Agronomists are urging growers to catch light leaf spot early to prevent reductions in yield of up to 0.7t/ha to 1.5t/ha if left unchecked.
Technical manager at Agrovista Mark Hemmant also reiterated the need for farmers across the country to be on alert, with the latest Crop Monitor again showing the problems not just being consolidated to the north.
“There are many growers who won’t have been able to get an autumn application on so as soon as you see it go and spray if conditions allow. The positive about this season is that you will be able to hit phoma at the same time so applications of prothioconazole and flusilazole will target both.
“The most important thing in this high risk year is timing, with light leaf spot offering little flexibility to the grower if you get it wrong and don’t take control,” he said.
The treatments for light leaf spot are preventative not curative, highlighting the need to catch it early.
Those who have been able to get an autumn application on will still need to monitor their crops carefully for both phoma and light leaf spot particularly on small oilseed rape crops. While growers choosing Proline (prothioconazole) must remember it cannot be mixed with Crawler (carbetamide).
Mr Hemmant also highlighted the need for farmers to keep an eye out for slugs in struggling crops .
“Unfortunately for these crops, slugs are still a problem, so growers need to keep on top of them because even small plant populations can still make a good crop. Hopefully, with some cold weather looking likely we can overcome this problem. Pigeons will also need to be kept on top of as they are again still causing problems,” he added.
Get advice on OSR canopy management in our latest High 5 OSR Challengearticle.