Biology Reference
In-Depth Information
Phloeospora aceris
Leaf Spot
of maple, includ-
ing vine and dwarf maples. The spot is small,
rather angular, common but not important.
Asterostomella saccardoi (formerly
Phyllosticta saccardoi
).
Rhododendron Leaf
Spot
, similar to that caused by
P. maxima
.
Discochora philoprina (formerly
Phyllosticta
ilicis
(Teleomorph,
Physalospora ilicis
)).
Holly
Leaf Spot
on American and English holly and on
winterberry.
Phoma exigua (formerly
Phyllosticta
althaeina
).
Leaf Spot
,
Stem Canker
on abutilon
and hollyhock. Ashy spots have black dots of
pycnidia. The tissue sometimes becomes brittle
and falls away, leaving jagged holes.
Phoma exigua (formerly
Phyllosticta decidua
).
Leaf Spot
of agrimony, aralia, basil weed,
betony, cynoglossum, eupatorium, germander,
hierachia, hoarhound, motherwort,
Phoma
▶
Blackleg
.
Phoma sp.
Leaf Spot
on ragweed.
Phomopsis
Blights
.
Phomopsis viticola
Leaf Spot
on grape.
▶
lycopus,
Phlyctema
mint, and monarda.
Phyllosticta althaeina (see
Phoma exigua
).
Leaf Spot
,
Stem Canker
on abutilon and
hollyhock.
Phyllosticta andropogonivora
Leaf Spot
on
bluestem (Andropogon).
Phyllosticta antirrhini
Snapdragon Leaf Spot
,
Stem Rot
,
Blight
. Large circular, dark brown or
black spots, with concentric ridges, are located
most often near tips and margins of leaves; cen-
ters may be cream to pale brown, dotted with dark
pycnidia. Young leaves may be curled, older
leaves shrivel and hang down along the stem.
Petioles are girdled with brown elongated
lesions. Stems have firm brown rot with shoots
or branches wilting or have ashy white spots with
dark brown or purplish margins and stems crack-
ing in area of spots. Young seedlings may damp
off. Spray with bordeaux mixture; keep green-
house cool; avoid wetting foliage in watering;
clean up diseased plants.
Phyllosticta aucubae
Aucuba Leaf Spot
.
Brown or black zonate spots are mostly along
margins of leaves, sometimes with much defoli-
ation. Spores are exuded from leaves in yellow
tendrils, then spread by rain, or syringing in the
greenhouse.
Phyllosticta camelliae (syn. P. camelliaecola)
Camellia Leaf Spot
. Lesions are irregular brown
spots.
Phyllosticta catalpae
Catalpa Leaf Spot
. Dark
brown or black spots 1/8 to 1/4 inch in diameter,
▶
Deuteromycetes, Coelomycetes
Pycnidia dark, separate or sometimes confluent,
in or under epidermis or bark; closed or ostiolate;
conidiophores simple or forked; conidia hyaline,
one-celled, cylindrical or long spindle-shaped,
mostly bent, sickle-shaped; saprophytic usually.
Phlyctema ficuum
Leaf Spot
on strangler fig.
Phyllachora
Ascomycetes, Phyllachorales
Asci in locules, immersed in groups in a dark
stroma covered by host tissue at maturity; spores
one-celled, hyaline; paraphyses present; asci
cylindrical with short pedicels.
Phyllachora graminis
Tar Spot
,
Black Leaf
Spot
, general on wheatgrass, ryegrass, fescues,
redtop, and bent grass. Elongated grayish violet
to dark olive green spots, on both leaf surfaces,
turn glossy black. The disease is seldom serious.
Phyllachora sylvatica
Tar Spot
on fescues in
Northwest.
Phyllosticta
Blights
.
▶