In vitro studies of biofilm-forming Bacillus strains, biocontrol agents isolated from the maize phyllosphere

Draft genome sequences of two biocontrol agents isolated from the maize phyllosphere: Bacillus subtilis strain EM-A7 and Bacillus velezensis strain EM-A8

“…Chemotaxis allows bacteria to swarm across solid surfaces such as leaves and colonize them [ 31 ]. Under different environmental conditions (nutrient agar and different LED lights), EM-A7 and EM-A8 were able to swim and swarm [ 15 , 32 ]. Their genomes include genes efp (similar to elongation factor P), hag (flagellin), swrA (swarming motility protein) and yczE (integral membrane protein).…”

“…More precisely, these conditions affected the robustness of their biofilm, as demonstrated by the morphological phenotypes of their colonies. As described in Fessia et al [ 15 ], complex colonies were creamy and convex, had lobed irregular edges, and numerous wrinkles and veins spreading from the center to the edges. Less complex colonies were small, smooth, and round, with well-defined edges.…”

“…It facilitates colonization and survival on the leaf surface, and may promote either beneficial or harmful interactions with host plants, depending on the nature of the bacteria within it. We observed in vitro that biofilm formation and motility were modified in EM-A7 and EM-A8 by changing conditions of temperature, water potential, growth medium, and time [ 15 ]. More precisely, these conditions affected the robustness of their biofilm, as demonstrated by the morphological phenotypes of their colonies.…”

Adding Metal Ions to the Bacillus mojavensis D50 Promotes Biofilm Formation and Improves Ability of Biocontrol

“…The culture medium and culture time could also impact the biofilm formation of Bacillus spp. [16]. Glycerol, as a carbon source, and Ca 2+ and Mg 2+ have been reported to have a substantial effect on biofilm formation [15].…”

“…The three Bacillus spp. strains which could form biofilm were isolated to protect maize from pathogens, the temperature, culture medium, and culture time, which could influence the biofilm formation and thus further impact the biocontrol effect of these strains [16]. The application of phenylalanine could promote the biofilm formation of Meyerozyma caribbica and improved its biocontrol efficacy [17].…”