niche modeling of the Maximum Entropy(Max Ent)model with the occurrence records of these two species.Bactrocera bryoniae and B.neohumeralis exhibit similar potential geographic distribution ranges across the world and in China,and each species was predicted to be able to distribute to over 20%of the globe.Globally,the potential geographic distribution ranges for these two fruit fly species included southern Asia,the central and the southeast coast of Africa,southern North America,northern and central South America,and Australia.While within China,most of the southern Yangtze River area was found suitable for these species.Notably,southern China was considered to have the highest risk of B.bryoniae and B.neohumeralis invasions.Our study identifies the regions at high risk for potential establishment of B.bryoniae and B.neohumeralis in the world and in particular China,and informs the development of inspection and biosecurity/quarantine measures to prevent and control their invasions.展开更多
Fluopyram is an succinate dehydrogenase inhibitors(SDHI)fungicide that has been registered in China to control gummy stem blight(GSB)in watermelons for many years.However,whether the field pathogens of GSB are still s...Fluopyram is an succinate dehydrogenase inhibitors(SDHI)fungicide that has been registered in China to control gummy stem blight(GSB)in watermelons for many years.However,whether the field pathogens of GSB are still sensitive to fluopyram or not is unknown.Therefore,we collected 69 Didymella bryoniae isolates from the fields that usually use fluopyram to control GSB to determine the sensitivity change.The EC_(50)(50%inhibition effect)values of fluopyram against D.bryoniae ranged from 0.0691 to 0.3503μg mL^(–1) and the variation factor was 5.07.The mean EC_(50) value was(0.1579±0.0669)μg mL^(–1) and the curve of sensitivity was unimodal.No resistant strains were found in the isolates,which means that the pathogens were still sensitive to fluopyram.The minimal inhibition concentration(MIC)of fluopyram against D.bryoniae was 3μg mL^(–1).Four low-resistant mutants and two medium-resistant mutants were obtained using fungicide taming and the resistance of mutants could be inherited stably.The growth rate of mutants decreased significantly compared with that of wild-type strains while the biomass of most mutants was similar to that of wild-type strains.The sensitivity of most resistant mutants to various stresses was increased compared with that of wild-type strains.The virulence of mutants receded except for low-resistant mutant XN51FR-1,which had the same lesion area as XN51 on the watermelon leaves.The results indicated that the fitness of resistant mutants was decreased compared with that of wild-type strains.The cross-resistance assay indicated that fluopyram-resistant mutants were positive cross-resistant to all six SDHI fungicides in this test but were still sensitive to fluazinam and tebuconazole.So the resistance risk of D.bryoniae to fluopyram was moderate.In addition,we found that the SdhB gene of low-resistant mutant XN30FR-1 had three new point mutations at positions K258N,A259P,and H277N.Medium-resistant mutant XN52FR-1 showed a mutation at position H277N and other mutants did not have any point mutation.展开更多
Objective To evaluate the in vitro anti-diabetic effects of Bryonia dioica roots extracts,in-cluding water-acetone extracts and their ethyl acetate and butanol fractions,and chloroform-methanol extracts.Methods The to...Objective To evaluate the in vitro anti-diabetic effects of Bryonia dioica roots extracts,in-cluding water-acetone extracts and their ethyl acetate and butanol fractions,and chloroform-methanol extracts.Methods The total phenolic,flavonoid,flavonol,and saponin contents in the Bryonia dioica root extracts(chloroform-methanol extracts,water-acetone extracts and their ethyl acetate and butanol fractions)were determined using colorimetric methods with Folin-Ciocalteu,aluminum trichloride,and vanillin reagents,respectively.The in vitro anti-diabetic activity was evaluated by measuring the half-maximal inhibitory concentration(IC_(50))values of these root