Effects Of Cold Atmospheric Plasma On Inactivation,Growth And DON Biosynthesis In Fusarium Spp.

Fusarium spp.is one of the most destructive plant pathogenic fungus worldwide,which could not cause many devastating crop diseases with huge economic losses,but also produce mycotoxins with sever adverse effects on human and livestock health.Recently,cold atmospheric plasma(CAP)has gained much interest as a promising approach to control fungi and mycotoxins.However,the inactivation efficiency and mechanism of CAP against plant pathogenic fungi,and its application in vivo were still rarely reported.No information is available on the effects of CAP on mycotoxin biosynthesis.Herein,this study investigated the influence of CAP on spore inactivation,mycelial growth and deoxynivalenol(DON)biosynthesis of Fusarium spp.both in vitro and on wheat grains.The research work presented here can be categorized into four parts:(1)Detection of reactive species in CAP and CAP-treated liquids.The results show that CAP generated various reactive oxygen and nitrogen species,including atomic oxygen(O),nitric oxide(NO),hydroxyl radical(·OH),singlet oxygen(1O2),hydrogen peroxide(H2O2),nitrate(NO3-),nitrite(NO2-),endowing the water with oxidizing and acidic property.(2)Assessment of antifungal effect of CAP.3-min CAP treatment effectively inactivated the spores of four major Fusarium strains ranging from 2 to 6 log10 reduction.Meanwhile,CAP had marked inhibitory effects on spore germination and mycelial growth in vitro.(3)Analysis of inactivation mechanism and effects of CAP on DON biosynthesis in F.graminearum.The inactivation mechanism analysis reveals that CAP causes membrane destruction,intracellular ROS accumulation and mitochondrial membrane depolarization,inducing cell apoptosis or necrosis dependent on CAP treatment time.Moreover,CAP inhibited DON biosynthesis in F.graminearum via reducing acetyl-Co A production and down-regulating TRI genes expression.(4)Artificial inoculation experiment.Both survival rate of F.graminearum spores on wheat grains and the DON levels in F.graminearum artificially infected wheat grains decreased in a treatment-time-dependent mannert.The lesion length in infected coleoptiles also reduced in a treatment-time-dependent mannert.The artificial inoculation test verified that CAP could inactivate fungal spores,reduce DON production in wheat grains,and reduce pathogenicity of F.graminearum in coleoptiles.Overall,these findings provide comprehensive insights into the inactivation efficacy and mechanism of CAP against Fusarium spp.,which promotes the application of CAP in controlling fungal pathogens and mycotoxins contamination in cereals and plants.