VIEW ARTICLE

Genetics

Relatedness of Strains of Fusarium oxysporum from Crucifers Measured by Examination of Mitochondrial and Ribosomal DNA. H. Corby Kistler, Plant Pathology Department, University of Florida, Gainesville 32611; Paul W. Bosland(2), Ulla Benny(3), Sally Leong(4), and Paul H. Williams(5). (2)Department of Plant Pathology, University of Wisconsin, Madison 53706, Present address: Department of Horticulture, New Mexico State University, Las Cruces 88003-3530; (3)Plant Pathology Department, University of Florida, Gainesville 32611; (4)(5)Department of Plant Pathology, University of Wisconsin, Madison 53706. Phytopathology 77:1289-1293. Accepted for publication 9 March 1987. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1987. DOI: 10.1094/Phyto-77-1289.

DNA was examined from 25 isolates representing three formae speciales of Fusarium oxysporum from crucifers. The restriction enzyme fragment patterns of mitochondrial DNA (mtDNA) and nuclear ribosomal DNA (rDNA) were compared among isolates to examine phylogenetic relationships among pathotypes and to determine whether any restriction fragment-length polymorphisms (RFLPs) were associated with geographic origin. No differences in rDNA restriction fragment patterns were seen among isolates regardless of pathotype or geographic origin. RFLPs were detected in mtDNA, and these corresponded directly with forma specialis. A unique mtDNA restriction enzyme fragment pattern was detected in one isolate from Japan, indicating that geographical divergence is present in the pathogen population. All isolates examined contained plasmid-like DNA (plDNA). Three different plDNAs were detected and were also correlated with forma specialis.