2. Introduction:
Rusts are plant diseases caused by pathogenic fungi of the
order Pucciniales (previously also known as Uredinales).
Rust diseases of wheat are among the oldest plant diseases known to
humans.
Puccinia is an obligate parasite.
Required two alternate host
It has macro cyclic life cycle
Common name of “Rust” in other languages are Rati, Gerua, Tombora etc.
3. Characteristics of RUST disease:
• Rust is typically brownish-yellow to bright orange spots that form on
leaves. The spots are filled with a powdery substance. This substance
contains the spores that will spread to other plants if not treated.
Symptoms:
• Plants that have rust growth will not directly die from this type of fungi,
but it can contribute the decline of the plant.
• Some of the common symptoms include defoliation, stunted growth or
branch dieback. Leaving your plant exposed to rust will surely infect other
plants since rust is easily spread through the air.
4. Types of RUST:
Three types rust diseases that occur on wheat:
LEAF rust STRIPE rust STEM rust
Puccinia
graminis tritici
(black
Rust)
Puccinia rodentia
(Brown
Rust)
Puccinia
striiformis
(yellow
Rust)
6. Symptoms of STEM RUST:
Reddish brown pustules.
Large number of uredo spores are released
Brownish appearance even from distance.
Towards end black telia are produced for this
reason it
The site of infection is visible symptom of
disease.
9. Symptoms of LEAF RUST:
• Generally found on leaves ,glumes and awns.
• Symptoms begin as small circular to oval yellow
spots on the upper leaf surface.
• As the disease progresses, the spots develop into
orange-colored pustules that may be surrounded
by a yellow halo
• An “orange dust” on the leaf surface or on clothes,
hands, and equipment.
10.
11. Difference between STEM and
LEAF RUST
• Tiny orange lesions on seed heads in leaf rust do
not develop into erumpent pustules. But in stem
rust it developed
• This difference helps to distinguish leaf rust from
stem rust
13. Symptoms of STRIPE RUST:
• Presence of light yellow, straight-sided pustules
• Occur in stripes on leaves and heads.
• These elongate pustules are narrow and vary in
length.
• As the pustules mature, yellow-orange spores are
produced (Figure 1)
• The arrangement of pustules into stripes is an
important distinguishing characteristic of this
disease.
14.
15.
16. Disease Development:
• Temperatures conducive for germination and
growth of the pathogen are required for disease
development.
• Stem rust is a warm-temperature disease that
develops optimally between 65 and 85°F;
• Leaf rust develops optimally at temperatures
between 59 and 71°F, and
• Stripe rust is a lower-temperature disease that is
generally found to develop 50 to 59°F
17. CONTROL MEASURES:
• Resistance: Planting resistant varieties is the best
way to control wheat rusts. Resistant varieties
significantly reduce both infection and spore
production, which reduces spread to surrounding
fields
• Chemical: use different fungicide is very effective.
• Others: Crop rotations and modified tillage
practices are not effective against rusts
