Bulletin 208, Cucumber Diseases in Florida


fungicides properly applied will check the disease and give a
commercial control but will not, without some burdensome ex-
pense, absolutely control the disease. (Fig. 10.) Four-four-fifty
(4-4-50) Bordeaux mixture, or 4-6-50 if hydrated lime is used,
applied to both surfaces of the leaf once a week will give good
control under average weather conditions. Copper-lime dust is
also very good in controlling this disease but costs considerably
more and gives less satisfactory results than liquid Bordeaux.
 Always apply the dust early in the morning before there is
much wind and before the dew has disappeared. Make certain
that the plants are well covered. Vines covering the ground
require about 30 pounds per acre per application.

 ANGULAR LEAF SPOT AND FRUIT ROT
 The diseases of cucumbers known as angular leaf spot and
fruit rot are caused by the same bacterial organism, Bacterium
lachrymans E. F. S. & Bryan. They have been found on the
cucumbers almost every season and, although not always of
serious economic importance, cause considerable damage. These
diseases have been known to the Florida trucker for the past 15
years and are quite generally distributed over the state. They
have been reported also from most of the states north of the Ohio
River but probably are not as severe in these states as in Florida.












Fig. 11. Pile of cull cucumbers discarded because of infections of the angular
 leaf spot organism.

 In Florida the greatest damage has been reported from sections
in the north central counties. Accurate surveys conducted in
these areas showed as much as 50 percent diseased fruits in
certain fields in 1924, 1925-26and 1928 which were unmarketable.
(Fig. 11.) The disease was not severe during 1927 or 1929. This