First report of Hakea sericea leaf infection caused by Pestalotiopsis funerea in Portugal.
In May 2003, unusual leaf spots were observed on naturally growing Hakea sericea plants in Portugal. Infected plants exhibited reddish leaves bearing black, 1- to 3-mm circular lesions. Leaf sections containing necrotic lesions were plated onto potato dextrose agar and eight fungal isolates were obtained. Pure cultures exhibited pinkish mycelium, bearing compact acervuli that contained black slimy spore masses. Microscopic observation revealed typical Pestalotiopsis sp. five-celled spores with three to four apical and one basal appendage. Molecular techniques were performed. ITS sequences from all fungal isolates were identical to each other and only four base pairs were different (99.3% similarity) from Pestalotiopsis funerea. Pathogenicity tests were performed and after 6 days, only leaf-wounded plants infected by P. funerea exhibited lesions identical to those observed in field plants, and bearing fungal spores identical to those from original isolates.