Wet Seed Treatments for the Control of Bacterial Fruit Blotch of Watermelon. D. L. Hopkins, University of Florida, Central Florida Research and Education Center, 5336 University Avenue,Leesburg 34748. J. D. Cucuzza and J. C. Watterson, Petoseed Co., Woodland Research Station, 37437 StateHighway 16, Woodland, CA 95695. Plant Dis. 80:529. Accepted for publication I February 1996. Copyright 1996 The American Phytopathological Society. DOI: 10.1094/PD-80-0529.

The bacterium causing fruit blotch of watermelon was transmitted in seeds from fruit that had the typical water-soaking symptom; from fruit that had small, restricted, necrotic lesions; and from symptomless fruit adjacent to typically symptomatic fruit. Storage of seed at 12°C for 12 months did not reduce the level of seed transmission. Fermentation of seeds in watermelon juice and debris prior to washing and drying reduced the level of seed transmission from symptomatic fruit from 61% to less than 1%. Treatment of washed seeds from symptomatic fruit with 1% CaOCl₂ for 15 min was relatively ineffective in reducing seed transmission, but 1% HCI for 15 min was as effective as fermentation. Fermentation of seeds for 24 to 48 h followed by 1% HCl or 1% CaOCl₂ treatment for 15 min prior to washing and drying were the most effective treatments for eliminating bacterial contamination of watermelon seeds. These treatments did not adversely affect seed germination.