FLAG LEAF is emerging in many forward wheat crops and farmers are being urged to get spraying programmes up to date.
The timing alert has been issued by Crop Monitor , a new government-funded web-based service which monitors disease in live trial sites across the UK and provides regular updates for growers.
The recent rainfall and warm weather has sparked a growth surge in many crops across the UK, according to the latest national report compiled by ADAS pathologist Bill Clark.
A delay in applying T1 sprays means emerging leaves should still have good disease protection, he notes.
“But this delay will have resulted in little or no control of Septoria on leaves 3 and 4.”
Rain splash could put leaf 2 and flag leaves at risk of infection, so growers may want to think twice about extending even a short gap between the T1 and T2 sprays, he advises.
The good news is that the rapid growth has “generally left mildew behind”.
But this is not the experience of some independent agronomists providing Crop Monitor‘s regional reports.
“Mildew is still apparent on Solstice, Chatsworth, Claire and Einstein to some extent,” according to the latest AICC Lincolnshire report .
“Option and Malacca continue to develop faster than many other varieties,” note agronomists in Norfolk and Cambridgeshire, who recommend that Opus (epoxiconazole) rates should be raised.
But wet conditions have hampered field work in Kent and East Sussex, where some crops have not yet received T1 nitrogen dressings.
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.