The Research Of The Pinus Sylvestris Red Blight Pathogen And Its Biological Control Technology

In this paper,we collected,separated,purifiedt and identificated the Pinus sylvestris red blight pathogenic from the internship MaoEr mountain forest farm,TongLiao big green ditch nature reserve in Inner Mongolia and JiLin baicheng.Though confirmed the Pinus sylvestnis red blight pathogenic we solved a problem which the Pinus sylvestnis red blight pathogenic was not settled for a long time.After that,we studied the biological characteristics of the Pinus sylvestris red blight pathogenic.Base on the structure of folicolous fungal community in Pinus sylvestnis in campus,we screened out antagonistic strains which has potential of development by the tablet confrontation experiment,and through the test in the woods,we laid a foundation for the biocontrol of Pinus sylvestris red blight.The major results as follows:1,We identified the Pinus sylvestris red blight pathogen which was Pestalotiopsis citrina(MeAipine)Nag Raj using both the combination of morphology and molecular biology method.And the GenBank accession No.KR065415 of it is.2,Through the biological characteristics experiment,we found the optimum growth temperature of the pathogen Pestalotiopsis citrina(MeAipine)Nag Raj is 22?,and the Pestalotiopsis citrina(MeAipine)Nag Raj has a strong adaptability for pH,it can grow in a range of pH from 4.5 to 9.2 1,and the hyphae grow fastest at pH 6.2 then the other pH.We also found that the Pestalotiopsis citrina(MeAipine)Nag Raj grow best on the medium which use the glucose as carbon source,while it grow fastest on the medium which use the peptone.Under the condition of darkness,the hyphae of Pestalotiopsis citrina(MeAipine)Nag Raj grow fastest,and under the condition of poikilothermal it can sporulation easily.The spore of Pestalotiopsis citrina(MeAipine)Nag Raj can germinate at the range of 10 to 30?,and at 15? the germination rate of the spore is highest,it can be 90.5%,while as the temperature increased the germination rate was decline.Moreover,when the relative humidity was 100%(water drop),the germination rate of the Pestalotiopsis citrina(MeAipine)Nag Raj is highest,,it can reach 83.21%,but when the relative humidity is under 80%the spores were totally stop germinated.And in nutrient solution with 2%glucose,the germination rate of the Pestalotiopsis citrina(MeAipine)Nag Raj is highest,it can reach 87.4%.All the above results shown that the germination rate of the Pestalotiopsis citrina(MeAipine)Nag Raj,The spore germination rate is highly affected by the components in nutrient solution.3,Based on the research of the community of Pinus sylvestris folicolous fungal,we concluded that the folicolous fungal species is rich,a total of 25 species of fungi was isolated.Among them,the number of Deuteromycotina species is the largest,the number of ascomycetes is second and the number of zygomycetes is minimum.The dominant species in Deuteromycotina is Penicillium sp.,Alternaria sp.,Paecilomyces sp.and Pestalitioposis sp..the separation rate of them were 19.7%,15.2%,15.5%and 15.2%respectively.Species of folicolous fungal were increased while the age of Pinus sylvestris was increase,we isolated 12 fungi species from the la Pinus sylvestris,16 fungi species from the 2a Pinus sylvestris,and 18 fungi species from the 3a Pinus sylvestris.4,Antagonistic experiment between 11 selected biocontrol fungi and Pestalotiopsis citrina(MeAipine)Nag Raj,shown that Trichoderma longibrachiatum has the highest inhibitory effect of the pathogen hyphae,the inhibition rate was 72.81%,the Chaetomium cruentum and Chaetomium indicum also have higher inhibitory effect of the pathogen hyphae,the inhibition rate were 49.16%and 42.36%respectively.The three fungus all have a inhibitory effect of Pestalotiopsis citrina(MeAipine)Nag Raj,the inhibition rate were all above 40%.According to the inhibition rate,coefficient of antagonism and the covered index degree of pathogenic we finally found three fungi(Trichoderma longibrachiatum,Chaetomium cruentum and Chaetomium indicum)which can effectively restrain the Pestalotiopsis citrina(MeAipine)Nag Raj.5,The three biocontrol fungi culture filtrate all have inhibitory effect of both the growth of Pestalotiopsis citrina(MeAipine)Nag Raj and the germinate of its spore,but the inhibition rate of them has a larger gap,especially the MQ3(Chaetomium cruentum)which has the highest inhibition rate to the growth of Pestalotiopsis citrina(MeAipine)Nag Raj,the inhibition rate was 73.48%when the content of culture filtrate was 50%The MQ2(Chaetomium indicum)has the highest inhibitory effect to the germinate of the spore,the inhibition rate was more than 98%after 24 h cultured.6,Three biocontrol fungi were tested in filed on controlling the Pestalotiopsis citrina(MeAipine)Nag Raj.The result shown that the three fungi all have control effect on the Pestalotiopsis citrina(MeAipine)Nag Raj,and the control effect of these fungi were different.And we also found that inoculated the mixing of the three fungi before the pathogen has the best control effect,the control efficiency was 90.61%.While if we inoculated the pathogen before the biocontrol fungi,the control efficiency were not so good.Especially when we inoculated the mixing of the three biocotrol fungi after the pathogen,the control efficiency was only 4.76%.All above shown that the screening biocontrol fungi have great prevention effect but poor treatment effect.