Root and Butt Rot by Hyphodontia aspera in Red Spruce and Balsam Fir. T. C. Harrington, Department of Plant Biology, University of New Hampshire, Durham 03824. D. M. Rizzo, Department of Plant Biology, University of New Hampshire, Durham 03824. Plant Dis. 74:615. Accepted for publication 16 April 1990. Copyright 1990 The American Phytopathological Society. DOI: 10.1094/PD-74-0615D.
Hyphodontia aspera (Fr.) John Erikss. (syn. Grandinia aspera Fr.)
was isolated in pure culture from living roots of Picea rubens Sarg.
and Abies balsamea (L.) Mill. collected at high elevations in New
Hampshire. Decay (white and stringy, with small black flecks) was
found in the center (older growth rings) of the roots and butts of
affected trees. Single-spore cultures from basidiomata of H. aspera
on two dead trees were compatible with butt rot isolates in dikaryon-monokaryon
pairings. On woody substrata and in hymenia, capitate
cystidia with fragile halos formed that were similar to those of
Resinicium spp. Earlier reports (1,2) referred to this root and butt
rot fungus as Resinicium sp., but single-spore isolates were compatible
with H. aspera isolates from Europe (courtesy ofN. Hallenberg). Rarity
of basidiomata and poor growth and survival in culture may explain
why H. aspera was not identified in previous studies.