Pyrofomes demidoffii newly reported to cause a white trunk rot of juniper (Juniperus formosana) in China

Juniperus formosana has a wide distribution in China, and it is an important conifer tree in central and southwestern China. In the summer of 2006, a typical white trunk rot of the treewas observed at Wolong area (30°50'N, 103°10'E), DujiangyanCounty, central SichuanProvince, Southwest China. Twelve trees were affected from 85 examined, and showed signs of advanced internal decay of the trunk.

A perennial, ungulate and woody polypore was found on the trunk of affected trees. Fruiting bodies were 12-15 cm wide and 14 cm thick at the base. The upper surface was greyish black, the poroid surface bright yellow to orange brown with densely packed tubes (around 3-4 per mm). The inside of the fruiting bodies was cinnamon to brick-red and contained dimitic hyphae; the generative hyphae had clamp connections. Basidiospores were ellipsoid, truncate, thick-walled, pale brownish, slightly dextrinoid and cyanophilous, 6-8x5-6 µm. These characteristics agree with the published description of Pyrofomes demidoffii (Ryvarden & Gilbertson, 1994) and match specimens examined from the Herbarium of the BotanicalMuseum of the University of Helsinki (H). Voucher specimens have been deposited at the Institute of Applied Ecology, ChineseAcademy of Sciences (IFP).

Previously P. demidoffii has been recorded on junipers in Central Europe, Africa and North America(Ryvarden & Gilbertson, 1994). It grows exclusively on Juniperus spp. and causes a white trunk rot of living trees. The fungus causes major decay of junipers in western North America (Scharpf, 1993) and Pakistan (Zakaullah, 1978). P. demidoffii was not found in previous surveys (Dai et al., 2007) and this is to our knowledge the first report of P. demidoffii on Juniperus formosana from China.