title: Antifungal Activity of a Synthetic Cationic Peptide against the Plant Pathogens Colletotrichum graminicola and Three Fusarium Species.
abstract: A small cationic peptide (JH8944) was tested for activity against a number of pathogens of agricultural crops. JH8944 inhibited conidium growth in most of the tested plant pathogens with a dose of 50 μg/ml, although one isolate of Fusarium oxysporum was inhibited at 5 μg/ml of JH8944. Most conidia of Fusarium graminearum were killed within 6 hours of treatment with 50 μg/ml of JH8944. Germinating F. graminearum conidia required 238 μg/ml of JH8944 for 90% growth inhibition. The peptide did not cause any damage to tissues surrounding maize leaf punctures when tested at a higher concentration of 250 μg/ml even after 3 days. Liposomes consisting of phosphatidylglycerol were susceptible to leakage after treatment with 25 and 50 μg/ml of JH8944. These experiments suggest this peptide destroys fungal membrane integrity and could be utilized for control of crop fungal pathogens.
authors.affiliation: Crop Bioprotection Research Unit, USDA Agricultural Research Service, Peoria, IL 61604-3902, USA.
authors.forename: Eric T
authors.initials: ET
authors.lastname: Johnson
authors.affiliation: Renewable Product Technology Research Unit, USDA Agricultural Research Service, Peoria, IL 61604-3902, USA.
authors.forename: Kervin O
authors.initials: KO
authors.lastname: Evans
authors.affiliation: Crop Bioprotection Research Unit, USDA Agricultural Research Service, Peoria, IL 61604-3902, USA.
authors.forename: Patrick F
authors.initials: PF
authors.lastname: Dowd
keywords: antifungal peptide; membrane-active mechanism; non-phytotoxic