Black stem rust of wheat

Black Stem Rust of Wheat

This rust usually appears late in season. It is often not seen until March in northern India by the eating time of crops.

Black stem rust of wheat 🌾

Symptoms Of Black Stem Rust of wheat

The rust appears in the form of elongated raddish brown pastules ( Uridia ).
Primarily on the stem and followed by the leaf sheath and leaf.
Stem is most severally attacked.
The Uridia frequently merged with each other soon brust exposing the brown powder of uridiospores surrounding by reptured Epidermal fringes.

Another kinds of pastules ( Telia ) develop letter in the same source or independently.
Telia are darker and by this time pastules channel from brown to almost black colour.
These are also most promenent culms followed by leaf sheath and leaf.

Causal Organism of black stem rust of wheat :

Black stem rust is caused by Puccinia graministtritci.
The hypha in wheat leafs small round or branched but haustoria from this Mycelium Uridiospores develop in Uredospores beneath the Epidermis.
Each Uredospores is oval staked brown body 25 to 30 × 70 -20mm.
Single Uridiospores cell with echinulate exospore.
These are 4 germpore along and equatorial band.
As host Epidermis reptured, Uridiospores are disseminated by wind.
They germinated on healthy parts of plants causing Secondary infection.
Telia however are like uredia more frequent on stem.
Telia are oblong to liniour dark brown to black exposed through the rifted Epidermis.
Each teliospore is staked two celled with a thick smooth wall.
The apex is round or pointed.
Each cell has a germpore.
Teliospore under go a period of rust four several month.
In India these spores are unable to survive the hot summer temperature following the harvesting the crop.
If condition are suitable each cell of teliospore germinate to farm a four cell promiulium from each promiulium 4 haploid basidiospores are formed in stigma.
Berberis vulgaris the common barberry growing in heals is the alternate host.
On germination basidiospores give rise to haploid Mycelia inside bar berry leaf.
This Mycelium develop special structures on both side of leaf of barberry.
Puccinia are flasked shaped Structure on the upper surface.
Inside it are Spermatia sexual fusion occurs between Spermatia and flexous hypha of pycinidia of opposite stains.
The dicariotic Mycelium thus developed then formed another types a Structure accia. On the lower surface of leaf.

Accia are yellow cup shaped respecticals inclosed by peridium.
Each aecial cup contains chains of aeciospores.
The aeciospores are yellow echinulate and with 6 germspore.
Aeciospore does infect wheat leafs through stomata.
The cycle may be completed with the Uridiospores only and it usually occur in India.