Journal of Phytopathology (2016) 164, 801-810

Yukie Kawasaki, Claudia Nischwitz, Michelle M. Grilley, Justin Jones, Jason D. Brown and Jon Y. Takemoto (2016)
Production and application of syringomycin E as an organic fungicide seed protectant against Pythium damping-off
Journal of Phytopathology 164 (10), 801-810
Abstract: Syringomycin E (SRE) is a cyclic lipodepsinonapeptide with potent antifungal activity and is produced by certain strains of Pseudomonas syringae pv. syringae. In this study, its potential as an organic-compatible agrofungicide and vegetable seed treatment against the soilborne pathogen Pythium ultimum var. ultimum was examined. A variant of P. syringae pv. syringae strain B301D with enhanced SRE-producing capabilities was isolated and grown in a bioreactor with SRE yields averaging 50 mg/l in 40 h. SRE was extracted and purified through a large-scale chromatography system using organic-compatible processes and reagents. The minimum concentrations of the purified product required to inhibit 50 and 90% of P. ultimum oospore germination were determined as 31.3 and 250 μg/ml, respectively. Drench treatment of cucumber seeds in P. ultimum-infested potting medium (500 oospores/g) with 50 μg/ml SRE or water with no SRE resulted in 90.2 ± 4.5% and 65.7 ± 4.6% germination rates, respectively. Seed coating with 0.03% (w/w) SRE allowed 65.7 ± 4.6% seedlings to germinate on naturally infested soil while 100.0 ± 0.0% of non-coated seeds were unable to germinate due to Pythium infection. Organic-compatible and scalably produced SRE is potentially a novel organic fungicide seed protectant.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Claudia Nischwitz

Research topic(s) for pests/diseases/weeds:
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Globisporangium ultimum	Cucumber (Cucumis sativus)