Submitted to: Phytopathology
Publication Type: Abstract only
Publication Acceptance Date: 4/30/2003
Publication Date: 6/1/2003
Citation: HANSON, L.E., HILL, A.L., PANELLA, L.W. VARIABILITY IN FUSARIUM ISOLATES AFFECTING SUGAR BEET OR SPINACH. PHYTOPATHOLOGY. 2003. Interpretive Summary:
Technical Abstract: Variability in Fusarium isolates affecting sugar beet or spinach. L. E. HANSON, A.L. Hill, and L. Panella. USDA-ARS, NPA, SBRU, Fort Collins, CO Fusarium oxysporum causes wilt or yellows on a large number of crops. On sugar beet, Fusarium yellows reduces root yield as well as sucrose percentage and purity in the root. The primary causal agent is F. oxysporum f. sp. betae (FOB), although F. acuminatum also can cause the disease. We examined the species of Fusarium isolated from sugar beet with yellows symptoms that could cause symptoms on beet. Fusarium oxysporum strains isolated from sugar beet or spinach were further investigated for variability in their virulence on sugar beet in greenhouse tests and their variability in RAPD banding patterns. From a total of 103 isolates, 30 were pathogenic on sugar beets. Of these, 23 were identified as FOB. Based on RAPD patterns, the majority of the FOB strains clustered together, however, other FOB strains showed divergent patterns, and some non-pathogenic strains clustered with the FOB strains. Isolates of at least four additional Fusarium species that caused yellows symptoms were obtained. The ability of different species of Fusarium to cause yellows symptoms, as well as the variability within FOB have serious implications for disease control.