A recent BAAR scientific study evaluated ZeroTol 2.0 by BioSafe Systems, LLC, in controlling Alternaria Blight on red zinnias. Results showed that ZeroTol 2 – a liquid concentrate, activated peroxide chemistry for controlling a broad range of pathogens – works on contact. The study showed it increased the overall vigor of the zinnia by 15 percent and reduced the percentage of leaf area with Alternaria blight symptoms by 63% compared to the untreated plants.Alternaria Blight of zinnia is caused by the fungus Alternaria zinnia. It is the most common disease on zinnias and can affect stems, foliage, and flowers. Affected leaves show brown spots, which coalesce as the disease progresses resulting in dry brown lesions. On flowers, the pathogen can produce dark brown spots that are unsightly in appearance.