Be sure to test home-saved seed potatoes before planting, warns NIAB. High levels of Potato Virus Y have been found in checks on tuber samples sent to its Cambridge laboratory.
Over a quarter had more than 10% PYV infection and, more worryingly, said pathologist David Kenyon, 14% had over 50% infection which in non-tolerant varieties could lead to “drastic” yield loss.
PVY infection is the main worry for farmers wanting to plant home-saved seed tubers next season, said Dr Kenyon.
Most of the heavy infections have been in samples of Estima, which is PVY-tolerant. But growers should remember that planting such tubers can provide hot spots of infection which can easily be spread to nearby more susceptible varieties by aphids, he pointed out.
“On a more positive note Potato Leaf-Roll Virus has only been found at very low levels in the majority of samples with less than 1% of samples being rejected this year.”
Of the mild mosaic viruses (PVA, PVS, PVV and PVX) Potato Virus A has been the only virus causing concern to date.
“This level of PVY makes it imperative that farmers act now to ensure their farm-saved tubers are free of infection. We have pulled out all the stops to ensure our laboratories in Cambridge offer a prompt test turnaround as well as back-up advice to farmers.”
The test costs £105/sample. A visual check and eye-plug test for fungal diseases costs an extra £35.
For details tel 01223 342204 or email: firstname.lastname@example.org