Phoma glomerata (Corda) Wollenw. &; Hochapfel a new threat causing cankers on shoots of peach trees in Greece

Shoot blights are common diseases of peach trees in Greece. This study is the first report of a shoot blight and canker disease of peach in Greece caused by the fungus Phoma glomerata (Corda) Wollenw. & Hochapfel. The pathogen caused distinct cankers with abundant gumming on shoots of peach trees. The rate of development of P. glomerata in vitro was reduced as temperatures increased from 25°C to 30°C, decreased from 25°C to 15°C, and was totally inhibited at 35 and 10°C. The rate of conidial germination and the germ tube elongation in vitro was reduced as temperatures increased from 25°C to 35°C, decreased from 25°C to 10°C, and was totally inhibited at 2–4°C. Pathogenicity tests showed that 24 peach and nectarine cultivars grown in Imathia Perfecture, Greece, were equally susceptible to P. glomerata. The fungicides thiophanate methyl, carbendazim, and tebuconazole were evaluated against the development of P. glomerata and disease symptoms. All fungicides inhibited the growth and conidial germination of P. glomereta and disease symptoms, and all 30 isolates tested were sensitive to the above fungicides. The disease caused by P. glomerata could be a threat to peach cultivation in Greece and its management should be investigated in the field.