Types of wheat rust and their management

 

Wheat rusts

Class: Basidiomecetes

Order: Uredinales

Family: Pucciniaceae

Rust is a serious threat to wheat all over the country. Losses due to rusts vary from 40-70%.

Rust types:

1.       Yellow/stripe rust

2.       Brown/leaf rust

3.       Stem/Black rust

Yellow rust

Causal organism: Puccinia striiformis

Symptoms:

·         Yellow colored uredia appear in parallel lines on leaves.

·         Yellow spore mass is dispersed by wind.

·         Black patches of telia appear on lower side of leaves.

·         Poor root system

Epidemiology:

·         Uredospores are main source of inoculum.

·         Disease appear in December and January.

·         Free water on leaves and temperature <25° favor the disease.

Brown rust

Causal organism: Puccinia triticina

Symptoms:

·         Bright orange to brown colored uredia are found on leaves in scattered form.

·         Spores are bigger than yellow rust spores

Epidemiology:

·         Appear in February

·         Free water on leaves and 18.3-23.9°c temperature favor the disease epidemic.

Stem rust

Causal organism: Puccinia graminis

Symptoms:

·         Brown pustules appeared on stalk and leaf sheath.

·         Telia are produced and black colored pustules are formed.

·         Grains are shriveled.

Epidemiology:

·         Appear in March.

·         Free water on plants and 18-29.5°c temperature favors the disease.

·         Aeciospores from barberry are primary source of inoculum.

Management of rusts

v  Use resistant varieties

v  Destroy alternate host

v  Judicious use of potash minimizes disease

v  Use fungicides i.e. carbendazim, propiconazole, tebuconazole, Azoxystrobin

Errors are accepted.