The Hawaiian gazette., 1875-07-14
Rust i'm Sugar Cane.

It would appear from an article in the Bris-
bane QuseRSl1ldsr, that the sugar planters of
that colony have cane disease to contend
with, an account of which may interest our
readers. 1t is described by a writer in the
paper referred to, who says: "This so-called
rust in cane first appeared in Queensland
about three years ago, and was then confined
to small patches, principally of the Bourbon
variety. When the plant is attacked, the
leaves show brown spots; in severe cases, the
whole leaf becomes brown or dry, suggestive
of the name, rust The cane also shows
discolored spots, and rapidly loses density.
The roots, on examination, will at this stage
be found in q state Of decomposition, and even
the aerial roots or radicals Immediately above
ground, will be found to have lost their vitali-
ty, the spongioles being completely decayed.
Various opinions have from time to time,
through the press of the colony, been hazarded
as to the cause of this disease, but none claim
ing positively to have mastered the subject
Some think the disease is atmospheric and
contagious. Others attribute the cause to fungi.
Some to want of drainage and improper culti-
walton. Mr. W. r. Alexander, in his articles
lately published in The Qnesnsl1ader, gives a
most intelligent and exhaustive theory of the
cause, generally, Of that disease in plants, and
notably wheat and potatoes in particular; and
he supports his theory by the practical tests of
numerous writers on the subject, particularly
in America, the cure in all cases being lime,
and an absence Of that salt in the soil the
cause of the disease. 1 am sorry to say, how
ever, that neither a liberal use of lime, nor its
existence in the soil in large quantities either
prevents or cures the disease in cane. On
plantation in my neighborhoOd the first canes
showing symptoms of rust grew on soil
abundantly mixed with sea shells; and as a
corroborative proof that the cane had assimi-
lated large quantity of the lime from the soil
scarcely any was required for the complete
clarifcation of its juice Nor is the disease
conveyed by atmospheric agency, from the fact
that have rusted cane, and cane free from
rust growing in alternate rows, with the leaves
of the healthy and the rusted canes intermin-
Cling. This same fact also dispels the theory
of parasitic fungi. The diseased cane is the
Salangore, the healthy cane is the Meera, in this
instance. have also ascertained that drain
age, high cultivation, and land most Astounding
in plant-foOd instance newly-cultivated scrub
lands) accelerate the disease. According to
Schleiden, plants in a high state of cultivation
are all more or less in a condition predisposed
to disease. He says there is an unnatural and
excessive development Of particular structures
or particular substances and thus the eduili
brium being destroyed, the plants are liable to
suffer from injurious external influences; he
further says the same of wheat, rye, or barley,
sown in land the first year after it has been
manured, or when the climate is very unlike
the original one of the plant, as in the case of
maize in most parts of Europe. Gentlemen,
my belief is that the disease in cane Will be
found to be simply the effects of climate, it
viii be found due to the sudden transitions of
our climate from great heat to a low tempera-
ture, and from extreme and protracted drought
to a superabundance of moisture Thus frost
coming on in spring, after the sap begins to
flow, causes injury, and either kills the plant
or weakens its constitution, rendering it liable
to disease. The plant thus enfeebled, meets,
as in the months of November and December,
extreme drought and heat, not drop of mois
ture in the soil, and the thermometer ranging
from 80 : to llOo in the sun, scorching not
only leaves and stalk, but roots Of cane (which
you are aware, in this plant, seek for food
near the surface Of the soiI). When, succeed
ing such state Of things, an abundant rain
fall takes place, as in February last, starvation
of the plant is succeeded by plentiful moisture,
and as cane is gross feeder, and absorbs
great deal of water, which 1t consumes both in |
its vegetation and in the formation of its juices
the sudden reaction from starvation to a super
abundance of moisture Tin which in rich soils
the cane rapidly assimilates plant-foOd) proves
too much for the weakened condition Of the |
plant, sudden reaction takes place in the eel
lulose and IN the contents of the cells, which |
speedily leads to decay.
"Now, gentlemen, for the remedy-and It is
most fortunate for planters there is one; it is !