A yellow rust watchlist has been issued to help identify winter wheat varieties most likely to perform out of line with office disease ratings.
The watchlist orders varieties based on yellow rust levels from the three worst Recommended List trials for each variety. The Agriculture and Horticulture Development Board says it can help identify those varieties most likely to benefit from closer monitoring.
It follows the development of a new rating calculation approach that better reflects the diverse and dynamic nature of the UK’s rust populations, announced at the launch of the online edition of the 2021/22 Recommended List in December.
Discussions on the latest twists and turns in the yellow rust story will feature as part of the UK Cereal Pathogen Virulence Survey (UKCPVS) stakeholder meeting, which takes place online on 12 March 2021.
AHDB disease research manager Catherine Harries said: “The online wheat yellow rust watchlist provides a way to flag unusual levels of yellow rust seen in some varieties in some trials, compared with what the headline disease rating would otherwise suggest.
“This extra layer of information can provide a valuable early warning of a potential change in the UK’s race structure and help focus in-season management strategies.”
The watchlist showed that varieties are performing broadly in line with the Recommended List ratings, said Ms Harries. But as the situation can change rapidly, it is important to monitor all crops closely and report unexpected levels of disease to the UKCPVS.”
The UKCPVS was set up to detect and warn the industry about new races of rusts and mildew that are capable of causing disease on previously resistant cereal varieties. It is targeted at breeders, crop scientists and technical agronomists – as well as farmers.
The current watchlist uses trial data from the 2019/20 season. Ratings are based on a three-year data set. To access the watchlist, visit ahdb.org.uk/rl