New report of Phoma glomerata on Coriandrum sativum L.

In 2011, coriander plants (Coriandrum sativum L.), showing symptoms of greyish to hell brown lesions with dark brown border between discoloured and asymptomatic tissues, were observed in Bulgaria. Pycnidia with small unicellular conidia appeared in the pale centre of the lesions. In this work, the identification of the causal agent of this disease was made applying Koch's postulates. Moreover, for a rapid and unambiguous identification of the fungal species, the internal transcribed spacers and the 5.8 rDNA gene (ITS1-5.8-ITS2) were amplified by PCR from DNA extracted from the isolated colonies. The amplicon was sequenced and analyzed using BLASTn, and showed a homology of 100% with a corresponding sequence of Phoma glomerata (accession number DQ093699). The fungus isolated, after the morphological and molecular characterization, was ascribed to the species Phoma glomerata (Corda) Wollenweber and Hochapfel. This is the first report of P. glomerata as agent of stem rot of coriander in Bulgaria and elsewhere.