|HEWAVITHARANA, SHASHIKA - Washington State University|
Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2017
Publication Date: 12/1/2017
Citation: Hewavitharana, S.S., Mazzola, M. 2017. Effect of different Gramineae carbon inputs on efficacy of ASD for control of Macrophomina phaseolina in strawberry. Phytopathology. 107(Suppl.5), 46.
Technical Abstract: Anaerobic soil disinfestation (ASD), using either orchard grass (GR) or wheat shoots (WH) as the carbon input, was examined for the control of M. phaseolina in strawberry. The pathogen was artificially infested at a density of 2.5 sclerotia g-1 soil. Treatments included in the study were ASD with orchard grass (GR), wheat leaf residues (WH) or rice bran (RB) at 20 t ha-1, no treatment control (NTC), and pasteurized control (PC). The effect of soil volatiles produced during the ASD process on M. phaseolina hyphal growth was determined. Post-treatment headspace O2 content, soil pH, fungal growth, and strawberry cv. Albion crown infection were assessed. Soils attained anaerobic state based on the headspace O2 content in response to all ASD treatments by the end of the incubation period irrespective of the carbon source. Soil pH was lowest in ASD-RB soil. Volatiles produced in the GR and WH treatments significantly reduced fungal colony growth compared to RB and NTC, but fungal growth resumed upon transfer to fresh media indicating that the compounds were fungistatic. Among ASD treatments, M. phaseolina crown infection was the lowest in WH. Pathogen DNA detected in crowns was significantly reduced by GR, WH, and PC treatments relative to RB and NTC.