Aug. xz, x&*3 
Phytophthora Faberi on Coconut and Cacao 
269 
ments have been made with both the stab method of inoculation and 
inoculation of uninjured trees. In practically every instance disease was 
produced. Out of 17 seedlings inoculated by the stab method, 16 were 
severely infected (PI. 5). Of 7 trees inoculated by merely pouring a 
zoospore suspension of the fungus into the bud, 6 contracted the dis¬ 
ease and were killed. All controls remained healthy, and reisolations of 
the fungus were readily made from the infected trees. 
One special case of inoculation of a healthy, vigorous tree under control 
conditions in the field bears further mention. The three trees used for 
this test were situated on the Faculty Hill of the College of Agriculture 
at Los Banos, Laguna Province, P. I. The trees, located near the writer's 
home, were far removed from other coconuts and were extremely healthy, 
being free from serious fungus attacks and insect infestation. They grew 
on a hillside where there was a good air movement and, consequently, a 
location not peculiarly adapted for the best development of the disease. 
The trees were approximately 3 years old at the time of inoculation. 
Cultures 1 month and 11 days old growing on corn meal were used for 
the inoculations. On November 20, 1919, rain water was poured into 
one culture flask and then as soon as zoospores were produced, the zoo¬ 
spore suspension was poured between the young folded leaves of the 
bud. Another tree was similarly inoculated, except that distilled water 
was used in place of the rain water. For a control the third tree was 
used. An equal amount of rain water free from the organism was poured 
into the bud. On December 19, 1919, the tree inoculated with the rain 
water suspension showed evidences of disease. The newly unfolded leaves 
had a series of brown spots on the leaflets forming a concentric ring 
across the entire leaf. The bud from all outward appearances was en¬ 
tirely healthy. This spotting continued to be produced on the newly 
developed leaves, becoming gradually more pronounced. On April 
10, 1920, the spotting was severe. August 6, 1920, the bud apparently 
was still healthy, but the newly unfolded leaves were badly spotted. A 
severe leaf blight was observed on October 19, 1920, and the tree showed 
evidence of being stunted. The bud appeared to be somewhat weakened. 
On January 8, 1921, the bud was almost dead, being browned, and on 
January 25, 1921, it was dead. The other two trees were healthy and 
showed a marked increase in growth over the diseased tree (PI. 4, B). 
A typical case of budrot was produced in the infected tree (PI. 3, A). 
Under field conditions in localities where epidemics of the disease are 
severe, the trees succumb faster, usually within two or three months 
from the time of infection. The inoculated tree was finally cut down 
and a longitudinal section through the bud and growing point showed 
the disease to be typical of the naturally infected cases of budrot (PI. 4, 
A). The control, as well as the tree inoculated with a zoospore suspen¬ 
sion in distilled water, remained healthy. 
Besides the coconut palm ( Cocos nucifera ), other members of the 
Palmae were also successfully inoculated with the organism, and disease 
was produced in a severe or medium form. The stab method of inocula¬ 
tion was used. A stab with a sterilized scalpel was made through or 
near the growing point and then the fungus was inserted. In each case 
the fungus was recovered from the diseased trees. The controls all 
remained healthy. 
The following seedlings were killed by the fungus attack: Archonto- 
phenix alixandraeae, Dypsis madagascarisnsis , Livistona rotundifolia , 
Normanbya merrillie . Pinanga insignis. 
