声明
Table of contents
Abbreviations
ABSTRACT
摘要
Chapter 1 Research background
1．1 Biological control
1．1．1 Mechanisms used by biocontrol agents for plant disease management
1．2 Bacillus spp．as a biocontrol agent (BCA) and plant growth promoting rhizobacteria (PGPR)
1．2．1 Production of lipopeptides
1．2．2 Volatiles Organic Compounds(VOCs)
1．2．3 Extracellular products
1．3 Fusarium graminearum
1．3．1 The fungus Fusarium graminearum：Taxonomy，Pathology，and Ecology
1．3．2 Symptoms and infection process of F．graminearum on cereal crops
1．3．3 Formation of mycotoxins
1．3．4 FHB Disease management
1．4 Role of volatile organic compounds (VOCs) in fungal-bacterial interactions
1．5 Aims and objectives of the study
References
Chapter 2 Effect of Volatile Organic Compounds of Fusarium graminearum strain PH-1 on plant growth
Abstract
2．1 Introduction
2．2 MATERIALS AND METHODS
2．2．1 Effect of F．graminearum VOCs on seed germination
2．2．2 Effect of F．graminearum VOCs on plant growth
2．2．3 Identification of volatile compounds produced by F．graminearum
2．2．4 Effect of pure chemicals on Seed germination and plant growth
2．2．5 Effect of 2，4 Di tert-butyl phenol on plant growth
2．2．6 Statistical analysis
2．3 Results
2．3．1 VOCs produced by Fusarium graminearum has a negative impact on seed germination
2．3．2 VOCs produced by F．graminearum has a negative impact on plant growth
2．3．3 Identification of VOCs produced by F．graminearum
2．3．4 Pure chemical has an adverse effect on seed germination
2．3．5 Pure chemical 2，4 Di tert-butyl phenol (2，4 DTBP) have an adverse effect on plant growth
2．4 Discussion
2．5 Conclusion
References
Chapter 3 Fengycin Produced by Bacillus amyloliquefaciens FZB42 Inhibits Fusarium graminearum Growth and Mycotoxins Biosynthesis
Abstract
3．1 Introduction
3．2 MATERIALS AND METHODS
3．2．1 Bacterial and fungal strains and growth conditions
3．2．2 Construction of the AK1S mutant
3．2．3 Anti-fungal activity assay
3．2．4 Purification of fengycin from the AKlS mutant and MALDI-TOF MS analysis
3．2．5 Scanning electron microscopic observation of hyphal morphologies
3．2．6 Plant infection and Mycotoxin production assay
3．2．7 Statistical analysis
3．3 Results
3．3．1 Fengycin Produced by B．amyloliquefaciens FZB42 mutant AKIS Displayed Antagonistic Activity Against F．graminearum
3．3．2 Fengycin caused ultrastructural changes of F．graminearum hyphae
3．3．3．Fengycin Reduced F．graminearum virulence and Mycotoxins Biosynthesis
3．4 Discussion
3．5 Conclusion
References
Chapter 4 Volatile Organic Compounds of Fusarium graminearum：Mode of Defensive Mechanism of Bio-control Bacteria
Abstract
4．1 Introduction
4．2 Material and methods
4．2．1 Microorganisms and growth conditions
4．2．2 Evaluation of the bactericidal effects of fungal VOCs against biocontrol bacteria
4．2．4 Effect of Fungal VOCs on Biofilm formation of bioeontroi Bacillus strains
4．2．5 Effect of F．graminaerum VOCs on the motility of biocontrol bacterial
4．2．6 Effect of F．graminearum VOCs on root colonization
4．2．7 Scanning electron microscopy
4．2．8 Expression analysis of important bacterial genes under the influence of VOCs of F．graminearum
4．2．9 Production of Extracellular enzymes under the influence of Fungal VOCs
4．2．10 Expression analysis of exoenzymes genes under the influence of VOCs of F．graminearum
4．2．11 Effect of Fusarium graminearum VOCs on biocontrol potential of Bacillus spp
4．2．12 In Planta Bio-control Assay
4．2．13 Statistical analysis
4．3 Results
4．3．1 Bactericidal effects of fungal VOCs against biocontrol bacteria
4．3．2 Antibacterial activity of pure chemical volatiles on Bacillus
4．3．3 Effect of Fungal VOCs on Biofilm formation
4．3．4 Effect of F．graminearum VOCs on motility of biocontrol bacterial
4．3．5 Effect of F．graminearum VOCs on root colonization potential of biocontrol bacteria
4．3．6 Fusarium graminearum VOCs caused morphological changes in Bacillus observed by SEM
4．3．7 Expression analysis of bacterial genes related to Motility and Biofilm enzymes
4．3．8 Production of Extracellular enzymes under the influence of Fungal VOCs
4．3．9 Expression profiling of bacterial genes related to extracellular enzymes
4．3．10 Effect of Fusarium graminearum VOCs on biocontrol potential of Bacillus
4．3．11 Disease control impairment
4．4 Discussion
4．5 Conclusion
Reference
Appendix
Publications
ACKNOWLEDGEMENTS
南京农业大学;
