Biology Reference
In-Depth Information
grows over and blackens cut surfaces of stock and
scion, preventing union and resulting in death of
scions. When outdoor roses are budded on
Manetti understock, the bud often turns black
and dies. Infection is only through wounds.
Rosa odorata
and
R. chinensis
var.
Manetti
are
both very susceptible understocks;
R. multifiora
is moderately susceptible; Ragged Robin is
immune.
Control
Use healthy understock. Spray green-
house benches, tools, etc., with copper sulfate;
prevent spread of spores by workmen on hands,
clothing, and budding knife.
Chalaropsis thielavioides (formerly
Chalara
thielavioides
).
Black Mold
of rose grafts.
Control
Resistant varieties such as Globelle, Bay
State, and Vetomold have been developed, but
the fungus has mutated to more virulent forms.
Regulating ventilators in greenhouses to reduce
humidity seems to be the most practical control,
sometimes providing heat on cool nights, even in
summer.
Melanospora (Erostrotheca)
Ascomycetes, Melanosporales
Perithecia bright, more or less soft, without beak,
paraphyses lacking; spores ellipsoid, yellow to
olivaceous. Conidial stage has many spore forms.
Erostrotheca multiformis (see
Melanospora
multiformis
(Anamorph,
Cladosporium album
)).
White Mold
of sweet pea,
White Blight
, also on
perennial pea, observed on greenhouse crops.
Melanospora multiformis (formerly
Erostrotheca multiformis
(Anamorph,
Cladosporium album
)).
White Mold
of sweet
pea,
White Blight
, also on perennial pea,
observed on greenhouse crops. Leaflets are cov-
ered with tan or buff, circular to irregular, small
to large spots with cinnamon brown pustules giv-
ing a granular appearance. White tufts of mold
represent the
Cladosporium
stage.
Pseudosclerotia are also formed in the leaves,
which may die and drop. The fungus enters
through stomata under conditions of high humid-
ity. Dusting with sulfur has been suggested.
Cladosporium
Blotch Diseases.
Cladosporium fulvum (see
Fulvia fulva
).
Leaf Mold
of tomatoes, general on greenhouse
crops, occasionally serious in gardens in wet sea-
sons in the Southeast and sometimes present in
other states.
Cladosporium herbarum
Leaf Mold
,
Pod
and Seed Spot
. The fungus is a weak parasite
causing black mold of peanut, pod spot and seed
mold of lima and kidney beans, glume spot of
bluegrass, leaf mold of pepper and tomato, some-
times a fruit mold.
Cladosporium macrocarpum
Black Mold
of
spinach, on old leaves or secondary after other
leaf spots.
Fulvia fulva (formerly
Cladosporium
fulvum
).
Leaf Mold
of tomatoes, general on
greenhouse crops, occasionally serious in gar-
dens in wet seasons in the Southeast and some-
times present in other states. Diffuse, whitish
spots on upper surface of older leaves enlarge,
turn yellow; the undersurface of the patches has
a velvety olive brown coating of spores that are
spread by air currents and in watering. Spores
remain viable about the greenhouse for several
months after plants are removed, and are some-
times carried on seed. Infection occurs only when
humidity is high.
Torula
Deuteromycetes, Hyphomycetes
Conidiophores lacking; entire branches of myce-
lium develop into simple or branched chains of
dark
conidia,
which
separate
readily;
saprophytic.
Periconia maculans
(formerly
Torula
maculans
).
Leaf Mold
on yucca.
Torula maculans (see
Periconia maculans
).
Leaf Mold
on yucca.
