Rhizobacteria and their potential to control Fusarium verticillioides: effect of maize bacterisation and inoculum density

Abstract

Fusarium verticillioides is the most important seed transmitted pathogen that infects maize. It produces fumonisins, toxins that have potential toxicity for humans and animals. Control of F. verticillioides colonisation and systemic contamination of maize has become a priority area in food safety research. The aims of this research were (1) to characterise the maize endorhizosphere and rhizoplane inhabitant bacteria and Fusarium spp., (2) to select bacterial strains with impact on F. verticillioides growth and fumonisin B1 production in vitro, (3) to examine the effects of bacterial inoculum levels on F. verticillioides root colonisation under greenhouse conditions. Arthrobacter spp. and Azotobacter spp. were the predominant genera isolated from maize endorhizosphere and rhizoplane at the first sampling period, whilst F. verticillioides strains showed the greatest counts at the same isolation period. All F. verticillioides strains were able to produce fumonisin B1 in maize cultures. Arthrobacter globiformis RC5 and Azotobacter armeniacus RC2, used alone or in a mix, demonstrated important effects on F. verticillioides growth and fumonisin B1 suppression in vitro. Only Azotobacter armeniacus RC2 significantly reduced the F. verticillioides root colonisation at 10(6) and 10(7) CFU g(-1) levels under greenhouse conditions.

Antagonistic interactions between fungal rice pathogenFusarium Verticillioides (Sacc.) Nirenberg andTrichoderma harzianum Rifai

“…Later studies reported the ability of Bacillus subtilis to reduce rhizoplane and endorhizosphere F. verticillioides colonization at all inoculum and maize root levels tested, and suggested that the combination Enterobacter cloacae and Microbacterium oleovorans had the potential for the biological control of F. verticillioides as a maize seed inoculant (Cavaglieri et al, 2005a(Cavaglieri et al, , 2005b. Arthrobacter globiformis demonstrated important effects on F. verticillioides growth and fumonisin B1 suppression in vitro (Cavaglieri et al, 2005c).…”

In vitro influence of bacterial mixtures on Fusarium verticillioides growth and fumonisin B1 production: effect of seeds treatment on maize root colonization

“…The inhibition of F. verticillioides root colonization by individual rhizobacterial strains used in this study has previously been demonstrated (Cavaglieri et al. 2004c).…”

Cucumber Rhizosphere Microbial Community Response to Biocontrol Agent Bacillus subtilis B068150

“…Colonization of roots and soils through adding bio-control agent is considered a prerequisite for successful biological control [47,48]. B. subtilis B068150 strain, originally isolated from surface sterilized roots of cucumber plants, inhibited the cucumber Fusarium wilt [38].…”

“…Application of biocontrol agent directly into soils to control plant diseases was shown to have no negative impact on other organisms or on biogeochemical cycles [7,48,56]. One of the objectives described in this study was to elucidate the influence of B. bacillus B068150 on the native microbial communities in the cucumber rhizosphere.…”