Study On The Classification And Identification Of Antagonistic Starin 61239 And Its Biocontrol Effct

Apple valsa canker is a serious disease that threatens the branches of apple trees,caused by the infection of apple black rot fungi(Valsa mali Miyabe et Yamada),causing the fruit trees to cause cortical decay and necrosis.Recent studies have found that some species of Chaetomium have the ability to produce bioactive substances and prevent plant diseases,and have been developed into commodity preparations in some countries and regions.In this paper,the resistance of Chaetomium to Valsa mali was studied,and the following results were obtained:1.The experiment isolated from the healthy apple branches of the strain 61239,combined with morphological characteristics and molecular identification,identification of the strain for the spherical shell Chaetomium globsum.2.The C.globsum fungus 61239 and Valsa mali confrontation culture,resulting in antibacterial zone,pick up the mycelium of the antibacterial zone observed,found that the top of mycelium expansion.The results showed that the fermentation filtrate had a significant inhibitory effect on the growth of mycelial growth of apple tree rot,although the inhibition rate was decreased with the increase of dilution factor,the C.globsum fungus 61239 50 times dilution of the filtrate was still 70.90% inhibition after 5 days.3.The fermentation filtrate of C.globsum strain 61239 has a significant inhibitory effect on the conidial germination of Valsa mali.But with the fermentation filtrate dilution multiple increase,the inhibitory effect will decline.When the fermentation filtrate was diluted 5 times,the germination rate of the conidia was above 90%,and the microscopic observation showed that the fermentation filtrate of the bulbous strain 61239 reduced the volume of conidia.Indicating that the bulb production of bacteria in the metabolic process will produce real physiological substances,such substances on the apple rot fungi have a significant lethal effect and inhibit the growth effect.4.The biocontrol strain 61239 on the Apple valsa canker inoculation experiments showed that: only rotting fungi control group lesion diameter from 5mm average expansion to 30.2mm.And as long as the wound inoculated with bulb shell health bacteria,although at the same time inoculation of rot fungi,branches on the wound diameter is less than 5mm,and the wound edge callus,wound surface appear bulb production of fungi black pork,control effect reached 100%.5.The strain 61239 on the field of Apple valsa canker rot disease control experiments show that: in the apple harvest and dormant period in the apple tree rot of the scar at the application of bulb shell Health fungi 61239 wettable powder,the following year early spring rot.By investigating the recurrence of three orchards of the old scar,found that the recurrence rate of the old scar are more than 75%.Indicating that the use of spherical shell spores wettable powder can effectively prevent the recurrence of scar.Apple valsa canker is a serious disease that threatens the branches of apple trees,caused by the infection of apple black rot fungi(Valsa mali Miyabe et Yamada),causing the fruit trees to cause cortical decay and necrosis.Recent studies have found that some species of Chaetomium have the ability to produce bioactive substances and prevent plant diseases,and have been developed into commodity preparations in some countries and regions.