Relatedness of Strains ofFusarium oxysporumfrom Crucifers Measured by Examination of Mitochondrial and Ribosomal DNA

Publisher Website
Google Scholar
Abstract
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.