Double Nickel 55 is a broad-spectrum preventative biofungicide for control or suppression of fungal and bacterial plant diseases. The active ingredient of Double Nickel 55 is a naturally occurring strain (D747) of the beneficial rhizobacterium Bacillus amyloliquefaciens, which colonizes roots, leaves, and other plant surfaces. D747 rapidly colonizes plant root hairs, leaves, and other surfaces, preventing establishment of disease-causing fungi and bacteria. Double Nickel 55 can be applied alone or in combination and/or rotation with chemical fungicides as a tool for integrated disease management in agricultural crops, ornamental and nursery plants, and turfgrass, in accordance with the most restrictive of those label limitations and precautions. Double Nickel 55 offers a valuable tool for management of resistance to chemical fungicides through its multiple and unique modes of action. Double Nickel 55 can be applied up to and including the day of harvest.