Following the recent release of the 2013 stripe rust report, the Global Rust Reference Center in Denmark has now just published the latest report detailing the results of race analysis for Puccinia striifromis samples submitted during the period January – December 2014. A total of 250 yellow rust infected leaf samples from 12 countries entered the recovery process using susceptible seedlings of Cartago and Morocco. A total of 83 isolates were recovered and multiplied whereas 5 isolates from Pakistan were avirulent on both Cartago and Morocco. A subset of 52 isolates from 2014 and 10 additional isolates collected in 2013 were pathotyped using an extended set of wheat differential lines carrying resistance genes to P. striiformis.
Key highlights from the report are:
- Races of the aggressive strain (likely PstS2) were common across many sampling areas in East Africa and Asia
- Aggressive strain PstS2 was detected frequently in Ethiopia, Kenya, Tanzania and Rwanda, often with additional virulence to Yr1 or Yr10
- Another group of Yr27-virulent races were observed in East Africa, e.g., Rwanda and Ethiopia
- The races in Central Asia often combined multiple virulences and many isolates produced huge amounts of telia, which may suggest a recent evolutionary origin from a sexual population
- ‘Warrior’ race was detected in Morocco and Algeria (exhibits same characteristics as above)
- Very similar races to ‘Warrior’ have been observed in Bhutan (2012) and in 2014 also in Nepal. However, these Warrior-like races from South Asia differed from the Warrior race in Europe by DNA markers and in response to additional, non-standard differentials.
A copy of the report – Hovmøller & Rodriguez-Algaba 2015: Global Rust Reference Center: Research funded by: Aarhus University,Denmark; CIMMYT; ICARDA – can be found on Wheatrust.org