Efficacy of several biocontrol agents against leaf blight in garland chrysanthemum

Abstract

The efficacies of several biocontrol agents against leaf blight caused by Cercospora chrysanthemi in garland chrysanthemum were investigated. Fungal mycelial disks were incubated on potato dextrose agar (PDA) plates spread with suspensions of each biocontrol agent, and were assayed for mycelial growth. Six kinds of Bacillus subtilis and one B. amyloliquefaciens agent potently inhibited C. chrysanthemi mycelial growth. The efficacies of these agents against leaf blight in potted garland chrysanthemum plants were tested. Of the agents, two of the B. subtilis agents and B. amyloliquefaciens stably reduced the disease severity relative to the control and showed promise for the control of leaf blight in garland chrysanthemum.