Biology Reference
In-Depth Information
Rots
A rot is a decay, a decomposition or disintegra-
tion of plant tissue. It may be a hard dry decay or
a soft and squashy one. It may affect root or
rhizome, stem, tree trunk, blossom or fruit.
Some rots also affect leaves, but diseases that
are primarily of foliage are more often designated
leaf spots or blights. Rots caused by bacteria are
discussed under Bacterial Diseases.
There are a great many wood rots of trees,
recognized by the sporophores or conks of the
various species of
Fomes, Polyporus
, and other
shelving or bracket fungi. By the time these signs
appear, it is usually too late to do anything about
the disease. The tree-rot fungi enter through unpro-
tected wounds - either pruning cuts or breaks due
to wind and icestorms. For proper pruning
methods and treatment of wounds, see U. S.
Department of Agriculture Farmers' Bulletin
1896,
Care of Damaged Shade Trees, Tree Main-
tenance
by P. P. Pirone or
Tree Experts Manual
by
Richard R. Fenska. The fact that tree wound dress-
ings are now available in convenient aerosol
bombs should make it easier for home gardeners
to protect pruning cuts from wood-rotting fungi.
rot thriving in warmer sections, more important
in New Jersey than in Massachusetts.
Physalospora vaccini (formerly
Acanthorhynchus vaccinii
).
Cranberry Blotch
Rot
, a common fruit rot thriving in warmer sec-
tions, more important in New Jersey than in Mas-
sachusetts. The rot starts as a small, light-colored
spot on the berry, spreading to destroy the whole
fruit, with dark blotches on the skin. The fungus
may invade leaves, but it seldom fruits on them
until they have fallen. Cranberry bogs in New
Jersey may need three or four sprays of Bordeaux
mixtures starting at midbloom, but in Massachu-
setts two are sufficient.
Acremonium
Acremonium sp.
Root Rot
on melon and
watermelon.
Alternaria
Blights
.
Alternaria alternata
Fruit Rot
on tomato and
black pit disease on potato tubers (stored).
Alternaria citri
Alternaria Rot
of citrus fruits,
navel-end rot, black rot, widespread, prevalent in
warm dry sections, but not too serious. In oranges
the rot is most common in the Washington Navel
variety - a firm, dry, black rot at the navel end,
often in only one segment, with fruit coloring
prematurely, appearing sound on the outside.
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Physalospora (Acanthorhynchus)
Ascomycetes, Amphisphaeriales
Perithecia separate, innate, beaked; spores one-
celled, dark.
Acanthorhynchus vaccinii (see
Physalospora
vaccini
).
Cranberry Blotch Rot
, a common fruit
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