Biology Reference
In-Depth Information
large pruning wounds on older trees; the canker
seldom appears on trees less than 10 years old.
Shellac pruning cuts immediately; sterilize tools
between cuts.
Nummularia discreeta (see
Pezicula
Ascomycetes, Helotiales
Biscogniauxia
marginata
).
Blister Canker
of apple, crabapple,
pear, mountain ash; also reported on service-
berry, birch, elm, magnolia, and honey locust.
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Apothecia similar to
Dermatea
but lighter.
Pezicula carpinea
Bark Canker
of hornbeam.
Pezicula corticola
Superficial Bark Canker
and
Fruit Rot
, rather common on apple and pears.
Hyaline, one-celled conidia of the
Myxosporium
stage are formed in acervuli.
Pezicula pruinosa
Canker
on branches of
amelanchier.
Ophionectria (Scoleconectria)
Ascomycetes, Hypocreales
Perithecia red to white, globoid, with a round
ostiole, superficial, paraphyses lacking; spores
needle-shaped to filiform, light colored.
Ophionectria balsamea (see
Phacidiella
Thyronectria
balsamea
).
Bark Canker
of balsam fir.
Ophionectria
▶
Ascomycetes, Helotiales
scolecospora (see
Asci borne in hymenial layers, covered with
a membrane until mature, then splitting;
apothecia remain embedded in a stroma; paraph-
yses present; asci clavate.
Phacidiella coniferarum (Anamorph,
Phacidium coniferarum
).
Phomopsis Disease
of
conifers. The fungus is usually saprophytic, but it
is parasitic on Douglas-fir and larch in Europe
and on living pine in Maine.
Scoleconectria cucurbitula
).
Bark Canker
of
balsam and alpine firs.
Scoleconectria cucurbitula (formerly
Ophionectria scolecospora
).
Bark Canker
of bal-
sam and alpine firs.
Thyronectria balsamea (formerly
Ophionectria balsamea
).
Bark Canker
of balsam
fir.
▶
Penicillium
Phomopsis
Deuteromycetes, Hyphomycetes
Blights
.
Phacidiopycnis boycei (formerly
Phomopsis
boycei
).
Phomopsis Canker
of lowland white
fir. Branches or main stem of saplings may be
girdled and killed; there is often swelling at base
of canker where dead tissues join living.
The reddish brown needles of dead branches
are prominent against living foliage.
Phacidiopycnis piri (Teleomorph,
Potabiamyces pyri
, formerly
Phomopsis dis-
color
). Pear branch canker and fruit rot.
Phomopsis alnea
Canker
of European black
alder.
Phomopsis
▶
Conidia in heads; conidiophores unequally verti-
cillate at tip in whorls; globose conidia formed in
chains, one-celled, hyaline or brightly colored in
mass; parasitic or saprophytic.
Penicillium vermoeseni
Penicillium Disease
of
Ornamental palms, serious in southern California
with symptoms varying according to type of palm.
On queen palm (
Arecastrum
or
Cocos plumosa
)
the disease is a trunk canker, which may remain
inconspicuous for several years but leads to weak-
ening and breaking of trunk. Infected trees should
be removed at an early stage. On Canary date palm
the disease is a leafbase rot, and on Washington
abudrot.
amygdali
Branch Dieback
on
Rots
.
almond.
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