7 Tropical Endophytic Bacillus Species …
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(BNF) of endophytic species was assessed in E. urograndis roots using culturedependent and culture-independent techniques. The data suggests that Eucalyptus
benefit from BNF, with many abundant genera closely related to nitrogen-fixing
bacteria. Under N-depleted media, 25% of the bacterial isolates are able to grow and
present the nif H gene. As the most dominant members were related to Bacillus, the
conclusion is that the naturally high abundance of these bacteria makes them the
most promising bacterial inoculant for plant growth promotion.
In addition to high P fixation and aluminum toxicity, tropical agriculture suffers
the effect of the continuous attack of plant pathogens as these environments present
ideal water, temperature, and nutrient conditions for their proliferation. The identification and development of locally adapted biological control agents are extremely
pertinent as native strains have greater adaptability, performance, and suitability than
introduced microorganisms. Considering the seriousness of diseases in tropical agriculture, native B. amyloliquefaciens, B. cereus, B. megaterium, and B. pumilus strains
from tropical soils of Trinidad were isolated and characterized as antibiotic lipopeptide producers, such as iturin, bacillomycin, bacilysin, fengycin, surfactin, and zwittermycin. Testing of these Bacillus species against pathogens such as Alternaria,
Fusarium, Ralstonia, Cercospora, and Colletotrichum revealed greater antagonistic
activity of all lipopeptide produced by B. amyloliquefaciens strains as compared
with non-producers being promising for the development of bioagents suitable for
disease management in tropical conditions (Saravanakumar et al. 2018). Antifungal
lipopeptides inhibiting plant pathogens as F. moniliforme as well as inducing the
up-regulation of pathogenesis-related (PR) genes of host plants (systemic acquired
resistance) were also reported in endophytic Bacillus spp. isolated from maize from
Indian popcorn and yellow dent corn. The presence of antifungal iturin A, fengycin,
and bacillomycin were also detected using MALDI-TOF mass spectrometry (Gond
et al. 2015).
In tropical ecosystems, the ability of endophytic microorganisms to colonize the
internal tissues of plants suggests an ecological advantage. Mangrove forests, typical
tropical ecosystems situated between land and sea, are among the most productive
and diverse communities worldwide, particularly in Brazil, Indonesia, and Australia.
These ecosystems are important sources of endophytic microorganisms with biotechnological potential, which deserves further studies (Sebastianes et al. 2017). Interesting, Bacillus is the most frequent genus, comprising 42 and 28% of the endophytic
isolates from plant species from two mangrove systems in Brazil. In other study,
Bacillus spp. isolated from mangrove trees in Malaysia show efficacy in promoting
seedling growth in rice. The inoculation of rice seeds with endophytic strains of B.
cereus and B. amyloliquefaciens significantly increased the root and shoot length,
suggesting that endophytic bacteria from mangrove trees can increase the fitness of
rice seedlings under controlled conditions (Deivanai et al. 2014). Other studies evaluated the enzyme production of endophytic Bacillus from mangrove forest in India
and Brazil. Enzymes protease and endoglucanase activity are observed in 70% of
the isolates and bacteria exhibit the highest activity rates for amylase, esterase, and
endoglucanase. In addition, the antimicrobial activity against important pathogens,
165
(BNF) of endophytic species was assessed in E. urograndis roots using culturedependent and culture-independent techniques. The data suggests that Eucalyptus
benefit from BNF, with many abundant genera closely related to nitrogen-fixing
bacteria. Under N-depleted media, 25% of the bacterial isolates are able to grow and
present the nif H gene. As the most dominant members were related to Bacillus, the
conclusion is that the naturally high abundance of these bacteria makes them the
most promising bacterial inoculant for plant growth promotion.
In addition to high P fixation and aluminum toxicity, tropical agriculture suffers
the effect of the continuous attack of plant pathogens as these environments present
ideal water, temperature, and nutrient conditions for their proliferation. The identification and development of locally adapted biological control agents are extremely
pertinent as native strains have greater adaptability, performance, and suitability than
introduced microorganisms. Considering the seriousness of diseases in tropical agriculture, native B. amyloliquefaciens, B. cereus, B. megaterium, and B. pumilus strains
from tropical soils of Trinidad were isolated and characterized as antibiotic lipopeptide producers, such as iturin, bacillomycin, bacilysin, fengycin, surfactin, and zwittermycin. Testing of these Bacillus species against pathogens such as Alternaria,
Fusarium, Ralstonia, Cercospora, and Colletotrichum revealed greater antagonistic
activity of all lipopeptide produced by B. amyloliquefaciens strains as compared
with non-producers being promising for the development of bioagents suitable for
disease management in tropical conditions (Saravanakumar et al. 2018). Antifungal
lipopeptides inhibiting plant pathogens as F. moniliforme as well as inducing the
up-regulation of pathogenesis-related (PR) genes of host plants (systemic acquired
resistance) were also reported in endophytic Bacillus spp. isolated from maize from
Indian popcorn and yellow dent corn. The presence of antifungal iturin A, fengycin,
and bacillomycin were also detected using MALDI-TOF mass spectrometry (Gond
et al. 2015).
In tropical ecosystems, the ability of endophytic microorganisms to colonize the
internal tissues of plants suggests an ecological advantage. Mangrove forests, typical
tropical ecosystems situated between land and sea, are among the most productive
and diverse communities worldwide, particularly in Brazil, Indonesia, and Australia.
These ecosystems are important sources of endophytic microorganisms with biotechnological potential, which deserves further studies (Sebastianes et al. 2017). Interesting, Bacillus is the most frequent genus, comprising 42 and 28% of the endophytic
isolates from plant species from two mangrove systems in Brazil. In other study,
Bacillus spp. isolated from mangrove trees in Malaysia show efficacy in promoting
seedling growth in rice. The inoculation of rice seeds with endophytic strains of B.
cereus and B. amyloliquefaciens significantly increased the root and shoot length,
suggesting that endophytic bacteria from mangrove trees can increase the fitness of
rice seedlings under controlled conditions (Deivanai et al. 2014). Other studies evaluated the enzyme production of endophytic Bacillus from mangrove forest in India
and Brazil. Enzymes protease and endoglucanase activity are observed in 70% of
the isolates and bacteria exhibit the highest activity rates for amylase, esterase, and
endoglucanase. In addition, the antimicrobial activity against important pathogens,