Pathogenicity and genetic variation of Iranian isolates of Fusarium oxysporum from sugar beet in Iran.

摘要: Pathogenicity and genetic variability of 13 isolates of Fusarium oxysporumfrom sugar beet were evaluated. Samples were collected from six provinces of Iran during 1999-2008. Pathogenic variability of the isolates was determined using a root-dip assay in spore suspension for 4-week-old plants. The isolates were classified into strong and weak pathogenic groups. DNA was extracted from F. oxysporum isolates and their molecular variability was investigated by 15 random amplified polymorphic DNA (RAPD) analysis of the PCR-amplified internal transcribed spacer (ITS) regions of ribosomal DNA. Digestion of the PCR products with the restriction enzymes EcoR1, Taq1 and HaeIII produced fragments of similar sizes. Cluster analysis using the unweighted pair-group method with arithmetic mean (UPGMA) clearly separated the isolates into five groups. A relationship was found between RAPD results and geographical origins of the isolates. However, no relationship was found between RAPD results and pathogenicity.