Puccinia polysora rust on field corn in the Everglades of Florida


Robert, A.L.; Wiser, W.J.

Plant Dis Reporter 41(10): 856

1957


In May 1957, rust on field corn caused by Puccinia polysora was found for the 1st time in the Everglades area of Florida. Specimens in the National Fungus Collections show that, in Florida, this rust was first collected in 1901 on Tripsacum dactyloides on Hog Island. In 1923, it was found in Seminole County near St. John's River, Sanford, on Erianthus divaricatus, and in the same area in 1924 on corn. In 1943, specimens were collected from late plantings of field corn near Quincy in Gadsden County and near Jay in Santa Rosa County. It was reported to be rather severe and widespread on these 1943 late corn plantings.

856
Vol.
41,
No.
10
--PLANT
DISEASE
REPORTER
--Oct.
15,
1957
PUCCINIA
POLYSORA
RUST
ON
FIELD
CORN
IN
THE
EVERGLADES
OF
FLORIDA
1
Alice
L.
Robert
and
W.
J.
Wiser
2
In
May
1957,
rust
on
field
corn
caused
by
Puccinia
polysora
was
found
for
the
first
time
in
the
Everglades
area
of
Florida.
The
infection
was
observed
in
cooperative
field
corn
plantings
of
the
United
States
Department
of
Agriculture
and
the
Everglades
Experiment
Station
at
Belle
Glade,
Florida.
The
first
uredia
of
this
rust
were
noted
on
May
14
when
small
groups
of
yel-
low
pustules
appeared
sparingly
on
the
upper
surface
of
the
leaves
of
some
plants.
By
May
20
a
moderate
to
heavy
infection
was
apparent
on
some
strains
of
corn.
This
development
indi-
cated
that
spore
showers
were
deposited
on
the
leaves
around
May
9
to
12.
Spread
of
this
rust
after
May
21
was
moderate.
Specimens
in
the
National
Fungus
Collections
show
that,
in
Florida,
this
rust
was
first
collected
in
1901
on
Tripsacum
dactyloides
on
Hog
Island.
In
1923,
it
was
found
in
Seminole
County
near
St.
John's
River,
Sanford,
on
Erianthus
divaricatus,
and
In
the
same
area
in
1924
on
corn.
In
1943,
specimens
were
collected
from
late
plantings
of
field
corn
near
Quincy
in
Gadsden
County
and
near
Jay
in
Santa
Rosa
County.
It
was
reported
to
be
rather
severe
and
widespread
on
these
1943
late
corn
plantings.
It
has
been
generally
noted
by
workers
and
observers
in
Africa
and
the
United
States
that
infection
and
severity
of
attack
by
Puccinia
polysora
may
be
closely
correlated
with
higher
temperatures
and
rainfall.
3
Above
normal
rainfall
and
high
temperatures
during
April
and
May
in
the
Belle
Glade
area
of
Florida
produced
favorable
conditions
for
the
development
of
this
rust
in
1957.
It
may
be
present
at
all
times
as
a
potential
disease
-producing
fungus.
Rust
caused
by
Puccinia
sorghi
was
present
in
a
light
infection
at
the
Everglades
Experi-
ment
Station
in
1957.
Almost
all
of
the
uredia
were
parasitized
by
Darluca
filum,
with
the
urediospores
becoming
displaced
by
pycnidia
of
this
rust
parasite.
Most
of
the
remaining
urediospores
were
pale
yellow
and
vacuolated.
By
May
21
some
of
the
uredia
of
P.
polysora
also
were
parasitized
by
D.
filum
and,
as
the
season
advanced,
more
became
parasitized.
UNITED
STATES
DEPARTMENT
OF
AGRICULTURE,
AGRICULTURAL
RESEARCH
SERVICE,
FLORIDA
AGRICULTURAL
EXPERIMENT
STATIONS
1
2
3
Crops
Research
Division,
Agricultural
Research
Service,
United
States
Department
of
Agricul-
ture,
cooperating
with
the
Florida
Agricultural
Experiment
Stations.
Pathologist
and
Agronomist,
Crops
Research
Division,
Agricultural
Research
Service,
United
States
Department
of
Agriculture.
Wood,
Jessie
I.
,
and
Bernard
R.
Lipscomb.
Spread
of
Puccinia
polysora
with
a
bibliography
on
the
three
rusts
of
Zea
mays.
Special
Publication
No.
9,
Plant
Disease
Epidemics
and
Identifica-
tion
Section,
ARS,
USDA,
April
15,
1956.
gie