Stem Rust of Wheat.Stem Rust of Wheat.

Submitted to:Submitted to: Muhammad Naveed Aslam sb. Muhammad Naveed Aslam sb.

ByBy Muhammad Ali Kharal.Muhammad Ali Kharal.

Roll # 19Roll # 19

CLASSIFICATION:CLASSIFICATION:Kingdom: FungiKingdom: Fungi

Division: EumycotaDivision: EumycotaSubdivision: Subdivision:

BasidiomycotinaBasidiomycotina

Class: TeliomycetesClass: TeliomycetesOrder: UredinalesOrder: Uredinales

Family: PucciniaceaeFamily: PucciniaceaeGenus: PucciniaGenus: Puccinia

Species : graminisSpecies : graminis

Puccinia graminisPuccinia graminis

INTRODUCTION:INTRODUCTION: Puccinia graminisPuccinia graminis is an obligate is an obligate parasite.parasite.

It is a heterocious parasite. It is a heterocious parasite. It’s life cycle on Wheat and on It’s life cycle on Wheat and on Barberry. Barberry.

Wheat is a primary host.Wheat is a primary host.Barberry is a secondary or alternate Barberry is a secondary or alternate host.host.

Spore-producing stagesSpore-producing stages Puccinia graminisPuccinia graminis is a is a

macrocyclic fungus producing macrocyclic fungus producing Spermagonia and aecia on Spermagonia and aecia on barberry bushes (barberry bushes (Berberis Berberis vulgarisvulgaris) and uredia and telia on ) and uredia and telia on Wheat plant.Wheat plant.

Symptoms.Symptoms.

On WHEAT plantOn WHEAT plant.. Pustules development parallel with the long Pustules development parallel with the long

axis of the setm,leaf and leaf sheath.axis of the setm,leaf and leaf sheath. The epidermis covering the pustule is later The epidermis covering the pustule is later

ruptured revealing a powdery of brick red-ruptured revealing a powdery of brick red-colored urediospores.colored urediospores.

When plant near maturity pustules produces When plant near maturity pustules produces black colored teliospores.black colored teliospores.

AeciosporesAeciospores geminates on Wheat stem or geminates on Wheat stem or leaf to form binucleate, dikaryotic leaf to form binucleate, dikaryotic filamentous well developed, branched, filamentous well developed, branched, intercellular mycelium.intercellular mycelium.

Many short sporophores and uredospores Many short sporophores and uredospores are produced that exert pressure on the are produced that exert pressure on the epidermis, which is pushed outward and epidermis, which is pushed outward and forms a uredial pustule.forms a uredial pustule.

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

http://en.wikipedia.org/wiki/File:Stem_rust_close_up.jpg

Puccinia Uredo- sporangium

Mycelium

Uredospore

Puccinia Uredo-

sporangium-Wheat

Uredospore are stalked, unicellular

oval, binucleate structures, rusty red in

colour.

Telial Stage:Telial Stage: When the wheat plant approaches maturity When the wheat plant approaches maturity

or when plant fails because of or when plant fails because of overwhelming infection, the uredia produce overwhelming infection, the uredia produce teliospores instead of urediospores.teliospores instead of urediospores.

Telia may also develop from recent Telia may also develop from recent urediospore infetions.urediospore infetions.

Teliospores don’t infect wheat.Teliospores don’t infect wheat. They are over wintering stage of fungus and They are over wintering stage of fungus and

also results in the production of new genetic also results in the production of new genetic recombination of the fungus.recombination of the fungus.

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

PucciniaPuccinia Telio Telio sporangiumsporangium

Teliospores

Teliospores Teliospores Dark Dark brown or black in brown or black in

colour. colour.

Germination of Teluto sporeGermination of Teluto spore On SoilOn Soil Favourable condition- Proper Favourable condition- Proper

Temperature, MoistureTemperature, Moisture Germination of Teluto spore- Germination of Teluto spore-

germination tube - Epibasidium germination tube - Epibasidium

Germination of TeliosporeGermination of Teliospore

Germination tube

Germinated Telio spore and formation of Germinated Telio spore and formation of Basidium & Basidio sporesBasidium & Basidio spores

Epibasidium

Basidiospore

Basidium

Symptoms.Symptoms.

On BARBERRY plant.On BARBERRY plant. Symptoms appear as yellowish to orange-Symptoms appear as yellowish to orange-

colored spots primarily on leaves.colored spots primarily on leaves. The infected tissues frequently swollen.The infected tissues frequently swollen. The torn whitish aecial wall usually protrudes The torn whitish aecial wall usually protrudes

at the margin of the aecia.at the margin of the aecia.

Stages of Puccinia Stages of Puccinia on Barberry leafon Barberry leaf

BasidiosporesBasidiospores landin on young barberry leaves landin on young barberry leaves germinate and penetrate the epidermal cells. germinate and penetrate the epidermal cells. After that mycelium grows intercellularly.After that mycelium grows intercellularly.

Within 3-4 days the mycelium develops in to Within 3-4 days the mycelium develops in to spermagonium, which ruptures the epidermis, spermagonium, which ruptures the epidermis, and its opening emerges on the surface of the and its opening emerges on the surface of the plant tissue.plant tissue.

Receptive hyphae and Spermatia, produced by Receptive hyphae and Spermatia, produced by spermagonium, fertilize and grow intercellularly spermagonium, fertilize and grow intercellularly towards lower side of leaf and develops towards lower side of leaf and develops Aecia.Aecia.

Receptive hyphae and SpermatiaReceptive hyphae and Spermatia

Spermatia Receptive hyphae

Develop-Develop-ment of ment of

AeciosporAeciosporangiumangium

Aecia bearingAecia bearingaeciospores (n+n)aeciospores (n+n)

•PucciniaPuccinia- Aecio sporangium on lower - Aecio sporangium on lower epidermisepidermis aeciospores infect primary host.aeciospores infect primary host.Aeciospores produced on alternate host Aeciospores produced on alternate host (e.g.,Barberry) infect primary host (e.g., (e.g.,Barberry) infect primary host (e.g., grasses)grasses)

Aeciospores- Aeciospores- round, yellowish round, yellowish red, Unicellular, red, Unicellular, binucleate, thick binucleate, thick walled, 6 germ walled, 6 germ pores.pores.

Germinate on Germinate on wheat plant.wheat plant.

AeciosporesAecidiosporangium

Puccinia- Puccinia- Polymorphic fungiPolymorphic fungi

Polymorphism: Various types of Polymorphism: Various types of spores produced during life cycle spores produced during life cycle according to hosts life cycle and according to hosts life cycle and climatic condition.climatic condition.

Known as Polymorphism.Known as Polymorphism. Fungi shows polymorphism known Fungi shows polymorphism known

as Polymorphic fungi.as Polymorphic fungi.

Puccinia Life Cycle

Puccinia life cyclePuccinia Life Cycle

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