WORRYING LEVELS of Septoria have been found in winter wheat crops, growers have been warned.
High temperatures and a poor contribution from T1 sprays are to blame, according to the latest Crop Monitor national report.
“The presence of symptoms on leaf 2 so soon after flag-leaf sprays were applied has alarmed some people,” according to ADAS pathologist Bill Clark.
“This is a clear indication that the gap between the T1 spray and the flag-leaf spray was too long – resulting in the tip of leaf two becoming infected.”
Mildew continues to develop, but damage at this stage of the season can easily be over-estimated, advises Mr Clark.
The risk from fusarium ear blight could be high, warns the report, with high temperatures favouring the disease.
But the primary role of the ear wash spray will be to top up the fungicide on the flag leaf and leaf two, particularly in high-risk septoria varieties.
Ear wash sprays are now being applied on and around the Cereals 2004 site in Lincolnshire, according to the Independent Crop Consultants‘ local report.
“Crops on lighter land are stressing out due to dry weather and second wheat is showing take-all symptoms,” notes the report.
In the South East the AICC report notes no further treatment are planned where the T2 spray went on after ear emergence, apart from seed crops.
“Crops which did not get a T1 spray until after May 12 now have 30% of leaf three and 15% leaf two carrying septoria,” according to the Suffolk AICC report.
But in the south agronomists report that Septoria remains confined to lower leaves, with all T2 sprays applied in good time.
Leaf tipping is showing, particularly on Consort and Claire, in Shropshire and West Staffordshire.
CropMonitor will be featured at the Central Science Laboratory stand at Cereals 2004, where visitors can see the demonstration plots that are monitored as part of service.
Crop Monitor is a new, free service that uses live data from trial sites across the UK along with historical data to give growers an accurate picture of disease development in wheat and oilseed rape .
Funded by the Department for the Environment, Food and Rural Affairs and run by Central Science Laboratory, weekly updates are provided by ADAS pathologists and AICC agronomists.
The Crop Monitor website allows users to view data in graphs by region, variety, cultivar, leaf number or a combination of their choice.
The site also provides access to historical data from DEFRA-funded research and showcases new research developments.
CSL stand no at Cereals 2004: 506