Potential for using Fusarium to control Fusarium disease in forest nurseries

Abstract

The taxon Fusarium oxysporum contains a complex of fungi that are very important pathogens of many plant species worldwide, including seedlings grown in forest nurseries. All members of this complex appear very similar morphologically, and can often be differentiated only on the basis of genetic analyses. Strains of F. oxysporum may be pathogenic or nonpathogenic and both types often occupy the same environments and readily infect plant roots. Because of their similar requirements, nonpathogenic strains of F. oxysporum have been exploited as biological controls of pathogenic Fusarium strains on several types of crops. Although nonpathogenic strains infect plants, they do not induce disease symptoms. All previous nonpathogenic F. oxysporum strains have been obtained from, and used for, particular agricultural systems. We have obtained several isolates that are nonpathogenic on conifer seedlings and are genetically distinct from highly virulent isolates. Three of these are currently being tested on container Douglas-fir seedlings within a greenhouse to evaluate their efficacy for controlling root disease caused by virulent F. oxysporum isolates.

Citation

James, Robert L.; Dumroese, R. Kasten. 2007. Potential for using Fusarium to control Fusarium disease in forest nurseries. In: Riley, L.E.; Dumroese, R.K.; Landis, T.D. National Proceedings: Forest and Conservation Nursery Associations - 2006. Proceedings RMRS-P-50. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 54-60