ANTHRACNOSE OF THE MANGO IN FLORIDA. 3 
Beneath mango trees the disease can be found on the fallen leaves 
and , as previously mentioned, the blighted peduncles frequently 
remain in situ for many weeks. These produce spores when condi- 
tions of moisture are suitable, and when a second bloom follows 
before they have fallen the conditions for infection are ideal. Even 
after they have fallen to the ground they may continue to be a source 
of infection for some weeks. The mango branch illustrated in Plate II, 
figure 1, was photographed on March 4, 1912, and shows a persistent, 
diseased peduncle of the January bloom, with the young March bloom 
appearing around it. 
It seems likely that the potential possibilities for infection are very 
great at all times and that all that is needed is a favorable season as 
regards moisture to produce the disease in abundance. 
It is probable that the spores do not retain their viability for a 
great length of time. Pedicels showing spores of the fungus were 
collected the last week in February, 1912. They were kept in an 
envelope in a laboratory drawer until July 10 of that year, when 
attempts were made to germinate them in drops of water on glass 
slides. A number of slides were prepared on several successive days, 
but no germination was obtained. Inasmuch as the fresh spores 
germinate readily under such conditions, it is to be inferred that these 
spores were no longer viable. Under tropical conditions, however, 
fresh supplies of spores are being continually produced throughout 
the year. 
INFECTION EXPERIMENTS. 
. Infection experiments were planned to determine whether the 
flower clusters of the mango could be artificially inoculated with this 
fungus and whether the results of such inoculation would be similar 
to the natural infection observed. The experiments were limited in 
size and should, perhaps, be repeated on a larger scale, but taken in 
connection with the other facts presented, i. e., the constant associa- 
tion of this fungus and this alone, as no other was found on diseased 
inflorescences, and the observations of Bessey and Rolfs given later, 
they seem to be sufficient to remove any reasonable doubt as to the 
cause of the disease in Florida. A seedling tree in the Subtropical 
Garden at Miami was selected for this work. Fourteen buds which 
had just begun to swell were covered on February 26, 1912, with 
manila paper bags, which were then tied securely around the branches. 
On March 5 the bags were removed from four buds, which were about 
2 inches long at that time. One was sprayed with distilled water 
with an atomizer, and three with distilled water containing spores of 
the anthracnose fungus. They were all immediately rebagged. The 
work was done at 10 o'clock a. m. on a calm day, and no shoot was 
exposed for more than three minutes. The spores for all the infec- 
tion experiments were obtained from diseased panicles which had 
