268 
Journal of Agricultural Research 
Vol. XXV, No. 6 
enlarges until the pod becomes blackened. In excessive damp weather, 
a mass of mycelium with conidia may be produced on the surface of 
diseased fruit (PI. 2, B). The mycelium invades the rind, passing into 
the seed. Diseased pods may fall or remain on the tree, drying up and 
becoming mummified. Flowers and stems may be attacked and killed 
by the fungus. The canker is found on young twigs, older branches, and 
the trunks of trees. Diseased twigs are characterized by browning of 
the leaves, dying of the tips, and shrivelling of the diseased wood. The 
first evidence of a canker is the appearance of a darker than normal 
color on the bark. The infected area may then turn brownish. A 
shrinking of the diseased area and a definite line of demarcation is usu¬ 
ally produced, showing the limits of the infection. In advanced stages 
the bark may exude an amber fluid and later may crack and scale. The 
infection has been observed to spread from diseased pods into the branches 
or trunk. A true cankered condition is not always produced. Internal 
symptoms are characterized by a browning and blackening of the in¬ 
fected bark and wood (PI. 2, A).' 
The fungus from coconut, used for the comparative study, was isolated 
from an infected coconut tree on March 11, 1919. The diseased tree 
was located in a plantation near Lilio, Laguna Province, P. I., a region in 
which sporadic epidemics of the disease have been recorded since 1908. 
The fungus from cacao was isolated from a diseased cacao pod col¬ 
lected in the plantings near Lbs Banos, Laguna Province, P. I., during 
1917. The disease is present there in a severe form throughout the 
year, causing most damage during the rainy season. 
COMPARATIVE STUDY OF THE FUNGUS ON BOTH HOSTS 
FIELD CHARACTERISTICS 
On coconuts the single terminal bud of the tree is affected. A white 
mycelial felt may or may not be present on the young, folded, diseased 
leaves of the bud. Microscopic examination of the infected parts of the 
leaves, growing point, and surrounding tissue shows the presence of a 
granular, nonseptate mycelium in the intercellular spaces (PI. 8, A). 
Fingerlike haustoria are produced in abundance, penetrating the host 
cells (PI. 8, B). Chlamydospores, in limited numbers, have been ob¬ 
served in the infected buds some 60 cm. above the growing point. The 
writer has never observed the lateral penetration into the tender bud 
through the leaf bases. The penetration in all cases observed appeared 
to be a vertical, downward one, along the central leaf sheaths into the 
bud. 
Diseased cacao pods may be covered with a mass of mycelium with 
conidia, but usually there is no macroscopic evidence of mycelium (Pi. 
2, B). Conidia are produced in abundance on the surface of the fruit. 
Microscopic examination of the interior of diseased pods shows the pres¬ 
ence of a granular, nonseptate, intercellular mycelium and usually a mass 
of chlamydospores (PI. 8, C). In cankered areas the mycelium develops 
primarily internally in the diseased tissue. Rarely, as under excessive 
damp conditions, the hyphae are produced on the surface. 
INFECTION EXPERIMENTS 
The evidence given before by the writer (7) is sufficient to prove that 
the organism from coconut budrot can produce the disease in coconut 
seedlings and older trees through injuries. Further infection experi- 
