Identification And Biological Characteristics Of The Pathogen From Fig Anthracnosc And Screening Of Effective Fungicides

Fig anthracnose is a fig disease caused by C.gloeosporioides.Collecting the symptoms of Anhui field was collected and isolating 10 strains from fig leaf and diseased fruit were isolated by tissue separation method.Through the isolation and identification of pathogens,biological characteristics and effective fungicides screening,the environmental conditions of suitable growth and sporulation of fig anthracnose pathogen C.gloeosporioides were identified and three effective agents for inhibiting the growth of C.gloeosporioides were screened.The results of this study provide a reference for the occurrence,prevalence and prevention of fig anthracnose in orchard.The main findings are as follows:1.Isolation and identification of pathogenic bacteriaThe pathogenic fungi were isolated by the method of plant tissue separation,and 10 strains were purified by the method of single spore separation.The morphological observation of pathogenic fungi showed that the spores of pathogenic fungi were about 8.4-16.8 m in length and 3.5-5.5 m in width,oval in shape,transparent in color,with a transparent circle in the middle.The appressorium is irregular and brown.On pathogenic fungi of the internal transcribed spacer,(ITS)actin,(ACT)beta tubulin,(TUB-2)chitin synthase A,glyceraldehydes(CHS)phosphate dehydrogenase,(GAPDH)calmodulin,(CAL6)allele for clustering analysis,The phylogenetic tree of anthrax showed that the isolated pathogenic fungi were in the same branch with c.eosporioides,and the morphological observation showed that the pathogen was C gloeosporioides.2.Biological characteristics of fig anthraxThis test determined the optimal growth medium,optimum mycelial growth and spore production quantity temperature,pH value,lethal temperature of fig anthracnose pathogen and the utilization degree of pathogen to different carbon sources and nitrogen sources.The results show that the optimal culture mediums for Anthrax was potato sucrose agar medium,in glucose peptone agar medium was the most suitable for spore production,The mycelium of pathogen grew well between 20?-30? and the optimum temperature was 25?.Under 55? water bath after 10 min,pathogen can't grow.The optimum pH was 6,and the most suitable conditions for the spore production quantity was 3.0.The pathogen could make use of carbon sources such as maltose,sucrose,and nitrogen sources such as peptone,yeast extract and beef extract.3.Screening of effective agents for anthraxAccording to growth rate method and the toxic medium method,the inhibition of ndazim,benzoyl propiconazole,benzoyl azoxystrobin,tebuconazole,pyraclostrobin,phenylpropadiazole and prochloraz on the fig anthraces K7 strain were determined.Among them,phenylpropiconazole and prochloraz had the best inhibitory effect on the mycelial growth of pathogenic bacteria,with EC50 values of 0.0112 ?L/mL and 0.0130 ?L/mL,respectively;followed by carbendazim with an EC50 value of 0.0157 ?L/mL;Inhibitors such as benzoylpropanazole,benzopyrimidine,tebuconazole and pyraclostrobin have poor antibacterial effects,with EC50 values of 0.0607 ?L/mL,0.1019 ?L/mL,and 0.0166 ?L/mL,respectively.0.1308 ?L/mL.