Wet seed treatment with peroxyacetic acid for the control of bacterial fruit blotch and other seedborne diseases of watermelon

ABSTRACT Prevention of seed transmission of Acidovorax avenae subsp. citrulli into the transplant house or field is the most effective control of bacterial fruit blotch of watermelon currently available. Peroxyacetic acid was evaluated as a disinfectant that might efficaciously eradicate A. avenae subsp. citrulli from contaminated seed and also be efficacious against other seed-transmitted diseases of watermelon. Peroxyacetic acid at low concentrations eliminated A. avenae subsp. citrulli, Fusarium oxysporum, and Didymella bryoniae from microbial suspensions. Treatments of seed contaminated with A. avenae subsp. citrulli and D. bryoniae with peroxyacetic acid at 1,600 μg/ml and higher for 30 min were effective in preventing seed transmission of bacterial fruit blotch and gummy stem blight. Hydrochloric acid treatments at 10,000 μg/ml, while effective in eliminating seed transmission to watermelon seedlings, can adversely affect seed germination, especially with triploid seed. Efficacious dosages of peroxy...