extracts againstα-amylase andα-glucosidase activities,evaluating their effects onα-amy-lase kinetics,quantifying the inhibition of bovine serum albumin(BSA)glycation using fluo-rometry to assess advanced glycation end products(AGE)production,and determining glu-cose uptake by isolated rat hemidiaphragm.Additionally,molecular docking analysis was conducted to investigate the binding affinity and interaction types between Bryonia dioica lig-ands(cucurbitacin B,bryogénin,vitexin,and isovitexin)and target enzymes,and a phyto-chemical-targets interaction network was constructed.Results Forα-amylase inhibition,ethyl acetate fraction demonstrated the most potent activi-ty(IC_(50)=145.95μg/mL),followed by chloroform-methanol extract(IC_(50)=300.86μg/mL).Water-acetone root extracts and their ethyl acetate and butanol fractions inhibited theα-glucosidase activity with IC50 values ranging from 562.88 to 583.90μg/mL.Both ethyl acetate and butanol fractions strongly inhibited non-enzymatic BSA glycation(IC_(50)=318.26 and 323.12μg/mL,respectively).The incubation of isolated rat hemidiaphragms with the ethyl acetate fraction(5 mg/mL)significantly increased glucose uptake(35.16%;P<0.0001),exceeding the effects of insulin(29.27%),chloroform-methanol extract(24.07%),and catechin(15.27%).Molecular docking revealed that cucurbitacin B exhibited the strongest docking scores againstα-amylase(-16.4 kcal/mol),andα-glucosidase(-14.2 kcal/mol).Compared with other ligands,isovitexin formed the maximum number of hydrogen bonds with theα-amylase active site residues(Asp300,Asp197,and Glu233),α-glucosidase residues(Ser13,Arg44,Met86,Gly10,Asp39,and Tyr131)and other residues(Arg195,Trp59,His299,and Tyr62).Network analysis identified 36 overlapping targets between Bryonia dioica phyto-chemicals and type 2 diabetes mellitus-associated genes,with cucurbitacins and polyphenols interacting withα-amylase,α-glucosidase,and Glut4 translocation pathway targets.Conclusion Bryonia dioica root extracts demonstrated promising in vitro anti-diabetic activi-ty through multiple mechanisms,including the inhibitory effect on digestive enzymes,pro-tein antiglycation potential,and enhancement of glucose uptake,suggesting their potential as a source for anti-diabetic drugs development.展开更多
基金supported by the National Key R&D Program of China(2017YFC1200600 and 2016YFC1202104)the Innovation Team of Modern Agricultural Industry Generic Key Technology R&D of Guangdong Province,China(2019KJ134)+1 种基金the Open Fund of the Guangxi Key Laboratory of Biology for Crop Diseases and Insect Pests,China(2016-KF-3)A student scholarship was provided by the Harry Butler Institute,Murdoch University,Australia。
文摘Bactrocera bryoniae and Bactrocera neohumeralis are highly destructive and major biosecurity/quarantine pests of fruit and vegetable in the tropical and subtropical regions in the South Pacific and Australia.Although these pests have not established in China,precautions must be taken due to their highly destructive nature.Thus,we predicted the potential geographic distribution of B.bryoniae and B.neohumeralis across the world and in particular China by ecological niche modeling of the Maximum Entropy(Max Ent)model with the occurrence records of these two species.Bactrocera bryoniae and B.neohumeralis exhibit similar potential geographic distribution ranges across the world and in China,and each species was predicted to be able to distribute to over 20%of the globe.Globally,the potential geographic distribution ranges for these two fruit fly species included southern Asia,the central and the southeast coast of Africa,southern North America,northern and central South America,and Australia.While within China,most of the southern Yangtze River area was found suitable for these species.Notably,southern China was considered to have the highest risk of B.bryoniae and B.neohumeralis invasions.Our study identifies the regions at high risk for potential establishment of B.bryoniae and B.neohumeralis in the world and in particular China,and informs the development of inspection and biosecurity/quarantine measures to prevent and control their invasions.
