Biology Reference
In-Depth Information
Sydowia
Tympanis
Ascomycetes, Dothidiales
Ascomycetes, Helotiales, Helotiaceae
Asci usually short, cylindrical, and relatively
numerous, in spherical, ostiolate locules.
Sydowia polyspora
Twig Dieback
on fir.
Ascocarp
cup-shaped;
sclerotia
absent;
expiculum usually, if parallel hyphae.
Tympanis confusa
Canker
on pine.
Thyronectria
Valsa
Ascomycetes, Hypocreales
Ascomycetes, Diaporthales
Stroma valsoid with several perithecia, bright-
colored; spores muriform, hyaline to subhyaline.
Thyronectria austro-americana
Canker
,
Wilt
of honeylocust. Slightly depressed cankers rang-
ing from pinhead size to 1/2 inch grow together
and enlarge to girdle a branch. Underlying wood
is streaked reddish brown for several inches from
the canker, and there is often a gummy exudate.
Some trees die, but many survive.
Thyronectria balsamea
Canker
on fir.
Thyronectria berolinensis
Cane Knot Canker
of fruiting and flowering currants.
Many perithecia in a circle in a stroma in
bark; flask-shaped with long necks opening to
the surface; spores hyaline, one-celled, curved,
slender.
Leucostoma cincta (formerly
Valsa cincta
).
Perennial Canker
of peach,
Dieback
, also on
nectarine. The fungus is apparently infective dur-
ing the dormant season, entering through
wounds, dead buds, leaf scars, and fruit spurs. It
forms a canker complex with
V. leucostoma
and
sometimes the brown-rot fungus. It is more com-
mon in northern latitudes than in southern, but is
not important in well-cared-for orchards.
Leucostoma kunzei (formerly Valsa kunzei).
▶
Cytospora kunzei
.
Leucostoma persoonii (formerly
Valsa
leucostoma
).
Apple Canker
,
Dieback
,
Twig
Blight
on apple, apricot, peach, pear, quince,
plum, cherry, willow, and mountain-ash. The
fungus is a weak parasite entering through
wounds or twigs killed by frost.
Valsa cincta (see
Trichothecium
Rots
.
Trichothecium roseum
Canker
of rose.
▶
Leucostoma cincta
).
Peren-
nial Canker
of peach,
Dieback
, also on nectarine.
Valsa kunzei
▶
Tubercularia
Leucostoma
kunzei
).
(see
▶
Deuteromycetes, Hyphomycetes
Cytosporakunzei
.
Valsa cincta (see
▶
Leucostoma cincta
). Peren-
nial Canker of peach, Die back, also on nectar-
ine. Valsa kunzei (see
▶
▶
Forms bright colored cushions, mostly on wood
or bark; fine branching conidiophores bearing
small, elipsoidal hyaline conidia.
Tubercularia ulmea
Canker
on Russian olive
and honeylocust.
Leucostoma kunzei
).
Cytospora kunzei
.
Valsa
▶
Leucostoma
persoonii
).
Apple Canker
,
Dieback
,
Twig Blight
leucostoma
(see
▶
