2. Red rot of sugarcane
CO: Colletotrichum falcatum
Red rot is one of the oldest known
diseases of sugarcane
It occurs in most cane-growing countries
Complete loss to cane production in
case of severe epidemic condition
It continues to be a threat in certain
subtropical countries
3. Symptoms
A) Symptoms on the leaves
First symptoms are seen after the rainy
season when plant growth stops and
sucrose formation begins
Loss of color and drooping of the 3rd or 4th
leaves are the earliest symptoms
Red patches with ash colored centre
develop on the mid-rib of leaf
The entire top become wither
4. Loss of color and
drooping of the
3rd or 4th leaves
Red patches
with ash colored
centre develop
on the mid-rib
Entire top
become wither
3rd
4th
5. B) Symptoms on the canes
The infected cane become shriveled and
such canes lighter in weight and easily
broken
When the diseased canes are splitted
open longitudinally, characteristic red
tissues are seen which are intermingled
with white tissues in the pith and
vascular region
The cavities filled with grayish or white
mycelium are found in the pith and minute,
velvety, dark dots (acervuli of the fungus)
are formed near the nodes of the diseased
canes and also in shrunken areas
6. Red tissues which
are intermingled
with white tissues
in the pith and
vascular region
Cavities filled
with grayish or
white mycelium
in the pith and
minute, velvety,
dark dots near
the nodes
7. Favorable conditions
Rain and irrigation water (carrying out
fungus or infectious material from one
plant to another or one field to the other)
Presence of Wind and insects (Stalk borer,
moth borer, sugarcane weevil)
Injury to sugarcane setts
9. Control measures
Diseasefreecane should be used as setts
Diseasedplantsshould be dug out & burnt
Low lying areas avoided forcultivation
A2-3 years rotationshouldbe followed
Ratooningshouldbe avoided
Use of resistantvarieties,eg. Iswardi2/54,Iswardi-16,iswardi-17,etc
SettstreatmentwithBavistin DF orKnowin50WPorAimcozim50WPor
Agben 50WPorForastin50WPor Genuine50WPor Cindazim50WP
orAgridazim50WPor Nayan 50WPor Evazim 50WPor Haydazim 50WP
or Gilzim50WPorOrgazim50WP@ 1glitof water
Application of the above mention fungicides @ 2ml/lit of water at 12-15
days interval for2-3 timesin the field
10. Smut of sugarcane
CO: Ustilago scitaminea
It causes 10-25% yield loss in
severe infections
Ratoon crop may suffer more
11. Symptoms
The most recognizable diagnostic feature
is the emergence of a “smut whip”
Spindle leaves are erect before the
whip emerges
Affected plant may produce tiller profusely
with the shoots being more spindly and
erect with small narrow leaves
(i.e., the cane appears “grass-like”)
12. Emergence of a
“smut whip”
Spindle leaves
are erect
before the whip
emerges
Affected plant produce tiller
profusely & grass-like
appearance
14. Control measures
Smuttedwhipsfromthe fieldshould be removed very carefullyandburnt
Avoid of practiceof ratooning
use resistantcultivars
The smuttedcanes should not be usedas settsforplanting
Settstreatedwith0.25%AgallolorAretanor inBM(4:4:50) for 5 min
Settsalsobe treatedwith0.1%Hgcl2 or1% formalinsolutionfor5 minutes
and followedby covering undermoist cloth for2 hours
Soaking of cane settsin solutionof triadimefonfungicide@ 2ml/litofwater
15. Wilt of sugarcane
CO: Fusarium sacchari
It causes 10-15% yield loss in
epidemic areas
16. Symptoms
The earliest symptom of the disease is the
stunting & unthrifty appearance of a few
isolated plants or small groups of plants
at half grown stage of the plants
The most striking symptom is the yellowing
and or withering of the top when the crop is
getting ready for harvesting. The canes
become light and hollow
The splitted cane shows brick red color
with individual vascular strands. There are
no white transverse bands as seen in the
red rot disease
17. Stunting & unthrifty
appearance of affected cane
Splitted cane
shows brick
red color with
individual
vascular
strands
Yellowing
and or
withering
of the top
18. Favorable conditions
Infected setts
injuries to setts
Biotic stresses like nematode, root borer,
termite, scales, mealy bugs etc
Abiotic stresses like drought and
water logging condition
Moisture stress coupled with high
temperature and low humidity reduces
plant resistance to wilt
19. Control measures
Crop debris should be destroyed
Healthysettsshould used forplantation
Proper maintenanceof soilmoistureand fertilitycanreduce the
disease incidence
Settsshould be takenfromborer infestationfreecanes
Ratooning shouldbe avoided
A2-3 years croprotationshould follow
Applicationof boron and manganese canreduce thewiltincidence
SettstreatmentwithBavistin DF orKnowin50WPorAimcozim
50WPor Forastin50WPorGenuine50WPorCindazim50WP@
1glit ofwater
Applicationof the above mentionfungicides@ 500g/hain the field
21. Symptoms
Typical disease symptoms are detected in
setts after 2-3 weeks of planting
Destroy the central soft portion i.e. paren-
chymatous tissues of the internodes by
rotting and then damages the buds
before germination
