Study of the Biological Characteristics of Bacillus amyloliquefaciens subsp. plantarum 71 in NOVO TECH 888 and Its Effect on Fusarium Wilt in Strawberry Plants in vitro

The biological characteristics of Bacillus amyloliquefaciens subsp. plantarum 71, obtained from the commercial product NOVO TECH 888 (Atomes F.D. Inc., Canada), were studied. Morphological and biochemical identification revealed that the bacterium is rod-shaped, Gram-positive, motile, catalase-positive, urease-producing, spore-forming, and facultatively aerobic. It is capable of degrading starch, gelatin, and pectin, and is tolerant to salt concentrations ranging from 2-10% NaCl. The bacterium proliferates actively within a temperature range of 25 to 50 °C, with an optimal growth temperature of 35 °C, indicating its thermophilic nature. It can grow across a broad pH range (pH 4, 7, and 10), demonstrating its adaptability to diverse environmental conditions. The bacterial cell concentration in 1 mL of the commercial product was determined to be 5.32 × 109 CFU. The bacterium retained its viability in the commercial product for three years without any significant decrease in its activity. Additionally, it was confirmed that the bacterium was unaffected by copper in the form of copper sulfate pentahydrate (Cu2SO4·5H2O) or copper hydroxide Cu (OH)2, nor by sulfur under controlled laboratory conditions. The efficacy of this bacterium in controlling the vascular wilt fungus Fusarium oxysporum f. sp. fragariae, isolated from strawberry plants, was also evaluated. The bacterium inhibited fungal mycelial growth on nutrient agar plates and induced morphological deformities in the fungal mycelium. These results indicate the promising potential of B. amyloliquefaciens as a biocontrol agent for Fusarium wilt disease in strawberries, making it a viable option for use in organic agriculture.