Laboratory mutants of Sclerotinia sclerotiorum(Lib)de Bary,resistant to boscalid,have been extensively characterized.However,the resistance situation in the lettuce field remains largely elusive.In this study,among th...Laboratory mutants of Sclerotinia sclerotiorum(Lib)de Bary,resistant to boscalid,have been extensively characterized.However,the resistance situation in the lettuce field remains largely elusive.In this study,among the 172 S.sclerotiorum isolates collected from asparagus lettuce field in Jiangsu Province,China,132 isolates(76.74%)exhibited low-level resistance to boscalid(Bos^(LR)),with a discriminatory dose of 5μg mL-1.In comparison to the boscalid-sensitive(BosS)isolates,most Bos^(LR)isolates demonstrated a slightly superior biological fitness,as evidenced by data on mycelial growth,sclerotium production and pathogenicity.Moreover,most Bos^(LR)isolates showed comparable levels of oxalic acid(OA)accumulation,increased exopolysaccharide(EPS)content and reduced membrane permeability when compared to the BosS isolates.Nevertheless,their responses to distinct stress factors diverged significantly.Furthermore,the effectiveness of boscalid in controlling Bos^(LR)isolates on radish was diminished compared to its efficacy on BosS isolates.Genetic mutations were identified in the SDH genes of Bos^(LR)isolates,revealing the existence of three resistant genotypes:I(^(A11V)at SDHB,SDHB^(A11V)),II(^(Q38R)at SDHC,SDHC^(Q38R))and III(SDHB^(A11V)+SDHC^(Q38R)).Importantly,no cross-resistance was observed between boscalid and other fungicides such as thifluzamide,pydiflumetofen,fluazinam,or tebuconazole.Our molecular docking analysis indicated that the docking total score(DTS)of the type I resistant isolates(1.3993)was lower than that of the sensitive isolates(1.7499),implying a reduced affinity between SDHB and boscalid as a potential mechanism underlying the boscalid resistance in S.sclerotiorum.These findings contribute to an enhanced comprehension of boscalid’s mode of action and furnish valuable insights into the management of boscalid resistance.展开更多
Nutrient and stress factor 1(Nsf1),a transcription factor containing the classical Cys2-His2(C_(2)H_(2))zinc finger motif,is expressed under non-fermentable carbon conditions and in response to salt stress in Saccharo...Nutrient and stress factor 1(Nsf1),a transcription factor containing the classical Cys2-His2(C_(2)H_(2))zinc finger motif,is expressed under non-fermentable carbon conditions and in response to salt stress in Saccharomyces cerevisiae.However,the role of Nsf1 in filamentous fungi is not well understood.In this study,the orthologue of Nsf1 was investigated in Fusarium graminearum(named FgNsf1),a causal agent of Fusarium head blight(FHB).The functions of FgNsf1 were evaluated by constructing a FgNSF1 deletion mutant,designated asΔFgNsf1,and its functional complementation mutantΔFgNsf1-C.Gene deletion experiments showed that the mycelial growth rate,asexual and sexual reproduction ofΔFgNsf1 were significantly reduced,but the pigment production ofΔFgNsf1 was remarkably increased compared with the PH-1 andΔFgNsf1-C.In addition,the tolerance ofΔFgNsf1 to osmotic pressures,cell wall-damaging agents and oxidative stress increased significantly.Sensitivity tests to different fungicides revealed thatΔFgNsf1 exhibited increased sensitivity to carbendazim(MBC)and tebuconazole,and enhanced tolerance to fludioxonil and iprodione than PH-1 andΔFgNsf1-C.The virulence ofΔFgNsf1 to wheat coleoptiles and flowering wheat heads were dramatically decreased,which was consistent with the decrease in the yield of deoxynivalenol(DON).All of these defects were restored by target gene complementation.These results indicated that FgNsf1 plays a crucial role in vegetative growth,asexual and sexual reproduction,stress responses,fungicide sensitivity,and full virulence in F.graminearum.展开更多
The mixed noise in the acquisition process of pulse wave signals will affect the signal analysis, how to effectively eliminate the noise and complete the pulse wave analysis has important practical significance. In th...The mixed noise in the acquisition process of pulse wave signals will affect the signal analysis, how to effectively eliminate the noise and complete the pulse wave analysis has important practical significance. In this paper, empirical mode decomposition(EMD) and ensemble empirical mode decomposition(EEMD) were used to realize scale decomposition of pulse wave signals to obtain intrinsic mode function(IMF). A band-pass filter was implemented according to the characteristic time scale parameters of the IMF. After filtering and reconstruction, the pulse wave denoising was completed. The denoising effects of EMD, EEMD and wavelet transform were compared in terms of mean square error and signal-to-noise ratio. The result shows that EMD and EEMD are better than wavelet transform, and the effects are similar. Further comparing the Hilbert-Huang spectrum of EMD and EEMD, it can be seen that EEMD can not only avoid mode mixing, but also facilitate the analysis of pulse wave signals.展开更多