The rotten portion become red and emits
a characteristic smell of pineapple
(production of ethyl acetate by the fungus)
If germinates, the shoot may die after
reaching a height of one feet
23. Favorable conditions
Infected setts
injuries to setts
Stalk damaged by borers, rat damage
or any such injuries
Drought accelerates the damage
24. Plantinghealthysetts
The cutends of the settsshould paintedwithfungicidal
solutionorby coulter
Settsshould be treatedin hotwaterat52°C for 30 minutes
Setts treatment with Bavistin DF or Knowin 50WP or Aimcozim 50WP
orForastin 50WPor Genuine 50WPorCindazim50WP@1glitof water
Applicationof the above mentionfungicides@ 500g/hain the field
Control measures
25. Ratoon stunting of sugarcane
CO: Clavibacter xyli or
Leifsonia xyli subsp. Xyli
It causes yield reduction upto 40%
26. Symptoms
The diseased cane usually show stunted
growth, reduced tillering, thin canes with
shortened internodes & yellowish leaves
The typical symptoms of ratoon stunting
disease are found only after splitting
the cane longitudinally like two types
of discoloration are seen in the pith
In mature canes, orange red discoloration
of vascular bundles seen at the nodes
In young canes, pink color can be seen
at the nodes
27. Affected cane show stunted
growth, reduced tillering,
thin canes with shortened
internodes yellowish leaves
Orange red
discoloration
of vascular bundles
at the nodes in
mature cane
Pink color at the
nodes in young cane
29. Using the disease free setts. Raising of
disease free setts in nursery by the
following measures-
Proper drainage and optimum dosages of
fertilizers & irrigation should be provided
Timely hoeing and weeding
Weak plants should be uprooted & burnt
Rouging of stools showing symptoms of wilt,
red rot and smut should also be done
Any sett that fails to germinate within a
reasonable period should dug out and removed
Setts should be treated in hot water
at 52°C for 30 minutes
Use disease resistant varieties for cultivation
Control measures
30. Red stripe/ top rot of sugarcane
CO: Xanthomonas rubrilineans
31. Symptoms
Initially water-soaked yellowish stripes
occur on leaves, later become dark red
In severe infection, lateral buds show
reddening, terminal buds and spindle
leaves may die and causing top rot
The vascular bundles exude foul smelling
yellowish gum on cut
34. Control measures
Systematic cutting down and burning of
the affected shoots (reduces the spread
of the disease)
Disease resistant varieties should be used
35. Mosaic of sugarcane
Cause: Sugarcane mosaic virus
Vector: Different species of aphids
In mosaic susceptible varieties the
yield loss could be upto 10%
36. Symptoms
The most important symptom is the
appearance of pale green patches or
blotches in the green surface of the leaf
These patches are not uniform in
size and shape
Usually the patches are oval to elongated
and parallel to the midrib
The youngest unfolded leaves show the
mottling very clearly while the symptoms
are not very clear in the older leaves
38. Control measures
Healthy setts should be used for planting
Disease free nursery can be raised by
treating the setts with hot water
Systematic rouging should be followed if
the incidence is not very high
Alternate hosts should be destroyed
Disease resistant or tolerant varieties
should be used
39. White leaf of sugarcane
CA: Mycoplasma like organism (MLO)
Vector: Leafhoppers and psyllids
40. Symptom
Initially, a single white or cream line parallel to
the midrib occurs, which can be seen from either
side of the blade
Later, several straight white to light green to
yellow stripes develops parallel to the midrib
extending along the entire leaf length
A mottled pattern of normal or light green dot,
spot, streak or patch may develop on a white
background, varying in size and shape
The typical symptoms of sugarcane white leaf
(SWL) disease are total chlorosis of the leaf and
proliferation of tillers
42. Control measures
Healthy setts should be used for cultivation
Malathion should be sprayed @ 0.16%
during early stage of crop growth to
control insect vectors
Sett should be treated with hot water
at 54°C for one and half hours
43. Grassy shoot
CA: Mycoplasma like organism (MLO)
Vector: Aphids
In severe cases, yield loss
could be up to 40%
Its severity will be more
in ratoon crops
44. Symptoms
Profuse tillering and bunchy or grassy
appearance of the stools are the main symptom
Shoots growing from diseased shoots remains
dwarfed or stunted
The leaves appear yellowish and in some cases
may entirely devoid of any pigment (white leaf)
Leaves exhibit straight, narrow, long, white or
light green or yellowish streaks
45. Profuse tillering and
bunchy or grassy
appearance of the stools
Leaves exhibit
straight,
narrow, long,
white or light
green or
yellowish
streaks
Devoid of any
pigment (white leaf)
47. Control measures
Healthy setts should be used for cultivation
Malathion should be sprayed @ 0.16%
during early stage of crop growth
Sett should be treated with hot water
at 54°C for one and half hours