August 23, 2005
From: Dick Hamilton, ProMED-mail Plant Disease Moderator

CORRECTION

Yellow rust, also known as stripe rust, is caused by _Puccinia striiformis_  f. sp. _tritici_, one of the most widespread wheat diseases in the world. Yield losses can be as much as 40 percent. This pathogen reproduces
asexually, with no known alternate host, and spreads by means of airborne dicaryotic uredospores. On the other hand, brown rust, also known as leaf rust, is caused by _Puccinia triticina_.

Most cereal rust researchers have agreed to discontinue the use of _Puccinia recondita_ f.sp. _tritici_. Thus, brown rust and leaf rust are the same disease. The use of 2 names for the same disease does not help indexing and bibliographical search, but those names have been used for more than a century, and it would be difficult to drop one rather than the other.

I am indebted to Ivan Sache for clarifying the taxonomic status of the stripe rust pathogen.

Dick Hamilton - Mod.DH
ProMED-mail Plant Disease Moderator
Senior Research Scientist (Retired)
Research Branch, Agriculture and Agri-Food Canada
Richmond, BC CANADA
<hamilton@promedmail.org>

[see also in the archive:
2001
Brown rust, wheat - Russia (E. Siberia) 20010724.1442
2000
Leaf rust, wheat - Australia 20001215.2187]

August 22, 2005
From: ProMED-mail <promed@promedmail.org>
Source: Kazinform, 12 Aug 2005 [edited] <http://www.inform.kz/showarticle.php?lang=eng&id=134593>

To date 1 139 300 ha of Kazakhstan lands have been treated against rust and Septoria diseases of cereal crops, according to the director of protection and phytosanitary control of the Agriculture Ministry of Kazakhstan, Saktash Khasenov.

According to Khasenov, rust and Septoria diseases were expected to cover about 1 551 000 ha. However, weather conditions turned out to be favorable for development of diseases, and the total area of affected land was about
2 550 000 ha. Most of the infected areas were in the northern grain seeding regions. In the Kostanay region, a state of emergency was declared.

Taking into account the available [funds?] allocated for the "Plant protection" program, 795 000 ha were cultivated. 344 030 ha underwent chemical treatment at the expense of the agricultural producers.

[Byline: Nazym Shakhanova]

--
ProMED-mail
<promed@promedmail.org>

[In Central Asia, yellow rust (_Puccinia triticina_), tan spot (_Pyrenophora triticirepentis_), common bunt (_Tilletia tritici_, syn. _T. caries_), and _T. laevis_ (syn. _T. foetida_) are major foliar diseases of spring wheat, although Septoria leaf blotch (_Septoria tritici_ and _S. nodorum_), leaf rust (_Puccinia recondita_ f. sp. _tritici_), and cereal
cyst nematode (_Heterodera latipons_) also occur in some areas. Yellow rust and leaf rust are also very important in the Caucasian countries.

As researchers develop new varieties resistant to these diseases, progress is tested through a step-by-step evaluation at different locations in the region. In the first step, resistance to yellow rust, leaf rust, stem rust,
Septoria leaf blotch, cereal cyst nematode, and common bunt is evaluated at Tel Hadya, ICARDA's headquarters, where wheat nurseries are artificially inoculated with these diseases. In the 2nd phase, varieties identified as resistant are further screened for resistance to different diseases in heavily infected areas in different countries in Central and West Asia and North Africa (CWANA) in collaboration with local scientists at 3 to 5 sites per country.

It is difficult to assess disease loss given the information available. The fact that about 350 000 ha. were treated with fungicides indicates that farmers needed to try to control the diseases affecting their crops.

Links:
<http://www.icarda.org/ICARDAandCIMMYT/P08.htm>
<http://www.oznet.ksu.edu/path-ext/factSheets/wheat/wheat%20Leaf%20Rust.asp>
- Mod.DH]

[see also in the archive:
2001
Brown rust, wheat - Russia (E. Siberia) 20010724.1442
2000
Leaf rust, wheat - Australia 20001215.2187
1999
Crop diseases - Canada (Manitoba) (02) 19990825.1484
Crop diseases - Canada (Manitoba) 19990816.1417
Leaf rust, wheat - Canada 19991015.1833]