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Photo: Erling Fløistad
Healthy seed potatoes combat Potato virus Y
Potato virus Y (PVY) is a major challenge for Norwegian potato cultivation. The virus can
halve yields if it spreads uncontrolled.
At Reddal Fellespakkeri in Grimstad, 13 producers
collaborate on packing and selling early potatoes.
Around 2007, they encountered serious problems
with PVY in the Juno variety. The potatoes grew
poorly and split, and it took a long time to identify
the cause.
“Today we send all samples of seed potatoes to
NIBIO for virus testing, and it makes an enormous
difference. If you start with virus-free seed potatoes,
you avoid major losses,” says Knut Salve Lunden,
managing director of the packing facility.
“Ideally, we don’t use seed potatoes with more than
2–3 per cent infection, and 10 per cent is an absolute
limit. I don’t understand how anyone dares not to
test. The risk is high, and the consequences can ruin
the entire crop,” says Lunden.
Seed potato quality is crucial when it comes to potato
viruses. PVY is transmitted by aphids. If a field has
some virus initially, aphids can spread it so that
infection increases from 2 to 20 per cent during a
season. In cool summers, spread is limited, while in
warm summers the infection pressure rises rapidly.
Early varieties such as Juno are particularly sensitive
to PVY. When Juno develops excessive splitting, the
potatoes end up as waste, causing economic losses
for the farmer. The Asterix variety may be infected
without showing obvious symptoms yet still act as a
source of infection. If PVY spreads freely, yield losses
can be substantial (40–70 per cent), in addition to
quality problems.
Purpose: The Plant Clinic at NIBIO offers winter testing of seed potatoes for all potato producers in Norway to
prevent uncontrolled virus spread when using home-grown seed potatoes.
Collaboration: Norwegian Agricultural Advisory Service
Contact: Research Professor Dag-Ragnar Blystad, Division of Biotechnology and Plant Health.
Email: dag-ragnar.blystad@nibio.no | Telephone: +47 908 72 588.
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