Out of Uganda: An Aggressive Crop Killer That Threatens Global Food Fungal disease in wheat crops has been a serious but controllable problem, but a newer strain of what’s called “stem rust” has scientists worried. January 8, 2018 by Kerstin … Continue reading
Search Results for: "South Africa"
Wheat is a minor crop in Malawi, however the geographical location situated between the wheat growing countries of East Africa and Southern Africa raises the question whether it acts as stepping stone for the movement of wheat rusts, especially stem … Continue reading
New molecular diagnostic assays are providing rapid and useful information on the Ug99 race group in Africa. The assays have been developed by the group led by Dr Les Szabo at the USDA-ARS Cereals Disease Laboratory in St Paul, Minnesota, … Continue reading
Effective / Ineffective stem rust Resistance Genes The following table summarizes the effective and ineffective stem rust resistance genes for races in the Ug99 lineage (based on Singh et al., 2006). TTKSK (Ug99) TTKSF TTKST (Ug99 + Sr24) TTTSK (Ug99 … Continue reading
Several different systems exist for race nomenclature of stem rust and there is no single standard unified system. This meets the need of individual countries, but makes international comparison a difficult task. In a recent international survey of rust labs … Continue reading
Differential sets are a vital component of race analysis. The aim is to have a set of differential varieties, ideally each with a different single resistance gene, which can distinguish races by their qualitative differences in reactions to different pathogen … Continue reading
Status Summary: Ug99 Lineage – September 2021 Race TTKSK (Ug99) was the first known race of P. graminis f. sp. tritici with virulence to the stem rust resistance gene Sr31. It also possesses virulence to a wide range of resistance … Continue reading
Survey updates – Southern Africa Mozambique: Wheat rust surveys were undertaken by IIAM, Mozambique and FAO in the key wheat growing areas of Manica and Tete provinces, Central Mozambique during the period 26th August – 1st September 2010. Wheat in … Continue reading
stem rust samples collected near Harare in Sept 2009 have been confirmed as race TTKSF, the presumed progenitor of Ug99. Analysis undertaken by the University of the Free State, South Africa and the USDA-ARS, Cereals Disease Lab, Minnesota, USA confirmed … Continue reading
Unusual and severe epidemics of yellow rust were observed on several continents in 2017. In a number of cases, epidemic sites at different continents were inter-related by prevalence of genetically identical yellow rust genotypes and races. Key highlights South America: … Continue reading