Using ISSR and URP-PCR markers in detecting genetic diversity among Macrophomina phaseolina isolates of sesame in Iran

To assess the variability of Macrophomina phaseolina (Tassi) Goid, the causal agent of charcoal rot of Sesame, sixty isolates recovered from ten geographic regions, were analyzed using inter simple sequence repeat (ISSR) and universal rice primer (URP) markers. Isolates were grouped into eight clusters at 78% genetic similarity level. Our results showed that the five ISSR primers produced 105 bands of which 77.11% were polymorphic and eight URP-PCR primers generated 135 bands of which 66.84% were polymorphic. These methods showed a considerable genetic diversity among Iranian isolates, but no correlation was found between genetic diversity and geographical origins of the isolates. Analysis of molecular variance revealed that a large proportion of genetic variability resulted from the differences among isolates within regions. The findings of this study demonstrated that the low-genetic differentiation (GST) and high gene flow (Nm) among populations had a significant effect on the emergence and evolutionary development of M. phaseolina.