The Inhibitory Effect Of Three Kinds Of Chinese Herbal Medicine On Plant Pathogenic Fungi

Botanical pesticides is the pesticide extract from certain parts of the plant or effective components which has insecticidal and bactericidal action to extract effective components.It has the advantages of safety,no toxicity,no pollution,is the need and the direction of the development of modern agriculture and play an important role in controlling fungi of plant.Extract natural compound with antifungal activity from plants become an important way to get the current new pesticide discovery.Polygonum cuspidatum,coptis root,Ligusticum are traditional Chinese medicine,has the functions of promoting blood circulation,clearing away heat,promoting diuresis,analgesia,eta.They are widely used in Chinese medicines.This paper takes the three kinds of Chinese medicinal as materials,extract its effective material with different solvent,and its antibacterial property of five kinds of pathogenic fungi common were studied,It provide scientific basis for the development of new antimicrobial agents.The present study is composed of the following three parts.1.The extraction and antifungal activity of the effective component from three kinds of Chinese herbal medicineObjective Extraction of effective components of three kinds traditional Chinese medicine,and determined its inhibitory effect on five kinds of plant pathogenic fungi.Methods Parallel extraction With four different solvents(water,ethanol,acetone,ethyl acetate)on three kinds of traditional Chinese medicine(Polygonum cuspidatum,coptis root,Ligusticum),take five plant common pathogenic fungi(Fusarium graminearum,Rhizoctonia solani,Bipolaris maydis,Botrytis cinerea,rape Sclerotinia sclerotiorum)as the target,determination the antibacterial activity of three kinds of traditional Chinese medicine extracts.Results In addition to the ethyl-acetate extract of Ligusticum was failed,11 kinds of extracts were obtained.The best inhibitory effect against Fusarium graminearum Schw,the inhibition of growth is ethanol extract of Rhizoma Coptidis,and its half inhibitory concentration is 3.66mg/mL;best inhibitory effect against Rhizoctonia solani,the inhibition of growth is ethylacetate extract of Polygonum cuspidatum,and its half inhibitory concentration is 6.81mg/mL;best inhibitory effect against Helminthosporium maydis,the inhibition of growth is ethyl acetate extract of Rhizoma Coptidis,and its half inhibitory concentration is 0.07mg/mL;bestinhibitory effect against Botrytis cinerea,the inhibition of growth is ethanol extract of Rhizoma Coptidis,and its half inhibitory concentration is 0.13mg/mL;best inhibitory effect against Sclerotinia Sclerotiorum,the inhibition of growth is the aqueous extract of Rhizoma Coptidis,and its half inhibitory concentration is 0.16mg/mL.Conclusion Extract of coptis can be considered as bacteriostatic agent to Production for its good antibacterial ability on those common pathogenic fungi,and the extracts of Coptidis can be used as the fungal inhibitor indepth research and commercial development by inhibit all 5 kinds of pathogenic fungi and showing strong antifungal activity.2.Preliminary study of inhibition mechanism on five kinds of plant pathogenic fungiObjective Inhibition mechanism of extracts which have the best inhibitory effect onof five kinds of bacteria were measured.Methods determination of extract on the inhibition of fungal growth through the determination of spore production rate,spore germination,hyphal morphology observation.determine the effect of fungal cell membrane permeability extract By measuring the conductivity of solution,extracellular polysaccharide,extracellular protein content.Results After treatment with the ethanol extract of Rhizoma Coptidis on Fusarium graminearum Schw,Mycelium Increased branches,elongated internode,hyphae became finer.The conductivity increased with the increase of the concentration of the extract,and the content of polysaccharide and protein of the extracellular increased with the concentration of solution.After treatment with the ethyl acetate extract of Polygonum cuspidatum on Rhizoctonia solani,The conductivity increased with the increase of the concentration of the extract,and the content of polysaccharide and protein of the extracellular increased with the concentration of solution.The ethyl acetate extract of Rhizoma Coptidis had obvious inhibitory effect on the formation,germination of the spores.After the treatment of Helminthosporium maydis,hyphae became finer,more branches,internode elongated tapering,conidiophore initiation of germ tube becomes larger.The conductivity,content of polysaccharide protein increased with the increase of the concentration of solution.The mycelium shape significantly thinner,lighter in color after the treatment of the ethanol extract of Rhizoma Coptidis on Botrytis cinerea,and The conductivity,content of polysaccharide protein increased with the increase of the concentration of solution.The aqueous extract of Rhizoma Coptidis had some inhibitory effect on spore formation and germination of Sclerotinia Sclerotiorum,The mycelia had no obvious changes after treatment.Theconductivity increases with increasing osmotic concentration,polysaccharides and proteins of the extracellular volume increases.Conclusion The extract of the ethanol extract of Rhizoma Coptidis enlarged the cell membrane permeability of Fusarium graminearum.The ethyl acetate extract of Polygonum cuspidatum enlarged the cell membrane permeability of Rhizoctonia solani.The ethyl acetate extract of Rhizoma Coptidis can inhibit the formation of Bipolaris maydis spore germination of Helminthosporium maydisand enlarge the permeability of cell membrane.The extract of the ethanol extract of Rhizoma Coptidis enlarged the cell membrane permeability of Botrytis cinerea.The aqueous extract of Rhizoma Coptidis can inhibit the formation of Sclerotinia Sclerotiorum spore germination and enlarged the permeability of cell membrane.3.Component analysis of the extractsObjective In order to find the main antibacterial substances of the three kinds of chinese medicine,we determined the main componets in the extract.Methods Total content of flavonoids,polysaccharide,polyphenol and protein was determined by using the colorimetric method;The accurate,stable method was established to detemine the content of resveratrol,emodin,emodin,berberine,jatrorrhizine,Baron Martin,ferulic acid.Results The content of emodin from extract of Polygonum cuspidatum were 0.17,0.96,0.15,3.39%.Little difference in active ingredient content from Polygonum cuspidatum;Differences between the active ingredient content of each extract of Rhizoma Coptidis are little;Testing failed to detected the content of ligustilide from Ligusticum sinense and the content of ferulic acid were 0.73,3.02,1.64%,rest components have little differences on their content.Conclusion Inhibitory effect of traditional Chinese medicine extract may be synergistic effect of the active substances.emodin can be used as an important pointer antibacterial activity in Polygonum cuspidatum extracts and Ferulic acid can be as important substance antibacterial activity in Ligusticum extracts.