8 Biotechnology and Bioinformatics of Endophytes …
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antipathogenic and plant growth capacities. The endophytic bacteria act as biocontrol
agents that synthesize VOCs as a part of their metabolism (Liu and Zhang 2015).
VOCs pass freely through biological membranes and may be released into the soil
or the atmosphere (Cappellari et al. 2019).
8.6.8 Competition for Space and Nutrients
The rhizospheric soil is very rich in carbon. Therefore, it represents a source of
attraction to diverse microbes, including phytopathogens (Ramamoorthy et al. 2001).
Biological control agents occupy similar niches as pathogens and gradually outcompete them for occupancy (Handelsman and Stabb 1996) and “precious” nutrients,
leading to a reduction in nutrient availability to phytopathogens (Thakur and Singh
2018).
8.6.9 Antibiosis and Antibiotics
Antibiosis is a mechanism by which the biocontrol agent produces several secondary
metabolites to inhibit or suppress pathogens (Haas and Défago 2005). Antibiotics
production is the main biocontrol mechanism employed by a variety of antagonistic
microbes in the rhizosphere. They are defined as a group of low-molecular weight
organic compounds that are effective in suppressing bacterial growth (Glick et al.
2007).
8.6.10 Detoxification and Degradation of Pathogens
Virulence Factors
Microbial pathogens could produce toxins aiming at inhibiting antagonistic microorganisms. Moreover, it was recently demonstrated that certain beneficial bacteria
could attenuate pathogen quorum-sensing abilities. Thus, they block virulence genes
expression, because bacterial phytopathogens require series of quorum-sensing
signals to activate their virulence factors (von Bodman et al. 2003).
8.6.11 Induced Systemic Resistance (ISR)
Induced systemic resistance (ISR) is a defense mechanism enhanced by microbial
endophytes to enhance the plant’s protective levels against a wide range of pathogens
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antipathogenic and plant growth capacities. The endophytic bacteria act as biocontrol
agents that synthesize VOCs as a part of their metabolism (Liu and Zhang 2015).
VOCs pass freely through biological membranes and may be released into the soil
or the atmosphere (Cappellari et al. 2019).
8.6.8 Competition for Space and Nutrients
The rhizospheric soil is very rich in carbon. Therefore, it represents a source of
attraction to diverse microbes, including phytopathogens (Ramamoorthy et al. 2001).
Biological control agents occupy similar niches as pathogens and gradually outcompete them for occupancy (Handelsman and Stabb 1996) and “precious” nutrients,
leading to a reduction in nutrient availability to phytopathogens (Thakur and Singh
2018).
8.6.9 Antibiosis and Antibiotics
Antibiosis is a mechanism by which the biocontrol agent produces several secondary
metabolites to inhibit or suppress pathogens (Haas and Défago 2005). Antibiotics
production is the main biocontrol mechanism employed by a variety of antagonistic
microbes in the rhizosphere. They are defined as a group of low-molecular weight
organic compounds that are effective in suppressing bacterial growth (Glick et al.
2007).
8.6.10 Detoxification and Degradation of Pathogens
Virulence Factors
Microbial pathogens could produce toxins aiming at inhibiting antagonistic microorganisms. Moreover, it was recently demonstrated that certain beneficial bacteria
could attenuate pathogen quorum-sensing abilities. Thus, they block virulence genes
expression, because bacterial phytopathogens require series of quorum-sensing
signals to activate their virulence factors (von Bodman et al. 2003).
8.6.11 Induced Systemic Resistance (ISR)
Induced systemic resistance (ISR) is a defense mechanism enhanced by microbial
endophytes to enhance the plant’s protective levels against a wide range of pathogens