Biology Reference
In-Depth Information
Puccinia malvacearum
Hollyhock Rust
. III
general on hollyhock, also on mallow, and
lavatera. This rust is so common and destructive
it limits the use of hollyhocks as ornamentals.
Stems, leaves, bracts may be attacked. There are
yellow areas on the upper surface of leaves,
orange-red spore pustules on the underside, and
elongated lesions on stems. Spore pustules are
sometimes grayish from formation of sporidia,
but the alternate host is unknown. In severe infec-
tions leaves dry and hang down along the stem.
The fungus winters in pustules in basal leaves and
in old stems.
Control
Cleaning up all infected plant parts in
fall and again very early in spring is most impor-
tant; infection starts early in the season, and once
it is under way, it is very difficult to curb with
a fungicide.
Puccinia melampodii (formerly
poae-nemoralis
).
Bluegrass Leaf Rust
,
Yellow
Leaf Rust
. II, III on turf grasses, mostly Canada
and Kentucky bluegrass; 0, I, unknown; general
east of the Rocky Mountains.
Puccinia polygoni-amphibii Rust; II, III, on
jointweed.
Puccinia polysora
Southern Corn Rust
.0,I,
unknown; II, III on corn and grasses. Present in
the South, requiring higher temperatures than
common corn rust; not very important. Uredio-
spores are yellow to golden, teliospores chestnut
brown, angular; often parasitized by
Darluca
filum.
Puccinia psidii
Rust
on allspice (
Pimenta
dioica
)
Melaleuca quinquenervia
, and
Syzygium
jambos
.
Puccinia pygmaea
Rust
on grasses.
Puccinia recondita (
P. rubigo-vera
).
Leaf Rust
of cereals and grasses, with several varieties:
P. recondita tritici (
P. triticina
). II, III on wheat
(but not grasses); 0, I on meadow rue. This rust is
worldwide and more serious than stem rust in the
southern half of the American wheat belt, some-
times epiphytotic with losses up to 30 %. The leaf
tissue is progressively destroyed through the sea-
son, resulting in a reduced number of kernels,
shriveled grain, low weight and protein content.
Rust pustules breaking through the epidermis
greatly increase transpiration losses. Orange
uredial pustules are followed later by gray telial
sori, but urediospores are the effective spore form
and can survive southern winters. There are many
physiological races.
P. recondita agropyri
. II, III on wheat grasses
and wild ryegrasses; 0, I on clematis, buttercup,
columbine, larkspur, and other Ranuculaceae.
Common in Rocky Mountain area.
P. recondita agropyrina
. Similar to the above
but occurring outside mountainous areas.
P. recondita apocrypta
. II, III on wheat and
wild grasses; 0, I on waterleaf and mertensia.
P. recondita impatientis
. II, III on redtop and
related grasses; 0, I on touch-me-not.
P. recondita secalis
. II, III on rye; 0, I on
bugloss (
Lycopsis
).
Puccinia solheimi On dodocatheon, Wyoming.
Puccinia sorghi
Corn Rust
. 0, I on oxalis; II, III
on corn, sweetcorn, general in northeastern and
Puccinia
flaveriae
). On
Calendula
.
Puccinia melampodii On
Baccharis
, Texas.
Puccinia menthae
Spearmint Rust
. 0, I, II, III
on spearmint, peppermint, oregano, also horse-
mint, mountain-mint, dittany, bee-balm, yerba
buena, and germander; especially serious for
mint farmers in Middle West and Northwest. In
spring and early summer the disease appears as
light yellow to brown raised spots on deformed
stems and leafstalks, sometimes on main veins;
golden to chocolate brown spots appear in late
summer and fall. Affected leaves dry, and the
yield of oil is reduced. The pathogen has at least
10 races. Dusting with sulfur and early cutting are
recommended.
Puccinia nakanishikii
Rust
on lemon grass.
Puccinia pelargonii-zonalis
Pelargonium
Rust
. The uredinial stage of a rust, presumably
this species, was found on geranium in New York
and California in 1967. It has now been reported
in Pennsylvania and Florida. Brown spore pus-
tules appear on leaves, petioles, and stems; leaves
turn yellow and drop. Destroy infected plants.
Puccinia phragmitis 0, I on rhubarb; II, III on
reed grass, sometimes present in California but
not serious. Aecia are white, on underside of
rhubarb leaves, surrounded by pycnia.
Puccinia poae-nemoralis
(Syn. P. poae-
sudeticae) (see
Puccinia brachypodii
var.
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