stem , leaf and sripe rust in wheat

1. Symptoms and important
characters of puccinia

2. puccinia
• Kingdom: Fungi
• Division: Basidiomycota
• Class: Pucciniomycetes
• Order: Pucciniales
• Family: Pucciniaceae
• Genus: Puccinia
• The genus contains about 4000 species.
• Puccinia is a genus of fungi. All species in this
genus are obligate plant pathogens and are known
as rusts.

3. • some species are autocious whereas some are
heteroecious
• Mainly 3 species are found to be devastating
wheat and other cereal crops through rust:
Puccinia graminis
: stem rust
P. recondita :
brown leaf rust
P. striformis :
yellow stripe rust

4. P. graminis
• P. graminis is an obligate
parasite, polymorphic
(several forms of spores
exists in its life cycle) and
heteroecious rust . It
affects wide range of hosts
including wheat, barley,
oats and rye.
• P. graminis tritici involves
in its life cycle two distinct
alternate host plants i.e.,
wheat (Triticum vulgare
fam. Poacae) and Barberry
(Berberis vulgaris fam.
Berberidaceae).

5. Symptoms
On Wheat:
• The symptoms of the disease appear as large, elongated and
brown pustules (uredosori) on the stem, leaf, sheath and leaf .
• Later on these brown pustules change into black coloured large
pustules (teleutosori)
• Grains of the infected plants are shriveled, much lighter in weight
and thus reducing the yield.
• The pathogen shows a balanced host parasitic relationship. Even
in the severe infection, the parasite does not cause much serious
damage except that the growth of the plants may be somewhat
retarded and the granis may be of reduced size and of poor quality

7. • On Barberry:
• Infection first starts on the
dorsal surface of the leaf in
the form of minute, dark
coloured and flask shaped
pycnia which appear as
yellow spots.
• Beneath Pycnia, on the
ventral surface, appear
cup like projections of
aecia or aecidia.

8. • Puccinia graminis causes stem rust of different
cereals like wheat, rye, oat etc.
• The isolate of wheat cannot infect oat or any other
host and vice versa, which indicate their host
specificity. i.e. biological specialisation.
• Thus P. graminis is a composite species.
• Based on pathogenecity, size of spores and cultural
variability, it has been divided into different
subspecies

9. • All the above biological strains/forms and physiological races have
the common barberry plant as their alternate i.e., secondary host.
• The differences they show are the graminaceous host.

10. • Wheat crops of Northern and Southern region of
India are largely affected by Puccinia graminis tritici.
• In South India (Nilgiri ranges) the disease appears
in November, thereby the vegetative growth of the
crop is affected much more than North India, where
the disease appears in late March or thereafter
when the crop is near its maturity.
• The rate of photosynthesis reduces greatly, thereby
causing much loss in yield

11. Wheat leaf rust
• Wheat leaf rust is a fungal disease that affects wheat, barley
and rye stems, leaves and grains.
• Infections can lead up to 20% yield loss, which is exacerbated by
dying leaves, which fertilize the fungus. The pathogen is :
• Puccinia triticina causes "black rust"
• P. recondita causes "brown rust"
• P. striiformis causes "yellow rust"
• It is the most prevalent of all the wheat rust diseases, occurring in
most wheat growing regions.
• It causes serious epidemics in North America, Mexico and South
America and is a devastating seasonal disease in India.
• All three types of Puccinia are heteroecious

12. Symptoms
• Small brown pustules develop on
the leaf blades in a random scatter
distribution.
• They may group into patches in
serious cases.
• Onset of the disease is slow but
accelerated in temperatures above
15 °C, making it a disease of the
mature cereal plant in summer,
usually too late to cause significant
damage in temperate areas.
• On barberry leaf the
disease appears as powdery
yellow spots with aecia being
dispersed from the underside of
the leaf
Losses of between 5 and 20% are
normal but may reach 50% in severe
cases.
Symptoms can range in severity from
barely aesthetic to
completely overrun on the leaf surface.

13. yellow stripe rust
• "Yellow rust" takes its
name from the
appearance of yellow-
colored stripes
produced parallel along
the venations of each
leaf blade.
• These yellow stripes
are actually
characteristic
of uredinia that produce
yellow
colored urediniospores

14. Symptoms
• stunted and weakened plants
• shriveled grains
• fewer spikes
• loss in number of grains per spike and grain weight.
• Losses can be 50%, but in severe situations 100% is
vulnerable.
• In countries where wheat is grown in winters or at high
elevations, yellow rust is a common threat, but not more
significant than wheat leaf rust and stem rust, which are
continuous threats in all wheat-growing countries.

17. References
• Wikipedia
• https://www.researchgate.net
• https://www.ncbi.nlm.nih.gov
• http://www.biologydiscussion.com/fungi/puccinia-
graminis

18. Thank you
Presented by :
Naincy Sharma
Id no. 2017002056