- Rust Issues: Yellow rust is the most serious constraint to wheat production, but leaf rust is also a problem. Stem rust is detected annually but is not economically damaging.
- Ug99 Status: No Ug99 lineage races have been detected in Turkey.
Following the confirmed detection of Ug99 (race TTKSK) in Egypt in 2014 (BGRI special newsletter report April 2015) increased vigilance is needed for stem rust in the eastern Mediterranean. Although no confirmed reports of race TTKSK have been obtained from Egypt in 2015, trace amounts of stem rust (race unknown) were detected in the central delta of Egypt in early March 2015. No further reports of stem rust outbreaks have been reported from Egypt in 2015. Crops in Egypt are now approaching maturity, with harvesting occurring between mid April to mid May. However, if any stem rust inoculum were to build up in Egypt then spore deposition models run jointly by the UK Met Office and Cambridge University indicate that there is a risk of onward movement of spores to the eastern Mediterranean basin. Model results show consistent seasonal deposition patterns over the last 12 years, indicating a higher risk, relative to other areas, of spore deposition for Israel, Lebanon, Jordan, eastern Syria and southern Turkey. During the months April and May typically there is a large spatial variation of deposition patterns, with long-distance dispersal of spores that reach eastern Mediterranean countries (see Fig 1 – Data from March, April, May 2014 used as an illustrative example of typical spore dispersal patterns). The most recent spore deposition forecast maps for the period 8 – 14 April 2015, based on confirmed sites for Ug99 (race TTKSK) in Egypt in 2014 agree well with the long-term dispersal trends. Increased surveillance and monitoring is advised in Israel, Lebanon, Jordan, eastern Syria and southern Turkey. Sampling of any stem rust detected in the eastern Mediterranean and rapid race identity confirmation is recommended (either by race analysis on live samples or through the USDA CDL SNP assay for the Ug99 race group). Please contact Dave Hodson, CIMMYT (email@example.com) for more details on sampling options.
A new study entitled “Determination of Puccinia graminis f. sp. tritici races of wheat in Turkey” has been published in the Turkish Journal of Agriculture and Forestry. Dr Zafer Mert from the Central Research Institute for Field Crops (CRIFC), Ankara led the study. Extensive surveys throughout the wheat growing regions of Turkey were undertaken in 2007 & 2008. From these surveys a total of 40 stem rust isolates were obtained and race analysis, using the North American 20 genotype differential set, was carried out. A total of 21 different stem races were identified over the 2 year period. Race TKTTC was the most common race identified. Unpublished studies by Dr Mert and the CRIFC research group have revealed the continued predominance of race TKTTC in Turkey in 2011 & 2012. The study indicates that pathogenic variation of Pgt in Turkey is high and the common occurrence of Berberis spp. was noted by the authors, although no direct evidence for a functional role was demonstrated in the current study. No Ug99 race group members were detected in the study. Resistance genes; Sr24, Sr26, Sr27 and Sr31 were all found to be effective against all Pgt races present in Turkey.