great efficiency, environmental safety, and lack of harmful effects on mammals and
non-target organisms. In Iran, likewise in other parts of the world, due to the success of
Bt in biological control, research on this bacterium is being continued to discover novel
Bt strains and toxins, find a broader spectrum of activity and eventually develop
efficient bio-pesticide based on Bt.
10.2 Insect Pathogenic Bacteria
Based on the industrial activities and/or scientific interests’ point of view, the most
important entomopathogenic bacteria in the biological control of pests are mainly in
the genera of the family Bacillaceae (B. thuringiensis and Lysinibacillus sphaericus),
Paenibacillaceae (Paenibacillus spp. and Brevibacillus lateropporous),
Entrobacteriaceae (Photorhabdus spp., Xenorhabdus spp., Serratia spp. and Yersinia
entomophaga), Pseudomonaceae (Psedomonas entomophila) and Neisseriaceae (JuratFuentes and Jackson 2012; Ruiu 2015). Among the mentioned entomopathogenic
bacteria, the most widely used and well-studied is the Bacillus genus.
10.3 The Genus Bacillus
Bacterial species within the genus Bacillus represent the most successful microbial
control agents to date. B. thuringiensis with other bacteria such as B. mycoides,
B. pseudomycoides, B. weihensteohanensis, B. cereus and B. anthracis belong to the
B. cereus group (Helgason et al. 2000). Due to the high degree of genetic similarity,
B. cereus sensu stricto, Bt, B. anthracis are allocated into the B. cereus sensu lato
group (Helgason et al. 2000; Bavykin et al. 2004). The presence of the insecticidal
genes in the Bt plasmids differentiates this bacterium from the other members of the
B. cereus sensu lato group, B. anthracis (the causative agent of anthrax) and
B. cereus (an opportunistic human pathogen causing food poisoning) (Thorne
1993). Although the insecticidal activity of some B. cereus isolates has been
previously reported (Strongman et al. 1997; Selvakumar et al. 2007; Chatterjee
et al. 2010), due to the presence of some toxins toxic to vertebrates, the commercialization of this bacterium in biological control of pests has not yet been developed. Different strains of L. sphaericus produce mosquitocidal toxins toxic to
Dipterans (Baumann et al. 1991). Commercial products based on the L. sphaericus
target mosquitos and black files (Jurat-Fuentes and Jackson 2012). In the Bacillus
genus, different strains of B. thuringiensis showed great potential for control of
agricultural, forestry, medical and veterinary pests. Thus, Bt is the most commonly
commercialized and used bio-insecticide worldwide.
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A. Khorramnejad et al.
non-target organisms. In Iran, likewise in other parts of the world, due to the success of
Bt in biological control, research on this bacterium is being continued to discover novel
Bt strains and toxins, find a broader spectrum of activity and eventually develop
efficient bio-pesticide based on Bt.
10.2 Insect Pathogenic Bacteria
Based on the industrial activities and/or scientific interests’ point of view, the most
important entomopathogenic bacteria in the biological control of pests are mainly in
the genera of the family Bacillaceae (B. thuringiensis and Lysinibacillus sphaericus),
Paenibacillaceae (Paenibacillus spp. and Brevibacillus lateropporous),
Entrobacteriaceae (Photorhabdus spp., Xenorhabdus spp., Serratia spp. and Yersinia
entomophaga), Pseudomonaceae (Psedomonas entomophila) and Neisseriaceae (JuratFuentes and Jackson 2012; Ruiu 2015). Among the mentioned entomopathogenic
bacteria, the most widely used and well-studied is the Bacillus genus.
10.3 The Genus Bacillus
Bacterial species within the genus Bacillus represent the most successful microbial
control agents to date. B. thuringiensis with other bacteria such as B. mycoides,
B. pseudomycoides, B. weihensteohanensis, B. cereus and B. anthracis belong to the
B. cereus group (Helgason et al. 2000). Due to the high degree of genetic similarity,
B. cereus sensu stricto, Bt, B. anthracis are allocated into the B. cereus sensu lato
group (Helgason et al. 2000; Bavykin et al. 2004). The presence of the insecticidal
genes in the Bt plasmids differentiates this bacterium from the other members of the
B. cereus sensu lato group, B. anthracis (the causative agent of anthrax) and
B. cereus (an opportunistic human pathogen causing food poisoning) (Thorne
1993). Although the insecticidal activity of some B. cereus isolates has been
previously reported (Strongman et al. 1997; Selvakumar et al. 2007; Chatterjee
et al. 2010), due to the presence of some toxins toxic to vertebrates, the commercialization of this bacterium in biological control of pests has not yet been developed. Different strains of L. sphaericus produce mosquitocidal toxins toxic to
Dipterans (Baumann et al. 1991). Commercial products based on the L. sphaericus
target mosquitos and black files (Jurat-Fuentes and Jackson 2012). In the Bacillus
genus, different strains of B. thuringiensis showed great potential for control of
agricultural, forestry, medical and veterinary pests. Thus, Bt is the most commonly
commercialized and used bio-insecticide worldwide.
404
A. Khorramnejad et al.