Title: sugarcane diseases
1SUGARCANE DISEASES
- BY
- JIMI PATEL
- Mo.No9924474599
-
2INTRODUCTION
- Sugarcane is not only cash crop for the growers,
but it is main source of white crystal sugar. It
also provides grower with a very good substitute
of sugar as gur and khandsari (brown sugar). - Sugarcane tops serve as fodder for cattle,
baggage and leaf trashes as fuel, stubble and
roots as organic manure and crop residues as
mulch and compost. - It may also be kept in mind that sugarcane leaves
are used as substrate for the artificial
cultivation of edible mushrooms.
3- There are many constrain, including the heavy
losses, caused by a number of diseases to the
sugarcane crop. - More than 50 diseases are reported in sugarcane,
fungi, bacteria, viruses and nematodes cause the
most destructive diseases. - These all diseases are injurious in some areas,
in some years and on some plant parts. - However, the causes, symptoms, transmission,
perpetuation and control measures of different
most important diseases of sugarcane are given as
bellow.
4WHIP SMUT (Ustilago scitaminea)
- Symptoms
- The affected canes produce long, black whip-like
and coiled or curved shoots, which are covered
with a thin silvery membrane, containing masses
of chlamydospores of the fungus.
5- The smutted shoots may arise from the top of the
cane or from lateral buds. Later on that membrane
ruptures and releases a multitude of spores,
which contaminate soil and the standing crop. - In certain cases, the infected plants remain
stunted in growth with increased tillering of
little value. The diseased plants are unfit for
use.
- Perpetuation
- The disease is carried over from year to year by
ratooning or planting sets taken from smutted
shoots of cane. Soil borne infection may also
takes place, while wind disseminates disease.
6Control Following measures are suggested for
prevention as well as control of the disease
1) Sets from smutted canes should not be used
for planting. 2) Seed-sets should be disinfected
either in 0.1 mercuric chloride or formaline
solution for 5 minutes followed by 2 hours
covering under a moist cloth. The other effective
chemicals available in market may also be
used. 3) Hot water treatment of sets at 52C for
18 minutes can help eliminate the internal
infection. 4) Smutted plants should be rouged out
and burnt before the bursting of the spores. 5)
Ratooning of the diseases crop should be
discoursed. 6)Use of resistant varieties should
be encouraged. 7) Planting should be done in
healthy soil. 8) Autumn planting of sugarcane
should be avoided.
7Rred Rot (Colletotrichum falcatum)
- Symptoms
-
- The disease first appears as red bright lesions
on mid rib of leaves and shows itself as drooping
and changing of colour of upper leaves.
8- Withering of the leaves proceeds downwards.
Usually third or the fourth leaf from the top is
affected and shows drying at the tip. - The pith becomes red and later on brown. In
sever cases complete destruction of the stools is
brought about. -
- Perpetuation
- The disease is perpetuated from year to year by
planting sets from infected canes and also
through the fungus that remains viable on
diseased canes lying in the field or ratooning of
the crop. - Control
- Non ratooning and use of resistant varieties are
recommended. Disinfecting of sets with effective
and easily available chemicals.
9SUGARCANE MOSAIC VIRUS (SCMV, Potyvirus group)
- Symptoms
- Mottling of young crown leaves showing a definite
pattern of alternating dark and light green
coloured patches of varying size and run parallel
to the midrib of leaf.
10Transmission Transmitted through mosaic
infected sets and an aphid. Alternate hosts
Maize and sorghum. Control Planting virus
free sets and avoid ratooning of diseased crop.
11GRASSY SHOOT DISEASE
- Symptoms
- This disease is characterized by the production
of numerous small and thin tillers having narrow
leaves with or without albinism.
12- Diseased plants exhibit varying degrees of loss
of chlorophyll, ranging from total green to
white. Premature excessive tillering gives a
crowded appearance like grass to the clump. - The root system of the affected plant reduced
and plants are usually reduced in height (stunted
growth). Affected clumps hardly produce one or
two weak canes. - In some cases, there is also formation of aerial
roots at the lower nodes.
13Transmission
- The grassy shoot disease is primarily
transmitted through the diseased seed material
and perpetuated through ratooning. This disease
is also transmitted by a) mechanically by Cutting
knife, b) Insects (aphids) and c) Dodder (root
parasite).
Control
Adopting one or more of the following measures
can minimize the disease incidence. 1)Use of
healthy diseased free planting material collected
from seed nursery for planting. 2) Roguing of
affected stools and destruction Mass
eradication may help consistent reduction in
inoculum in the area.
143) Head therapy seed/planting material should be
treated with hot water (50oC for 120 Min.) or
moist hot air (54oC hr, 2½ hrs.) that eliminates
the Pathogen from diseased seed materials.
Ratooning of affected crop must be avoided. Crop
rotation may be employed to reduce inoculum in
the field. 4) Control of insect pests.
15Reference
- Ahmad, I. 1988. Fungal Diseases of Sugarcane. In
Plant Disease Diagnosis Manual, Vol.2. CDRI,
NARC, PARC. Islamabad. - 2. Bhatti, I. M. and A. H. Soomro. 1996.
Agricultural inputs and field crop production in
Sindh. Agricultural Research Sindh, Hyderabad. - 3. Bhatti, I. M. and M. M. Jiskani. 1996. Modern
Agricultural Guide. Agricultural Research Sindh,
Hyderabad. - 4. Hafiz, A. 1986. Plant Diseases. PARC,
Islamabad. -
16Thank You