Fomitopsis sp. causing brown rot in wood of living citrus trees reported for first time in southern Italy.

In the spring of 2008 a brown wood rot in 40-year-old orange trees (Citrus sinensis cv. Valencia late) was observed in an orchard in the province of Taranto , Apulia region, Southern Italy . Affected trees (about 20%), showed symptoms of leafchlorosis, twig dieback and branch breakdown. In the incipient stage of decay the wood showed a yellow-brown discoloration (Fig. 1), which progressed into a wood rot. The fungal mycelium, consistently isolated from decaying wood on potato dextrose agar (PDA), was white, slow growing, slightly raised and cottony-floccose (Fig. 2), with a distinct mushroom odour; hyphae were hyaline, thin-walled, nodose-septate and branched. Representative isolates had identical internal transcribed spacer (ITS) regions (GenBank Accession Nos. HM126455 to HM126460) and were identified as Fomitopsis sp. since their sequences showed 99-100% identity with available sequences in GenBank.