Biology Reference
In-Depth Information
delphinium, geum, golden-glow, marsh-mari-
gold, and viola. Pick off and burn affected parts.
Synchytrium endobioticum
Potato Wart
,
Black Wart
of potatoes, a warty hypertrophy of
tubers. A European disease wart was found in
1918 in backyard gardens in mining towns of
Pennsylvania, Maryland, and West Virginia. Dis-
eased tubers had apparently been brought in by
immigrants. A strict quarantine was placed on
infested districts, and there has been no spread
to commercial potato fields. The disease shows as
prominent outgrowths or warts originating in the
eyes, varying from the size of a pea to that of the
tuber itself. Numerous yellow sporangia are
released into the soil by decay of the malformed
tissue. The disease, which may affect other spe-
cies of
Solanum
, is spread by contaminated soil or
infected tubers. Buds and adventitious shoots of
tomato are infected below the soil line.
Control
By 1953 potato wart had been eradi-
cated from more than half of the 1,112 infested
gardens in Pennsylvania. The plan called for
applying copper sulfate the first year, keeping
the land clean and cultivated, applying lime the
next year, growing vegetables the third year, and
going back to potatoes the fourth year to test
results.
Synchytrium vaccinii
Red Leaf Gall
on cran-
berry, azalea, chamaedaphne, gaultheria, and
ledum, from New Jersey northward. On cran-
berry the disease appears just before blossoms
open. Buds, flowers and young leaves are covered
with small, red, somewhat globular galls about
the size of birdshot; affected shoots bear no fruit.
The disease is erratic in appearance but is most
frequent in bogs that have excessive or uneven
water supply.
Synchytrium sp
Stem Gall
on castor bean, in
Texas. Small red galls on stems, petioles, and
leaves of seedlings.
Plasmopara
Downy Mildews
.
Plasmopara halstedii
Basal Gall
on sunflower.
▶
Protomyces
Archiascomycetes, Taphrinales
Protomyces gravidus
Stem gall
on ragweed.
Protomyces macrosporus
Leaf gall
on hedge
parsley (
Torilis
sp.).
Sphaeropsis
Cankers and Diebacks
.
Sphaeropsis tumefaciens
Canker
and
Gall
on
Carissa
.
▶
Synchytrium
Chytridiomycetes, Chytridiales
Mycelium lacking; thallus converted into a soros
with amembrane, at maturity functioning in entirety
as a resting sporangium or divided to form many
sporangia in a common membrane; zoospores with
one cillum at posterior end. Various species cause
excrescences on leaves and fruit; potato wart.
Synchytrium anemones
Leaf Gall
,
Flower Spot
of anemone and thalictrum. Flowers are spotted,
distorted, dwarfed, and may fall. Red spots are
formed on leaves and stems.
Synchytrium aureum
Red Leaf Gall
,
False Rust
on many plants, 130 species in widely separated
genera, including calypha, artemisia, clintonia,
