Evaluation of seed treatments for the eradication of Acidovorax avenae subsp citrulli from melon and watermelon seeds

Acidovorax avenae subsp. citrulli, the causal agent of bacterial fruit blotch of watermelon (Citrullus lanatus), is a serious seed-borne pathogen. To determine the effectiveness of several treatments to eradicate it from seeds, healthy triploid watermelon seed lots were spiked with naturally infected watermelon and melon seeds harvested from three separate diseased fruits. Of the eight treatments studied, only the use of acidic electrolyzed water for 30 min eradicated the pathogen from seeds without reducing seed germination or seedling establishment. Treatment with Clorox at 50 degrees C for 20 min, Tsunami 100 for 30 min, or acidified cupric acetate at 50 degrees C for 20 min eradicated the pathogen but significantly (P = 0.05) reduced seed germination and (or) seedling establishment (emergence). The other treatments either failed to eradicate the pathogen or reduced seed germination.