Differentiation of Stemphylium solani isolates using random amplified polymorphic DNA markers

Stemphylium solani isolates infect two varieties of eggplant, Solanum aethiopicum and Solanum melongena grown in Senegal (West Africa) and are morphologically quite similar. Using the random amplified polymorphic DNA (RAPD) procedure with arbitrary 10-mer primers, we were able to differentiate these S. solani isolates into two groups directly related to their plant host origin. A RAPD product of approximately 480 bases pairs obtained with OPF-20 primer were polymorphic between the two groups. Four new primers (F20F1, F20F2, F20R1 and F20R2) based on nucleotide sequence analysis of this 480 bases pairs RAPD fragment were developed. Such primers used pairwise amplified a single fragment from the DNA of S. solani isolates whatever their host origin. However, DNA extracted from Fusarium oxysporum (f. sp. vasinfectum, f. sp. elaeidis), Verticillium dahliae and Phyllosticta sp. isolates did not amplify using these primers. Our results indicate that these primers sets were good tools for specific identification of these two eggplants S. solani isolates by polymerase chain reaction (PCR).