基金supported by the Jiangsu Provincial Key Research and Development, China (BE2021361)the Jiangsu Agriculture Science and Technology Innovation Fund ((CX(21)2037 and CX(22)3072))the National Natural Science Foundation of China (31672065)。
文摘Laboratory mutants of Sclerotinia sclerotiorum(Lib)de Bary,resistant to boscalid,have been extensively characterized.However,the resistance situation in the lettuce field remains largely elusive.In this study,among the 172 S.sclerotiorum isolates collected from asparagus lettuce field in Jiangsu Province,China,132 isolates(76.74%)exhibited low-level resistance to boscalid(Bos^(LR)),with a discriminatory dose of 5μg mL-1.In comparison to the boscalid-sensitive(BosS)isolates,most Bos^(LR)isolates demonstrated a slightly superior biological fitness,as evidenced by data on mycelial growth,sclerotium production and pathogenicity.Moreover,most Bos^(LR)isolates showed comparable levels of oxalic acid(OA)accumulation,increased exopolysaccharide(EPS)content and reduced membrane permeability when compared to the BosS isolates.Nevertheless,their responses to distinct stress factors diverged significantly.Furthermore,the effectiveness of boscalid in controlling Bos^(LR)isolates on radish was diminished compared to its efficacy on BosS isolates.Genetic mutations were identified in the SDH genes of Bos^(LR)isolates,revealing the existence of three resistant genotypes:I(^(A11V)at SDHB,SDHB^(A11V)),II(^(Q38R)at SDHC,SDHC^(Q38R))and III(SDHB^(A11V)+SDHC^(Q38R)).Importantly,no cross-resistance was observed between boscalid and other fungicides such as thifluzamide,pydiflumetofen,fluazinam,or tebuconazole.Our molecular docking analysis indicated that the docking total score(DTS)of the type I resistant isolates(1.3993)was lower than that of the sensitive isolates(1.7499),implying a reduced affinity between SDHB and boscalid as a potential mechanism underlying the boscalid resistance in S.sclerotiorum.These findings contribute to an enhanced comprehension of boscalid’s mode of action and furnish valuable insights into the management of boscalid resistance.
基金This work was supported by the National Key Research&Development Program of China(2016YED0201007,2018YFD0201201 and 2018YFD0201000)the National Natural Science Foundation of China(31672065)+1 种基金the Agricultural Science and Technology Projects of Jiangsu Province,China(BE2018378,BA2018039,PZCZ201715,CX(19)3003,and CX(18)2005)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX18_0670).
文摘Nutrient and stress factor 1(Nsf1),a transcription factor containing the classical Cys2-His2(C_(2)H_(2))zinc finger motif,is expressed under non-fermentable carbon conditions and in response to salt stress in Saccharomyces cerevisiae.However,the role of Nsf1 in filamentous fungi is not well understood.In this study,the orthologue of Nsf1 was investigated in Fusarium graminearum(named FgNsf1),a causal agent of Fusarium head blight(FHB).The functions of FgNsf1 were evaluated by constructing a FgNSF1 deletion mutant,designated asΔFgNsf1,and its functional complementation mutantΔFgNsf1-C.Gene deletion experiments showed that the mycelial growth rate,asexual and sexual reproduction ofΔFgNsf1 were significantly reduced,but the pigment production ofΔFgNsf1 was remarkably increased compared with the PH-1 andΔFgNsf1-C.In addition,the tolerance ofΔFgNsf1 to osmotic pressures,cell wall-damaging agents and oxidative stress increased significantly.Sensitivity tests to different fungicides revealed thatΔFgNsf1 exhibited increased sensitivity to carbendazim(MBC)and tebuconazole,and enhanced tolerance to fludioxonil and iprodione than PH-1 andΔFgNsf1-C.The virulence ofΔFgNsf1 to wheat coleoptiles and flowering wheat heads were dramatically decreased,which was consistent with the decrease in the yield of deoxynivalenol(DON).All of these defects were restored by target gene complementation.These results indicated that FgNsf1 plays a crucial role in vegetative growth,asexual and sexual reproduction,stress responses,fungicide sensitivity,and full virulence in F.graminearum.
文摘The mixed noise in the acquisition process of pulse wave signals will affect the signal analysis, how to effectively eliminate the noise and complete the pulse wave analysis has important practical significance. In this paper, empirical mode decomposition(EMD) and ensemble empirical mode decomposition(EEMD) were used to realize scale decomposition of pulse wave signals to obtain intrinsic mode function(IMF). A band-pass filter was implemented according to the characteristic time scale parameters of the IMF. After filtering and reconstruction, the pulse wave denoising was completed. The denoising effects of EMD, EEMD and wavelet transform were compared in terms of mean square error and signal-to-noise ratio. The result shows that EMD and EEMD are better than wavelet transform, and the effects are similar. Further comparing the Hilbert-Huang spectrum of EMD and EEMD, it can be seen that EEMD can not only avoid mode mixing, but also facilitate the analysis of pulse wave signals.
