PESTS AND DISEASES OF FORESTRY IN NEW ZEALAND
Phaeoacremonium rubrigenum
From Forest Health News 205, May 2010
NEW FUNGI
The February 2010 issue of the Biosecurity magazine (No. 96) listed two fungi as new to New Zealand – Phaeoacremonium rubrigenum and Heptameria obesa. Both were found during the course of high risk surveillance surveys.
Phaeoacremonium rubrigenum was isolated from branches of Melia azedarach with dieback symptoms in Napier. Other fungi, including a species of Botryosphaeria were also obtained from the live/dead margins. Whether P. rubrigenum is contributing to the dieback is unknown. Phaeoacremonium is a recently described genus associated with decline diseases of several woody hosts and with human infections (usually immuno-compromised).
In the Northern Hemisphere Phaeoacremonium rubrigenum has been isolated from bark beetles and their galleries in Quercus and Fraxinus and has also been associated with Esca disease of grapevines and with a disease of kiwifruit vines. The fungus has subsequently been found on the same host in Palmerston North.
Heptameria obesa was isolated from dead twigs and small branches of Pittosporum tenuifolium from Kawatira Junction in Nelson. Heptameria obesa has been recorded from Europe and North America on dead stems and twigs of shrubby species of Baccharis, Centaurea, Cirsium, Helichrysum, Inula, Antirrhinum and Scabiosa. It is considered to be saprophytic.
Margaret Dick
