Search

Fusarium corm rot, caused by Fusarium oxysporum f. sp. gladioli (fogl), is the most important disease of saffron, causing severe yield losses in Italy. Sixty-two isolates of fogl collected from saffron corms in central Italy (Abruzzo and Umbria) and five isolates obtained from Spain were characterized by rep-PCR, using the primers BOX and REP. Isolates of F. oxysporum ff.sp. cyclaminis, lactucae, lycopersici, melongenae, melonis and radicis-lycopersici and isolates of F. avenaceum, F. equiseti, F. graminearum, F. proliferatum, F. sporotriochioides, F. semitectum and F. solani were included in the analyses for comparison. Primers REP discriminated fogl, from the other species or formae speciales better than BOX. Cluster analysis, performed with the Dice's coefficient, revealed a big cluster which includes 50 fogl (75%) and one F. solani isolates. Within this cluster, Spanish isolates were clearly separated in a sub-cluster. Our results confirm the suit ability of rep-PCR for Fusarium species and formae speciales characterization. The primers E-F and A-B described by de Haan et al. (2000) for the race 1 of fogl are not suitable for a real-time PCR-based assay we intend to develop for detecting fogl isolates in saffron corms and in soils. All saffron fogl isolates and other Fusarium spp. generated a DNA band with a different mass respect to that expected. RAPD analysis is in progress to find specific sequences for developing the real-time PCR-based assay. [ABSTRACT FROM AUTHOR]