向日葵黃萎病內生生防菌的篩選及其防治.pdf

1、 分類號 S482.7 學校代碼 10129 U D C 632 學 號 2012202065 向日葵黃萎病內生生防菌的篩選及其防治 Screening on Antifungal Endo-bacterium and Control of Sunflower V

2、erticillium Wilt 申 請 人：閆 潔 學科門類：農 學 學科專業(yè)：農藥學 研究方向：生物農藥的研制與開發(fā) 指導教師：周洪友 教授 論文提交日期：二〇一五年六月Screening on Antifungal Endo-bacterium and Control of Sunflower Verticillium Wilt Abstract Verticillium wilt is a serious vascular

3、 disease caused by a soil borne pathogen Verticilliu daliae in sunflower. It usually occurs in the main producing areas of sunflower. It is difficult to control because of little research work on occurrence and epidemic

4、regularity. In this study, the biocontrol endophyte were isolated form stems and roots of health sunflower tissue in Hohhot, Bayannur, Chifeng city, Ningxia, Shanxi province and the inhibition effects, colonization level

5、, biological characteristics, synergistic effects with fungicide were studied. The results showed as following. Total of 132 strains were abtained including 124 bacteria, 5 fungi and 3 actinomycetes. The strains XT1-4 an

6、d GY3-6 showed the strongest inhibition effects, and the inhibition zone were 12.4 mm and 10.6 mm wide in plates. The strains XT1-4 and GY3-6 were identified as Bacillus atrophaeus by morphological, physiological, bioche

7、mical characteristics, and 16S rDNA sequence analysis. The strains XT1-4 and GY3-6 could colonize and move in roots, stems and leaves of sunflower by soaking seed and pouring root. The biological characteristics of stra

8、ins XT1-4 and GY3-6 were determined. In results, the most optimum incubation conditions were 8 of pH value, 32 ℃ of tempreture, 24 h incubating time, and used sucrose and peptone as carbon and nitrogen resourse, put 50 m

9、l laquid medium per 250 ml flask. By testing the synergy of biocontrol bacteria isolated with fungicide, the strains XT1-4 and GY3-6 could be used for mixing with fungicide, and enhanced the capacity of prevention and co

10、ntrol to this diseases. By comparing methods of inoculation, both the leaf-paint assay and root-dipping method could accurately and rapidly evaluate pathogenicity of Verticillium dahliae to sunflower in laborotary. Key W

11、ords: Verticillium dahliae；Antifungal endo-bacterium；Bacillus atrophaeus；Synergism Directed by: Professor. ZHOU Hongyou Applicant for Master degree: YAN Jie （pesticide science) (Agricultural College, Inner Mongolia Ag