Biological Characteristics And Pathogenic Enzyme Activity Studies On Pathogenic Fungi Causing Sophora Japonica Canker

In recent years,Canker disease of Chinese scholar tree has been widespread in Liaocheng and surrounding areas,which has affected the production of the seedlings and urban greening of the locust trees seriously,resulting in significant economic losses.Therefore,it is urgent to study the etiology and pathogenesis of canker disease in Chinese scholar tree and to guide the disease prevention.Taking Chinese scholar tree as the target plant,with its canker pathogens for target fungi,the law of survey,carried out the isolation and identification of pathogenic fungi,studied the biological characteristics of pathogen,and from enzyme levels,studies its pathogenic mechanism,the results indicate:(1)The pathogenesis of canker disease in Chinese scholar tree was studied by means of symptom and severe investigation.The occurrence of canker disease is concentrated in one or two years.In spring and autumn,the peak period of the disease occurred.The growth period of the disease occurred in March,and the peak period was between May to June and September to October respectively.Sunburn can aggravate the occurrence of canker disease;Frostbite is an important factor affecting the incidence of Chinese scholar tree.(2)Liaocheng region canker pathogens of Chinese scholar tree are mainly include five kinds through morphology,pathogenicity and methods of molecular biology identification.They are Fusarium lateritium,F.chlamydosporum,F.decemcellulare,Dothiorella ribis and Phoma glomerata.F.lateritium,Dothiorella ribis and P.glomerata are dominant pathogens.(3)Biological characteristics research showed that the pathogens of canker disease in Chinese scholar tree canker have different ecological and nutritional characteristics,the optimal culture medium for mycelia growth and sporulation is PDA and optimum temperature is 20~25?,the illumination conditions are not strictly,to adapt to a wide range of pH value;The suiTab.carbon source of different pathogens is different,nitrate nitrogen and organic nitrogen promote the growth and production of mycelia,and ammonium nitrogen inhibits the growth and sporulation of mycelia.(4)The pathogenesis of different pathogenic fungi of canker disease was studied by colorimetry.Cell wall degradation enzymes is one of the important pathogenic factor.Cellulase,hemicellulase,lignin enzymes,protease and pectinase a variety of pathogenic enzyme collaborative work when pathogenic fungi caused disease pathogen infect pagoda tree trunks;When the locust ulcer disease was caused by F.decemcellulare,lignin was the main pathogenic enzyme,and the lignin was decomposed to cause the disease,among which the lactase was one of the main pathogenic enzymes.When the ulcer was caused by F.lateritium,the celulase was the main pathogenic enzyme system,Cx enzyme and betaglucosidase were the main factors.When caused by D.ribis,protease was the main pathogenic enzyme system.When it was caused by P.glomerata,hemicellulose was the main pathogenic enzyme system.