Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 1, 2001
Publication Date: June 1, 2001
Sweetpotato roots, cvs. Beauregard and Hernandez, were inoculated with a spore suspension (10(^6) spores/ml) of Rhizopus stolonifer using four injury types: puncture, impact bruise, scrape and broken end plus a non- injured control. Roots were stored at 13 to 15 C and disease incidence was evaluated 10 days after inoculation. The same experiment was conducted at 4- to 6-week intervals during a 9- to 11-month storage period in 1999 and 2000. Virtually no decay occurred for the first 30 to 60 days of storage. Injuring roots by the impact bruise method resulted in the highest levels of decay (80-100%) for both cultivars, peaking between 60 and 175 days. This was followed by a sharp decline in disease incidence for the same injury types. Roots injured by the broken end or scrape methods produced a variable response depending on the cultivar and the year. Decay incidence from both broken end and scrape injuries increased between 200 and 325 days in 1999, but this trend did not repeat in 2000. Disease incidence was generally greater in the broken end injury than in the scrape injury.