Stem Rust of Wheat.

2. Stem Rust of Wheat. Submitted to: Muhammad Naveed Aslam sb. ByMuhammad Ali Kharal. Roll # 19

3. PUCCINIA • CLASSIFICATION: • Kingdom: Fungi • Division: Eumycota • Subdivision: Basidiomycotina

4. Class: Teliomycetes • Order: Uredinales • Family: Pucciniaceae • Genus: Puccinia • Species : graminis Puccinia graminis

5. INTRODUCTION: Puccinia graminis is an obligate parasite. It is a heterocious parasite. It’s life cycle on Wheat and on Barberry. Wheat is a primary host. Barberry is a secondary or alternate host.

6. Spore-producing stages • Puccinia graminis is a macrocyclic fungus producing Spermagonia and aecia on barberry bushes (Berberis vulgaris) and uredia and telia on Wheat plant.

7. Symptoms. On WHEAT plant. • Pustules development parallel with the long axis of the setm,leaf and leaf sheath. • The epidermis covering the pustule is later ruptured revealing a powdery of brick red-colored urediospores. • When plant near maturity pustules produces black colored teliospores.

8. Puccinia- Infected Plant Parts

9. Stages on Wheat • Aeciospores geminates on Wheat stem or leaf to form binucleate, dikaryotic filamentous well developed, branched, intercellular mycelium. • Many short sporophores and uredospores are produced that exert pressure on the epidermis, which is pushed outward and forms a uredial pustule.

10. Finally, the epidermis is broken irregularly, revealing several hundred thousand rust-colored uredospores, which give a powdery appearance to the uredium.

11. Puccinia- Rust diseases Uredosporangium

12. Uredospore Puccinia Uredo- sporangium Mycelium

13. Puccinia Uredo-sporangium-Wheat

14. Uredosporeare stalked, unicellular oval, binucleate structures, rusty red in colour.

15. Telial Stage: • When the wheat plant approaches maturity or when plant fails because of overwhelming infection, the uredia produce teliospores instead of urediospores. • Telia may also develop from recent urediospore infetions. • Teliospores don’t infect wheat. • They are over wintering stage of fungus and also results in the production of new genetic recombination of the fungus.

16. Telia bearing teliospores (n+n>2n)

17. Puccinia Telio sporangium Teliospores

18. Teliospores Dark brown or black in colour.

19. Germination of Teluto spore • On Soil • Favourable condition- Proper Temperature, Moisture • Germination of Teluto spore- germination tube - Epibasidium

20. Germination of Teliospore Germination tube

21. Germinated Telio spore and formation of Basidium & Basidio spores Basidiospore Epibasidium Basidium

22. Symptoms. On BARBERRY plant. • Symptoms appear as yellowish to orange-colored spots primarily on leaves. • The infected tissues frequently swollen. • The torn whitish aecial wall usually protrudes at the margin of the aecia.

23. Stages of Puccinia on Barberry leaf • Basidiospores landin on young barberry leaves germinate and penetrate the epidermal cells. After that mycelium grows intercellularly. • Within 3-4 days the mycelium develops in to spermagonium, which ruptures the epidermis, and its opening emerges on the surface of the plant tissue. • Receptive hyphae and Spermatia, produced by spermagonium, fertilize and grow intercellularly towards lower side of leaf and develops Aecia.

24. Receptive hyphae and Spermatia Receptive hyphae Spermatia

25. Develop-ment of Aeciosporangium

26. Aecia bearingaeciospores (n+n)

27. Puccinia- Aecio sporangium on lower epidermisaeciospores infect primary host.Aeciospores produced on alternate host (e.g.,Barberry) infect primary host (e.g., grasses)

28. Aeciospores- round, yellowish red, Unicellular, binucleate, thick walled, 6 germ pores. • Germinate on wheat plant. Aecidiosporangium Aeciospores

29. Puccinia- Polymorphic fungi • Polymorphism: Various types of spores produced during life cycle according to hosts life cycle and climatic condition. • Known as Polymorphism. • Fungi shows polymorphism known as Polymorphic fungi.

30. Puccinia Life Cycle

31. Puccinia life cycle Puccinia Life Cycle

32. Thank you !