Race Ug99 of Puccinia graminis f. sp. tritici, recognized for possessing virulence to Sr31, was first reported in Uganda in 1999 (Pretorius et al., 2000). Based on the North American stem rust nomenclature system of 16 differential lines (Roelfs and Martens, 1988; Roelfs et al., 1993), Ug99 is identified as race TTKS (Wanyera et al., 2006). Isolates with virulence similar to Ug99 were identifie...

Quantitative adult plant resistance (APR) to stem rust (Puccinia graminis f. sp. tritici) is an important breeding target in wheat (Triticum aestivum L.) and a potential target for genomic selection (GS). To evaluate the relative importance of known APR loci in applying GS, we characterized a set of CIMMYT germplasm at important APR loci and on a genome-wide profile using genotyping-by-sequenci...

Stem rust (caused by Puccinia graminis Pers.:Pers. f. sp. tritici Eriks. & E. Henn.), a devastating disease of wheat (Triticum aestivum L.), was effectively controlled worldwide for the past 50 yr by deployment of stem rust resistance (Sr) genes in wheat cultivars. However, a new stem rust race, TTKSK (known as Ug99 or TTKS) that emerged in eastern Africa, is a cause of concern because it has b...

A rust fungus was found causing stem cankers on 1to 5-year-old stems of Salix elbursensis in the north west of Iran. The rust also forms uredinia on leaves and flowers of the host willow. Light and scanning electron microscopy revealed that the new rust is morphologically distinct from several Melampsora species occurring on the willows taxonomically close to S. elbursensis, but indistinguishab...

wheat is the most important crop of iran and black or stem rust disease is one of the most severe diseases threatning the wheat production. in order to identify new resistant sources against the new race of stem rust virulent on plant with sr 31gene, the selected iranian landraces accessions of national plant gene bank of iran wheat collection were evaluated. the most virulent isolate of puccin...

ALTHOUGH genes governing many characters have been transferred between species, the inheritance of only a few of these genes has been studied in detail in their new genetic backgrounds. ALLARD and SHANDS (1954) reported that the stem rust resistance transferred from Triticum timopheeui Zhuk. to a common wheat variety C.I. 12633 was controlled in certain hybrids by duplicate dominant genes linke...

Zhong, S., Leng, Y., Friesen, T. L., Faris, J. D., and Szabo, L. J. 2009. Development and characterization of expressed sequence tag-derived microsatellite markers for the wheat stem rust fungus Puccinia graminis f. sp. tritici. Phytopathology 99:282-289. Puccinia graminis f. sp. tritici is the causal agent of stem rust disease in wheat. The rust fungus has caused devastating disease epidemics ...

Singh, R. P., Bechere, E., and Abdalla, 0. 1992. Genetic analysis of resistance to stem rust in ten durum wheats. Phytopathology 82:919-922. Durum wheat (Triticum turgidum L.) cultivars derived from CIMMYT present in Mexicali 75, Diver, Somorguho, and Morus together with (International Maize and Wheat Improvement Center) germplasm are an unidentified gene, SrC, and in Altar 84, Carcomun, Totanu...

Rusts are one of the most severe threats to cereal crops because new pathogen races emerge regularly, resulting in infestations that lead to large yield losses. In 1999, a new race of stem rust, Puccinia graminis f. sp. tritici (Pgt TTKSK or Ug99), was discovered in Uganda. Most of the wheat and barley cultivars grown currently worldwide are susceptible to this new race. Pgt TTKSK has already s...

Thomas, J. B., Conner, R. L. and Graf, R. J. 2012. Radiant hard red winter wheat. Can. J. Plant Sci. 92: 169 175. Radiant hard red winter wheat (Triticum aestivum L.) is well adapted to the non-hazard region for stem rust (Puccinia graminis Pers.: Pers. f. sp. tritici Eriks. & E. Henn.) within the Canadian prairies. Based on evaluation relative to Norstar, CDC Osprey, AC Tempest and AC Bellatri...