ABSTRACT
Because plants are rich sources of nutrients, microorganisms invade plant cells, where they may cause infectious diseases. Microorganisms can cause a large range of symptoms in most cultivated
9.1 Introduction .......................................................................................................................... 191 9.2 Plant Pathogen Interactions .................................................................................................. 192 9.3 Plant Pathogenic Bacteria ..................................................................................................... 192 9.4 Plant Disease Resistance ...................................................................................................... 192
9.4.1 Variations in Disease Resistance .............................................................................. 193 9.5 Plant Immune Systems ......................................................................................................... 193 9.6 Metabolic Substances in Defense Mechanisms .................................................................... 194
9.6.1 Secondary Metabolites in Defense Mechanisms ...................................................... 194 9.6.2 Secondary Metabolites against Bacteria .................................................................. 195
9.6.2.1 Terpenes ..................................................................................................... 195 9.6.2.2 Phenolic Compounds ................................................................................. 196 9.6.2.3 Sulfur-Containing Secondary Metabolites ................................................ 197 9.6.2.4 Nitrogen-Containing Secondary Metabolites ............................................ 199
9.7 Transgenic Engineered Secondary Metabolites ...................................................................200 9.8 Conclusion and Future Perspectives ..................................................................................... 201 Acknowledgment ........................................................................................................................... 201 References ...................................................................................................................................... 201
plants, which can be affected in different parts with various agronomic impacts (Lopez et al., 2003). Across large regions and many crop species, it is estimated that diseases typically reduce plant yields by 10% every year in more-developed nations, often exceeds 20% in less-developed nations, and are a negative factor in 15% of global crop production (Dangl et al., 2013).
