Antagonist effects of Bacillus spp. strains against Fusarium graminearum for protection of durum wheat ( Triticum turgidum L. subsp. durum )

Abstract

Bacillus species are attractive due to their potential use in the biological control of fungal diseases. Bacillus amyloliquefaciens strain BLB369, Bacillus subtilis strain BLB277, and Paenibacillus polymyxa strain BLB267 were isolated and identified using biochemical and molecular (16S rDNA, gyrA, and rpoB) approaches. They could produce, respectively, (iturin and surfactin), (surfactin and fengycin), and (fusaricidin and polymyxin) exhibiting broad spectrum against several phytopathogenic fungi. In vivo examination of wheat seed germination, plant height, phenolic compounds, chlorophyll, and carotenoid contents proved the efficiency of the bacterial cells and the secreted antagonist activities to protect Tunisian durum wheat (Triticum turgidum L. subsp. durum) cultivar Om Rabiia against F. graminearum fungus. Application of single bacterial culture medium, particularly that of B. amyloliquefaciens, showed better protection than combinations of various culture media. The tertiary combination of B. amyloliquefaciens, B. subtilis, and P. polymyxa bacterial cells led to the highest protection rate which could be due to strains synergistic or complementary effects. Hence, combination of compatible biocontrol agents could be a strategic approach to control plant diseases.

Genome Mining of the Lipopeptide Biosynthesis of Paenibacillus polymyxa E681 in Combination with Mass Spectrometry: Discovery of the Lipoheptapeptide Paenilipoheptin

“…[17,18] Fusaricidinsa re distinguished by potent activities against fungi of the genera Fusarium and Aspergillus as well as Gram-positive bacteria. They functiona se fficient biocontrol agentsa nd are, for example, effective against Fusarium strains [52,53] and Phytophthora blight infectioni nr ed pepper. [54] Polymyxins are the lead compounds of P. polymyxa strains.…”

Heterologous expression and periplasmic secretion of an antifungal Bacillus amyloliquefaciensBLB369 endo‐β‐1,3‐1,4‐glucanase in Escherichia coli

“…B. amyloliquefaciens BLB369 was frequently found in soils, so it was isolated from rhizosphere soil sample for its antifungal activity (Zalila‐Kolsi et al., ). E. coli Top10 grown in Luria–Bertani (LB) broth medium while recombinant strains harbouring a plasmid grown in LB medium supplemented with ampicillin (100 μg/ml).…”

Multistrain versus single-strain plant growth promoting microbial inoculants - The compatibility issue

“…As a result, all the synthetic mixtures consistently showed a better effi cacy in exerting the desirable eff ect in an additive or synergistic manner. In another study, the mixture of compatible B. amyloliquefaciens strain BLB369, B. subtilis strain BLB277 and Paenibacillus polymyxa strain 267 has been shown to stimulate wheat seed germination and exhibit better effi cacy in controlling head blight caused by Fusarium graminearum than treatments with the individual strains or mixtures of two-strain combination (Zalila-Kolsi et al, 2016). The combined application of three compatible (colonization levels of cotton stems were similar for each strain) biocontrol strains on cotton roots, B. subtilis YUPP-2, P. polymixa YUPP-8 and Paenibacillus xylanilyticus YUPP-12, revealed better eff ect in controlling Verticillium dahliae in cotton than their individual application (Yang et al, 2013).…”