The Agriculture and Horticulture Development Board (AHDB) has issued a ‘yellow rust watch list’ to help flag UK winter wheat varieties most likely to perform out of line with the disease ratings published in its Recommended Lists.

The watch list orders varieties based on yellow rust levels from the three worst Recommended List trials for each variety, in order to help identify those 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 Recommended List 2021-2022 in December.

Discussions on the latest twists and turns in the yellow rust story will also feature as part of the UK Cereal Pathogen Virulence Survey (UKCPVS) stakeholder meeting, which takes place online on March 12, 2021.

Catherine Harries, who manages disease research at AHDB, said: “The online wheat yellow rust watch list 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.

“Following the introduction of the new rating calculation approach, it is good to see that the watch list shows that varieties are performing broadly in line with the Recommended List ratings.

“However, as the situation can change rapidly, it is important to monitor all crops closely and report unexpected levels of disease to the UKCPVS.”

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.

Targeted at breeders, crop scientists and technical agronomists, the annual stakeholder meeting reports on results from recent National Institute of Agricultural Botany (NIAB) led screens.

This year, the event also includes two presentations on the management of cereal rusts in the field.

AHDB plans to update the watch list – which features all recommended winter wheat varieties – annually, following the release of the latest Recommended List.

The current watch list uses trial data from the 2019-2020 season. Ratings are based on a three-year data set. The Recommended List 2021/22 booklet edition is now available.