Abstract only

Pgt race TTKSK (named Ug99) with virulence to Sr31 and some other resistance genes is considered a global threat to wheat production. It was first detected in Iran in 2007. From 2008 to 2010 a national surveillance program was conducted in major wheat-growing areas in south, southwest, west, north and northeast parts of the country. Race identifications of 100 samples were made using the revised North American differential set. In total, 37 races were identified, with races TTTTC and TKTTC being the most predominant at frequencies of 25% and 12%, respectively. Race TTTTC was detected in almost all surveyed regions whereas race TTKSK was identified in 6 samples collected from Ahwaz and Dashte Azadegan in Khuzestan province (in the south) in 2009. Following its first detection in 2007 TTKSK was identified in Boroujerd (Lorestan province in the southwest) in 2009 and 2010. Sr24 remains effective against all races. Since almost all current Iranian commercial cultivars are susceptible to Ug99, unfavorable environmental conditions and low inoculum loads are considered the major factors that have limited spread of race Ug99 in Iran.

Global Wheat Program

Text in English

INT3301

CIMMYT Staff Publications Collection