Inhibitory Effect Of Traditional Chinese Medicine And Biogas Slurry On Two Strains Of Panax Notoginseng Root Rot Pathogens

Panax notoginseng is an important traditional Chinese medicine（TCM）in China,with promoting blood circulation by removing blood stasis and relieve swelling effect.During the planting process of P.notoginseng,due to the dark and humid growth environment,the continuous cropping obstacle and root rot of P.notoginseng are very serious.Therefore,the quality and quality of P.notoginseng medicinal materials are seriously affected,resulting in the obstruction of the industrialization of P.notoginseng.In this study,Fusarium oxysporum and Fusarium solani in the root rot pathogens of P.notoginseng were taken as research objects.The effective components of TCM were extracted by different methods.Four kinds of TCM with better comprehensive antifungal effect were selected from eight kinds of TCM,and combined with biogas slurry of the antifungal effect on two pathogenic fungi were studied.TCM extraction methods include water extraction and ethanol extraction,and combined with biogas slurry combined antifungal methods include:TCM alone antifungal,different TCM compound antifungal,single TCM and biogas slurry combined antifungal,TCM compound liquid and biogas slurry combined antifungal.The antifungal mechanism was analyzed by the inhibitory effect of each solution on the mycelial growth,spore inhibition rate,minimum inhibitory concentration（MIC）and virulence of pathogenic fungi.The main results of this study are as follows:（1）The inhibitory effects of water and ethanol extracts of 8 kinds of TCM on two strains of root rot pathogens of P.notoginseng were determined,and four kinds of TCM with good comprehensive antifungal effects were selected:Coptis chinensis,Phellodendron chinense,Lonicerae Japonicae and Portulaca oleracea;and combine them with biogas slurry in different proportions to inhibit fungi.The results showed that the best combination ratio of TCM and biogas slurry was 1:20.⑵The inhibitory effect of water extract and ethanol extract of single TCM on the mycelial growth,spore inhibition rate,virulence and MIC of the two pathogenic fungi were different.The inhibitory effect on F.oxysporum from strong to weak is as follows:C.chinensis ethanol extract>L.Japonicae water extract>P.oleracea water extract>C.chinensis water extract>P.oleracea ethanol extract>P.chinense water extract>P.chinense ethanol extract>L.Japonicae ethanol extract;the inhibitory effect on F.solani from strong to weak is as follows:C.chinensis ethanol extract>P.oleracea ethanol extract>P.oleracea water extract>L.Japonicae ethanol extract>C.chinensis water extract>L.Japonicae water extract>P.chinense water extract>P,chinense ethanol extract.⑶The inhibitory effect and virulence effect of water extract compound solution on the two pathogenic fungi were generally stronger than that of ethanol extract compound solution,and the inhibitory effect was more stable with the decrease of concentration.The water extract compound combination of P.chinense+L.Japonicae had the best antifungal effect and toxicity against F.oxysporum and F.solani,and the maximum antifungal rates were 75.82%and 81.88%respectively,EC₅₀were3.00×10^-4mg/m L and 1.00×10^-17mg/m L respectively,MIC were 2.00×10^-3mg/m L;The maximum inhibition rate of ethanol extract compound solution on the two pathogenic fungi was less than 65%,and the inhibition rate decreased rapidly with the decrease of concentration.（4）The inhibition effect of single TCM combined with biogas slurry on the mycelial growth,spore inhibition rate,virulence and MIC of the two pathogenic fungi were stronger than that of biogas slurry alone.The inhibitory effect on F.oxysporum from strong to weak is:L.Japonicae ethanol extract+biogas slurry>C.chinensis ethanol extract+biogas slurry>C.chinensis water extract+biogas slurry>L.Japonicae water extract+biogas slurry>P.oleracea water extract+biogas slurry>P.chinense water extract+biogas slurry>P.chinenseethanol extract+biogas slurry>P.oleracea ethanol extract+biogas slurry,the inhibitory effect on F.solani from strong to weak was as follows:L.Japonicae ethanol extract+biogas slurry>C.chinensis water extract+biogas slurry>L.Japonicae water extract+biogas slurry>P.chinense water extract+biogas slurry>P.chinense ethanol extract+biogas slurry>C.chinensis ethanol extract+biogas slurry>P.oleracea water extract+biogas slurry>P.oleracea ethanol extract+biogas slurry;（5）The inhibitory effect of the combination of TCM compound with fluid and biogas slurry on the two pathogenic fungi were generally better than that of TCM compound with fluid.The combination of ethanol extract and biogas slurry had the best inhibitory effect on the mycelial growth of F.oxysporum,and the toxic effect was stronger,and the antifungal effect was stable with the decrease of concentration;The toxic effect of water extract combined with biogas slurry on F.solani was generally stronger than that of ethanol extract combined with biogas slurry.Conclusion:Each TCM alone antifungal,each TCM compound liquid antifungal,and each TCM combined with biogas slurry antifungal had different effects on the inhibition on pathogenic fungi,indicating that the combination of different TCM and biogas slurry may had synergistic,additive and antagonistic effects on the inhibitory effects of pathogenic fungi.The results of this study provided theoretical basis for the control of P.notoginseng root rot and the development of biological pesticides.