Biology Reference
In-Depth Information
reported from Florida. Numerous spots on leaves
and stems are scattered or grouped and nearly
confluent; centers are depressed, buff-colored,
with purple margins.
Sphaceloma menthae
Mint Anthracnose
,
Leopard Spot Disease
. Circular, oval or irregular
spots on leaves, stems, and rootstocks are black
with white centers, up to 5 mm. Formerly serious,
this disease is now controlled in commercial mint
fields by fall plowing, covering plants deeply.
Sphaceloma morindae
Morinda Scab
. Buff-
colored spots on leaves, stems, and petioles,
Florida.
Sphaceloma murrayi
Gray Scab
of willow.
Leaf spots are round, irregular, somewhat raised,
grayish white with narrow, dark brown margins,
often confluent, sometimes fragmenting;
Sphaceloma psidii
Guava Scab
, reported in fei-
joa in Florida.
Sphaceloma punicae
Pomegranate Spot
Anthracnose
. Very small purple spots with
paler centers on both leaf surfaces.
Sphaceloma ribis
Gooseberry Scab
, Washing-
ton. Leaf spots numerous, very small, raised, and
grayish.
Sphaceloma spondiadis
Mombin Scab
.On
purple mombin (
Spondias
) Florida.
Sphaceloma symphoricarpi
Snowberry
Anthracnose
, widespread on snowberry,
impairing beauty of ornamental plants, first
described from New York in 1910; also on coral-
berry. Leaf spots appear in early spring, minute,
dark purple to black, aging with dirty gray cen-
ters, coalescing into large areas subject to crack-
ing. Leaves may be misshapen from early
marginal infections. Spotting is inconspicuous
in flowers but pronounced on berries, with purple
areas becoming sunken and pinkish. Secondary
infection by an
Alternaria
shrivels fruit into
brown mummies. A dormant lime-sulfur spray
followed by foliage sprays may help.
Sphaceloma
long
narrow patches along veins.
Sphaceloma oleandri
Oleander Scab
. Leaf
spots spherical to irregular, densely grouped
over entire surface, whitish with brownish black
margin, slightly elevated, 1 to 4 mm.
Sphaceloma perseae
Avocado Scab
, one of the
most important avocado diseases in Florida,
some years with nearly 100 % infection; also
occurring in Texas. Leaf lesions are mostly on
upper surface, very small red spots with a dark
olive conidial growth. Fruit lesions are corky,
raised, brownish, oval, but often coalescing giv-
ing a russeted appearance; sometimes cracking to
allow entrance of fruit-rotting fungi. Avoid
highly susceptible varieties like Lulu. Spray
with bordeaux mixture as for blotch.
Sphaceloma poinsettiae
Poinsettia Scab
.
Light raised lesions on stems, veins, and midribs,
pale buff at center with purple to nearly black
margins.
viburni
Snowball
Spot
Anthracnose
.
Sphaceloma violae
Violet Scab
,
Pansy Scab
,
widespread on violet and pansy from Connecticut
to Louisiana and Texas, a limiting factor in
maintaining violet collections. Reddish spots
with white centers change to irregular to elon-
gated raised scabs on leaves and stems, often with
much distortion. Remove and burn old leaves.
Sphaceloma spp Undetermined species have
been reported on
Bignonia
, catalpa, camellia,
and sambucus, in Louisiana, on buttonwood in
Florida, rhododendron in Washington.
