Biology Reference
In-Depth Information
Fig. 4
Black Rot of
Grapes
overwintered mummied berries. Primary infec-
tion in spring comes from either spore form.
Thecaphora deformans
Seed Smut
of lupine.
Control
If mildew is also a problem, use a fixed
copper. Cultivate in early spring so as to cover old
mummies with soil and so eliminate that source
of inoculum.
Guignardia
turning them reddish or violet. The disease is
confined to underground parts unless continu-
ously wet weather allows the reddish-purple
mycelium to grow up the stem. Small, darker
sclerotia are embedded in this purplish mat,
which turns brown with age.
Helminthosporium
Botryosphaeria
vaccinii
).
Cranberry Early Rot
,
Scald
,
Blast
, gen-
eral on cranberry and sometimes on huckleberry.
vaccinii (see
▶
▶
Blights
.
Bipolaris cactivora (formerly
Helminthosporium cactivorum
).
Stem Rot
of
cacti,
Basal
or
Top Rot
of seedling cacti, which
turn into a shrunken brown mummy covered with
spores. Initial symptoms are yellow lesions; rot-
ting may be complete in 2 to 4 days.
Exserohilum turcicum (formerly
Helminthosporium turcicum
).
Crown Rot
of
sweet corn,
Leaf Blight
.
Helicobasidium
Basidiomycetes, Septobasidiales
An exposed cottony hymenium or fruiting layer;
basidia transversely septate; spores coiled like
a watch spring.
Helicobasidium corticioides
Brown Pocket
Rot
on subalpine fir, in Colorado.
Helicobasidium brebissonii (Anamorph,
Rhi-
zoctonia crocorum
).
Violet Root Rot
of potato,
sweet potato, asparagus, beet, carrot and some
ornamentals - ash, catalpa, chinaberry, crocus,
elm, mulberry, parthenocissus and western soap-
berry. The fungus invades roots from the soil,
▶
Blights
.
Helminthosporium
cactivorum (see
Bipolaris cactivora
).
Stem Rot
of cacti,
Basal
or
Top Rot
of seedling cacti.
Helminthosporium sesami
Stem Rot
on ses-
ame in Texas.
Helminthosporium
▶
turcicum (see
Exserohilum turcicum
).
Crown Rot
of sweet
corn,
Leaf Blight
.
▶
