Submitted to: National American Phytopathology Meetings
Publication Type: Abstract Only
Publication Acceptance Date: March 20, 1997
Publication Date: N/A
Fusarium oxysporum f. sp. erythroxyli causes a vascular wilt of the narcotic plant Erythroxylum coca. Fruits of symptomatic and asymptomatic plants were collected in Hawaii (69 fruits) and Peru (202 fruits). Fruits were aseptically and individually divided into five parts (pedicel, pericarp, seed coat, endosperm, and cotyledons) and plated onto Komada's agar medium. In fruits from Peru, F. oxysporum was recovered from all parts of some fruits. F. oxysporum was isolated from 33% of the fruits and most isolates (35%) were from the seed coat. Slightly greater numbers of isolates were from symptomatic (57%) than from asymptomatic (43%) plants. Most isolates (59%) from Hawaii were from pedicels. In a greenhouse assay, 21 of 91 isolates tested were pathogenic to coca (6 from pedicel, 8 from pericarp, 4 from seed coat, 3 from endosperm). Most (76%) of the pathogenic isolates were originally from symptomatic plants. Based on RAPD Danalysis and VCG grouping, two subpopulations were recovered from Peru and one from Hawaii.