Status of Macrophomina phaseolina on Strawberry in California and Preliminary Characterization of the Pathogen

Authors

Steven T. Koike, University of California Cooperative ExtensionFollow
Renee S. Arias, USDA, Agricultural Research ServiceFollow
Cliff S. Hogan, USDA, Agricultural Research Service
Frank N. Martin, USDA, Agricultural Research Service
Thomas R. Gordon, University of California, Davis

Document Type

Article

Date of this Version

2016

Citation

INTERNATIONAL JOURNAL OF FRUIT SCIENCE 2016, VOL. 16, NO. S1, 148–159

Comments

© 2016 Taylor & Francis

This document is a U.S. government work and is not subject to copyright in the United States.

http://dx.doi.org/10.1080/15538362.2016.1195313

Abstract

Macrophomina crown and root rot has become a significant soil-borne disease issue in California. For many locations in the state, the disease is associated with fields that are no longer pre-plant, flat field fumigated with methyl bromide + chloropicrin. Inoculation experiments indicated that some differences in strawberry cultivar susceptibility to Macrophomina phaseolina were seen a short time after the inoculation, but as disease progressed such differences did not persist. Preliminary characterization studies of Macrophomina phaseolina isolates from strawberry indicated that such isolates may have a host preference for strawberry. Macrophomina phaseolina isolates from watermelon, thyme, and apple failed to cause disease in strawberry. Five cover crop species, which can be rotated with strawberry, did not develop disease when inoculated with strawberry isolates. In preliminary analysis using simple sequence repeat markers, isolates obtained from strawberry formed a separate group compared to isolates recovered from other known Macrophomina phaseolina hosts.