The document discusses three types of rust that infect sugarcane - brown rust, orange rust, and tawny rust. It describes the symptoms, distribution, pathogen, disease cycle, and management of sugarcane rust. Controlling the disease involves growing resistant varieties, removing infected plant material, and applying fungicides when conditions are favorable for rust development.

1. STUDENT COURSE TEACHER
Ms.THARANI. N Dr. S. PARTHASARATHY
ID. No. 2016021048 Asst. Prof . , (Plant Pathology)
COLLEGE OF AGRICULTURAL TECHNOLOGY
Affiliated to Tamil Nadu Agricultural University, Coimbatore
Kullapuram, Via Vaigai dam, Theni-625 562
RUSTS OF SUGARCANE

2. TYPES
There are 3 Rust species (types) that infect Sugarcane :
 Brown rust - Puccinia melanocephala
 Orange rust - Puccinia kuehnii
 Tawny rust - Macruropyxis fulva sp. nov

3. SIGNIFICANCE
• Sugarcane is one of the plants with the highest
bioconversion efficiency
• This crop is able to efficiently fix solar energy, yielding
some 55t of DM /ha annually
• It’s the world’s largest crop by production quantity
(1.9 billion t)
• Cane accounts for 79% of sugar produced
• Molasses, Baggase are some other products obtained
from this crop

4. • Since 1978, sugarcane production in Florida has been
threatened by sugarcane rust caused by Puccinia
melanocephela.
• This fungal pathogen is now found almost everywhere
sugarcane is grown.
• The spread of the disease has had considerable economic
impact
• During the 1987, 20% yield loss were noted due to the
occurrence of this disease and estimated economic losses
$40 million.
• Screening for resistance has become an integral part of
Florida sugarcane breeding programs

5. GLOBAL DISTRIBUTION
• Brown rust is widespread, infecting cane throughout
Africa, Asia, Australia and North and South America
for many years. It was first reported in South Africa in
1941.
• Orange rust was initially confined to Asia and
Australia, but was observed in Florida for the first time
in 2007 before spreading throughout the Americas. The
disease was later reported in western and central Africa
in 2010 but has not as yet been observed in southern
Africa.

6. • In 2008, a third, unknown rust was found on
sugarcane, Tawny rust (Macruropyxis fulva sp.
nov.) was observed on N25 in Swaziland and has
since spread to most cane-growing areas in South
Africa. The disease has also been reported in
Mozambique and Zimbabwe.

7. SYMPTOM
• Early symptoms of all three types of rust are similar and
include yellow flecking that can be seen on both leaf
surfaces.
• The flecks gradually elongate to form linear lesions that
are also visible on both leaf surfaces.
• These develop parallel to the leaf veins and darken from
the centre.
• Spores erupt from the lesions after 10-14 days, giving the
surface a rough appearance.
• As the disease progresses, each rust type presents its own
unique symptoms, making it possible to distinguish them
from each other

8. Brown Rust :
 Colour - Dark brown to reddish brown pustules
 Size - upto 20 mm long & 3 mm wide
 Distribution on leaf - more concentrated near leaf tip
 Attacks canes of less than 6 months

9. Orange Rust :
 Colour – orange to orange brown
 Size - upto 4 mm long and 3 mm wide
 Distribution on leaf – more concentrated towards the
leaf
 Usually attack canes which crossed 6 months

10. Tawny Rust :
 Colour - Dark brown to reddish brown may be some
purpling around the border
 Size - upto 20 mm long and 3 mm wide
 Distribution on leaf - more concentrated near the
leaf tip
 Attack canes at all the ages

11. PATHOGEN
Kingdom : Fungi
Phylum : Basidiomycota
Class : Pucciniomycetes
Order : Uredinales
Family : Pucciniaceae
Genus : Puccinia
Species : P. melanocephala H. & P. Syd 1907
P. Kuehnii (Krueg) Butler
P.erianthi Padw. & Khan.

12. PATHOGEN CHARACTERS
• Spermogonia and aecia unknown.
• Uredinia : Primarily hypophyllous (on lower surface of
leaves), cinnamon-brown, linear up to 4 mm
• Urediniospores : Obovoid or ellipsoidal, 25-39 × 17-28
µm, cinnamon to dark-brown, echinulate, germ pores 4-
5, equatorial, wall 0.8-2.3 µm; paraphyses hyaline to
golden, capitate or spathulate, 32-98 µm × 12-25 µm,
wall 1-2.8 µm thick, 4-15 µm at apex.

13. Uredinia of Puccinia melanocephala on Saccharum spp.

14. Urediniospore of Puccinia
melanocephala on
Saccharum spp.
SEM micrograph of
P.melanocephala
urediniospore illustrating
echinulate spines

15. • Telia : Hypophyllous, exposed, black to dark-brown
• Teliospores : 34-56 × 16-24 µm, mostly clavate,
walls 2-3.5 µm thick at sides, 2.5-8 µm at apex,
upper cell dark brown, lower cell paler, pedicels
brown, thin-walled, usually not collapsing, 4-17 µm
long; telial paraphyses long, capitate.

16. DISEASE CYCLE
• Sugarcane rust is an autoecious rust
• Uredospores are produced from the pustules that break
through the epidermis on the underside of the leaves
• Then the spores disperse from pustules via wind or rain
onto the leaves of a new host sugarcane
• The uredospores then germinate on the sugarcane leaves,
develop appresoria, infect new host via penetration on
plant’s stomata
• This cycle can be repeated throughout the year because
sugarcane growing areas are conducive for the growth of
this pathogen
• P. melanocephala infection is non-systemic

17. EPIDEMOLOGY
MODE OF SPREAD :
Rust produces spores that are microscopic, light and
hardy making them well adapted to rapid short and long
distance dispersal by wind and water splash.
Rust is not systemic and therefore does not spread by
planting seedcane from an infected field.

18. FAVOURABLE CONDITIONS :
• Leaf wetness and atmospheric temperature are the
environmental factors most influential for rust
development
• Cool (less than 25ºC), misty or light rain, high humidity
are conducive for development
• Studies have shown rust levels to be higher on sugarcane
grown on low pH soils than on high pH soils,
particularly when high levels of phosphorus and
potassium nutrients are present in the soil.

19. MANAGEMENT
• The best means of control for sugarcane rust is to grow
resistant varieties. Eg: N12 has good resistance to brown
rust .
• Other rust resistant varieties are co-421, co-467, co-575,
co-603, co-678, co-732, co-826, co-928
• Follow the long furrow or pair row method of planting.
• Removal of affected and dried leaves and destruction by
burning.
• After the harvest of diseased crop the leftover trash
should be burnt immediately .

20. • Foliar application of Mancozeb ( 0.15%) with
callixin (0.075%) 2 to 3 times at an interval of 10 to
12 days may be done immediately after the disease
appear.
• Applying following fungicides to actively growing
crops before or at the first sign of rust can reduce the
disease development .
TRADE NAME PRODUCER TARGET RATE APPLICATIONS
Abacus BASF Brown Rust
Tawny Rust
1.6 L/ha in
200 L water
2
Amistar Xtra Syngeta Brown rust
Orange rust
500 ML/ha in
400 L water
2

21. REFERENCES
• P.C.DAS, 2018, Plant Diseases, Kalyani
Publishers, New Delhi
• I.R.SAHA, 2010, Hand Book of Plant Diseases,
Kalyani Publishers, New Delhi