Puccinia graminis var. tritici is the fungus that causes wheat stem rust. It is an obligate parasite that infects wheat and barberry hosts. It has a complex life cycle involving five spore stages on the two hosts. On wheat, it produces urediospores and teliospores which lead to recurring infections. On barberry, it produces pycniospores and aeciospores which serve in the sexual reproduction and allow the disease cycle to continue across seasons.

1. Puccinia graminis var. tritici, symptoms, host range,
taxonomy and life cycle
COLLEGE OF AGRICULTURAL TECHNOLOGY
(Affiliated to Tamil Nadu Agricultural University, Coimbatore-3)
Kullapuram (Po),ViaVaigai Dam, Theni-625 562
STUDENTS
SUVETHA S
DEEPAN S
COURSE TEACHER
Dr. PARTHASARATHY.S
Asst. Professor (Plant Pathology)

2. HISTORY:
• The fungal ancestors of stem rust have infected
grasses for millions of years and wheat crops for as
long as they been grown.
• The ancient Romans created the Rust God
“Robigus”, Goddess “Robigo” and sacrificed red
coloured animals such as dogs, foxes, and cows
during the festival called the Robigalia to appease
the god, hoping to prevent destruction of Wheat
crops.

3. WHEAT STEM RUST

4. DISEASE NAME:
Wheat stem rust
PATHOGEN NAME:
Puccinia graminis var. tritici
HOST PLANT:
Wheat, Barberry

5. SYSTEMATIC POSITION
Kingdom : Fungi
Phylum : Basidiomycota
Subphylum : Pucciniomycotina
Class : Pucciniomycetes
Order : Pucciniales
Family : Pucciniaceae
Genus : Puccinia
Species : graminis

6. SYMPTOMS:
• Reddish brown rust pustules (Uredia) are
noticed mainly on the stem than leaf sheaths
and leaves.
• At maturity a mixture of brown and black
lesions (Telia) are seen.

7. SYMPTOM
In wheat
© fao. org

8. In Barberry
© Plant Science 4 U

9. Pathogen:
• It is obligate parasite.
• Puccinia graminis is heterocious.
• It is polycyclic, pathogen produce five kinds of
spores.
• Urediospores and teliospores on Wheat.
• Basidiospores from the teliospores found on the
infected fallen leaves in the soil.
• Pycniospores and aeciospores on Barberry.

10. STAGES OF LIFE CYCLE:
Stage 0:
Spermogonium, produces spermatia and
receptive hyphae.
Stage 1:
Aecium produce aeciospores.
Stage 2:
Uredium produce urediospores.
Stage 3:
Telium produce teliospores.
Stage 4:
Basidium produce basidiospores.

11. Urediospores: Oval, single celled, binucleate,
golden brown, pedicillate (repeating spores).
Teliospores: Two celled, dark brown, thick walled
apex pointed at tip (resting spores).
Basidiospores: Unicellular, round and uninucleate.
Pycniospores: Spherical, thin walled, hyaline,
unicellular, uninucleate.
Aeciospores: Unicellular, yellow, thick walled,
binucleate.

12. WHEAT
ASEXUAL SEXUAL
BARBERRY