Puccinia graminis is a fungus that causes stem rust disease in cereal crops such as wheat and barley. It has a complex life cycle involving two hosts - wheat is the primary host and barberry is the secondary host. On wheat, it forms brown to black pustules above ground that result in reduced growth and seed size. On barberry, it forms flask-shaped structures on one side and spore-producing structures on the other. Its life cycle involves five different spore types that allow it to complete its life cycle between the two hosts.

1. Systematic position and life cycle of
Puccinia
Sankrita Gaonkar
Assistant Professor in Botany
sankrita002@gmail.com

2. Contents
• Systematic position of Puccinia
• Life cycle of Puccinia
• References

3. Puccinia
Systematic position:
• Class: Basidiomycetes
• Order: Pucciniales
• Family: Pucciniaceae
• Genus: Puccinia
Features:
• Genus Puccinia consists of more than 4000 different species all of which
are plant pathogens.
• These are known to cause rusts in both monocotyledons and dicotyledons.
• Major pathogen, P. graminis (Stem rust) affects cereal crops such as wheat,
barley etc.

4. Puccinia graminis
• It is an obligate parasite of wheat causing stem rust
disease.
• Its life cycle consists of two hosts namely,
Wheat – Primary host
Barberry – Secondary host
• Stem rust affects parts of plants that are above ground.
• In wheat it results in formation of brown to black
elongated pustules.
• In barberry it forms flask shaped pycnia at dorsal and
aecia on ventral side
• Infection of P. graminis results in retarded growth and
reduced seed size in wheat.

5. 5 types of spores in life cycle of Puccinia graminis:
• Pycnidiospores or Spermatia (uninucleate) – spermagonia
• Aecidiospores (binucleate) – aecidia
• Uredospores (binucleate) – on dikaryotic mycelium
• Teleutospores or teliospores (binucleate) – on dikaryotic mycelium
• Basidiospores (uninucleate) – basidia

6. Life cycle of Puccinia graminis

8. References
• https://www.cusb.ac.in/images/cusb-files/2020/el/lsc/amt/Puccinia.pdf
• Vashishta B.R., Sinha A.K. and Singh V.P. 2012. Botany for degree
students: Algae. S. Chand & company ltd.