208 MANUAL OF FRUIT DISEASES 
Cause of anthracnose. 
This is a fungous disease, the cause of which is Pseudopeziza 
Ribis. The fungus is carried through the winter by either the 
conidial or the sexual stages and possibly as mycelium in the 
canes. The infected leaves fall to the ground in the autumn, 
and the fungus then penetrates all the tissues. Later it develops 
an apothecium. In the spring ascopores ripen and are carried 
to the new leaves, probably by the wind, although no observa- 
tions have been made on this point. The time of inoculation 
is unknown, but severely infected plants have been seen on 
June 8. It is known that about two weeks are required for 
germination, penetration and the production of visible signs 
of the disease, from which it may be reasoned that inoculation 
occurs about the middle of May. The germtube within the 
leaf, or other susceptible part of the plant, develops mycelium 
which grows in localized areas and kills the tissues, resulting 
in the formation of the lesions already described. The my- 
celium finally forms a mat near the center of the spot where an 
acervulus develops. At maturity this structure ruptures the 
epidermis, liberating the conidia in gelatinous masses. These 
spores are disseminated by rain and insects, but, on account of 
their gelatinous character, probably are never carried by wind. 
The conidia continue to propagate the pathogene throughout 
the growing-season, thus accounting for the extent of the disease 
in a local area. Conidia produced in late summer are capable 
of living through the winter. Although, as previously stated, 
mycelium in the canes may possibly tide the fungus over winter, 
yet there is considerable evidence to the contrary. 
Control. 
It has been conclusively shown that bordeaux mixture 5-5- 
50, or lime-sulfur solution 1-40 or 1-50, when applied at the 
right time, is effective in the control of anthracnose. It has 
recently been found that dusting with the sulfur-lead mixture 
(90 parts finely ground sulfur to 10 parts powdered lead ar- 
