The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1904-04-04


no alarm to the producers of either
sugar or coffee since both diseases have
| been well worked out and respond to
active measures of control as outlined
below.
THE PINEAPPLE DISEASE OF
SUGAR CANE.
| An outbreak of a disease of sugar
cane on one of the windward planta-
lions of Hawaii was reported to this
station In November, 1903. The Ento-
| mologist, Mr.. d. L. Van Dine, visited
the locality and made an examination.
| Specimens of the diseased cane were re-
ferred to DR.. Albert F. Woods, Plant
Patholopist and Psychologist of the u.
S. Department of Agriculture at Wash
ington, D. c., who reported the cane
to be infested with a fungus, Thielaviop-
sis ethaceticus Went, which has caused
more or less serious losses in the cane
fields of Java, the West Indies and other
cane-sugar producing countries.
Fungus is the name applied by bota-
nists to certain lower orders of plants
loften microscopic and invisible to the
naked eye), which derive their food
either from dead or decaying organic
matter or by parasitism upon other
plants or animals. Fungi do not contain
chlorophyl, the green coloring matter in
the leaves of Towering plants and ferns
Common examples of fungi are toad
stools, moulds, potato blight, etc.
This cane-disease has been reported
from nearly every cane growing coun-
try in the world. The literature of
plant diseases contains abundant refer
ences to It 1t exists in number of
forms which have been described under
different names, according to whether
its appearance has been noted on differ
e11t parts of the cane plant In its most
serious form this fungus attacks the
young seed cane. or so injuries the eye
itself that the cane fails to terminate
1t has been noted in ether countries
that serious outbreaks almost invariably
follow the work of some insect pest,
either the cane borer or some external
feeder like the leaf-hopper.
The fungus is truly parasitic. The
fine microscopic white threads which
constitute the vegetative stage of the
fungus, as soon as they have gained en-
trance into the tissues of the cane
through any artificial wound or pune
ture of the epidermis such as that made.
by leaf-hopper or cane borer, branch
and increase in number until the whole
interior of the cane stalk is filed with
the mass.
The affected parts, especially the
leaves, leaf-sheaths and younger and
more tender portions Of the cane itself
show bright reddish discoloration ex-
ternally, and if the stalk is cut across.
or split lengthwayS, reddish streaks all
through the interior tissues. When
young plant cane is infected the leaves
become light yellowish green and the
plant soon dies. If infected seed is
planted the eyes often fail to grow so
that the field must be entirely replanted
Cane seed the vitality of which has been
affected by this fungus after planting,
will be found upon examination to be
covered with a mass of fine white
threads, the myceliurn or vegetative
stage OF the fungus, while the rind of
the cane IS covered with little raised
blisters. These small pustules, plainly
visible to the naked eye are character
istic OF this disease.
Older cane when seriously attacked
presents a peculiar stunted appearance,
sudden decrease in the thickness and
length of the joints, dying of the leaves
and. finally, if the fungus gains the up
per hand the whole plant is killed into
the ground. Such killing of the cane
by his fungus was observed. during
February, 1904, in fields where the vigor
of the cane had been seriously impaired
by the leaf-hopper. The fruiting stage
of the fungus appears on the rind of the
dead cane-stalks in the same form as
on seed cane, as minute pustules or bis
tiers fom the middle of which exudes
black sooty mass consisting of millions
of very minute obIong 7spores,-the
seeds" of the fungus, ready to be
blown about by the wind or carried to
other cane plants on the bodies of in
sects.
This disease has been known as
Pineapple d&ease,' the name being ap-
piled because of the pineapple odor of
freshly cut stalks of cane infected with
the fungus. This odor is really due to
the formation of acetic ether by the
fungus from the saccharine substances
within the cane stalk
In some localities in Hawaii, this
disease has been termed "Eleau," but in
the opinion of the writer that name
more properly applies to fungus disease
which causes cumming up of the leaf
sheath, so that when the cane is stripped
the hbres of the sheath remain adherent
to the cane.
Il has been noted in both the West
Indies and Java that where there is any
considerable amount of this disease
present in the fields that are being har-
vested. there is a marked retardation of
specialization of the juice.
For the protection of cane seed against
this fungus it has been recommended in
Java that the cut ends of the seed be
coated with tar before planting. How
ard investigated methods of prevention
and found that better results were OBJ
tanned by dipping the seed in Bordeaux
mixture or in a combination OF Bor-
deaux mixture and tar than by the use
of tar Alone. He also recommends the
use of top seed. because the top joints
contain less sugar than the lower joints. |
and are hence less liable to be attacked |
hx, tI,a f,,nur,,S