基金sponsored by the National Key R&D Program of China(2022YFD1400900)the National Natural Science Foundation of China(32272585)the Fundamental Research Funds for the Central Universities,China(KYCXJC2023003)。
文摘Fluopyram is an succinate dehydrogenase inhibitors(SDHI)fungicide that has been registered in China to control gummy stem blight(GSB)in watermelons for many years.However,whether the field pathogens of GSB are still sensitive to fluopyram or not is unknown.Therefore,we collected 69 Didymella bryoniae isolates from the fields that usually use fluopyram to control GSB to determine the sensitivity change.The EC_(50)(50%inhibition effect)values of fluopyram against D.bryoniae ranged from 0.0691 to 0.3503μg mL^(–1) and the variation factor was 5.07.The mean EC_(50) value was(0.1579±0.0669)μg mL^(–1) and the curve of sensitivity was unimodal.No resistant strains were found in the isolates,which means that the pathogens were still sensitive to fluopyram.The minimal inhibition concentration(MIC)of fluopyram against D.bryoniae was 3μg mL^(–1).Four low-resistant mutants and two medium-resistant mutants were obtained using fungicide taming and the resistance of mutants could be inherited stably.The growth rate of mutants decreased significantly compared with that of wild-type strains while the biomass of most mutants was similar to that of wild-type strains.The sensitivity of most resistant mutants to various stresses was increased compared with that of wild-type strains.The virulence of mutants receded except for low-resistant mutant XN51FR-1,which had the same lesion area as XN51 on the watermelon leaves.The results indicated that the fitness of resistant mutants was decreased compared with that of wild-type strains.The cross-resistance assay indicated that fluopyram-resistant mutants were positive cross-resistant to all six SDHI fungicides in this test but were still sensitive to fluazinam and tebuconazole.So the resistance risk of D.bryoniae to fluopyram was moderate.In addition,we found that the SdhB gene of low-resistant mutant XN30FR-1 had three new point mutations at positions K258N,A259P,and H277N.Medium-resistant mutant XN52FR-1 showed a mutation at position H277N and other mutants did not have any point mutation.
文摘Objective To evaluate the in vitro anti-diabetic effects of Bryonia dioica roots extracts,in-cluding water-acetone extracts and their ethyl acetate and butanol fractions,and chloroform-methanol extracts.Methods The total phenolic,flavonoid,flavonol,and saponin contents in the Bryonia dioica root extracts(chloroform-methanol extracts,water-acetone extracts and their ethyl acetate and butanol fractions)were determined using colorimetric methods with Folin-Ciocalteu,aluminum trichloride,and vanillin reagents,respectively.The in vitro anti-diabetic activity was evaluated by measuring the half-maximal inhibitory concentration(IC_(50))values of these root extracts againstα-amylase andα-glucosidase activities,evaluating their effects onα-amy-lase kinetics,quantifying the inhibition of bovine serum albumin(BSA)glycation using fluo-rometry to assess advanced glycation end products(AGE)production,and determining glu-cose uptake by isolated rat hemidiaphragm.Additionally,molecular docking analysis was conducted to investigate the binding affinity and interaction types between Bryonia dioica lig-ands(cucurbitacin B,bryogénin,vitexin,and isovitexin)and target enzymes,and a phyto-chemical-targets interaction network was constructed.Results Forα-amylase inhibition,ethyl acetate fraction demonstrated the most potent activi-ty(IC_(50)=145.95μg/mL),followed by chloroform-methanol extract(IC_(50)=300.86μg/mL).Water-acetone root extracts and their ethyl acetate and butanol fractions inhibited theα-glucosidase activity with IC50 values ranging from 562.88 to 583.90μg/mL.Both ethyl acetate and butanol fractions strongly inhibited non-enzymatic BSA glycation(IC_(50)=318.26 and 323.12μg/mL,respectively).The incubation of isolated rat hemidiaphragms with the ethyl acetate fraction(5 mg/mL)significantly increased glucose uptake(35.16%;P<0.0001),exceeding the effects of insulin(29.27%),chloroform-methanol extract(24.07%),and catechin(15.27%).Molecular docking revealed that cucurbitacin B exhibited the strongest docking scores againstα-amylase(-16.4 kcal/mol),andα-glucosidase(-14.2 kcal/mol).Compared with other ligands,isovitexin formed the maximum number of hydrogen bonds with theα-amylase active site residues(Asp300,Asp197,and Glu233),α-glucosidase residues(Ser13,Arg44,Met86,Gly10,Asp39,and Tyr131)and other residues(Arg195,Trp59,His299,and Tyr62).Network analysis identified 36 overlapping targets between Bryonia dioica phyto-chemicals and type 2 diabetes mellitus-associated genes,with cucurbitacins and polyphenols interacting withα-amylase,α-glucosidase,and Glut4 translocation pathway targets.Conclusion Bryonia dioica root extracts demonstrated promising in vitro anti-diabetic activi-ty through multiple mechanisms,including the inhibitory effect on digestive enzymes,pro-tein antiglycation potential,and enhancement of glucose uptake,suggesting their potential as a source for anti-diabetic drugs development.
