Aphid monitoring in seed potatoes has now ended for 2017 so this will be the final report.
Only one sample, from the Midlands, was received in the last week and this did not contain any aphids.
The total number of samples received for the year to date is 794.
Thank you all for participating in the aphid monitoring scheme this year. It wouldn't be possible without you all sending samples every week. I hope you have found it useful and that you will take part again next year. We'll be in touch in Spring.
I would very much appreciate any feedback you have about the scheme, both in it's usefulness and if there are any improvements you would like to see to any aspect of it.
Along with the results from your aphid trap you need to take into account the following
factors when considering the risk of virus spread.
Mature plant resistance. Crops are generally at their most vulnerable
within the first four weeks from emergence. After this time 'Mature Plant Resistance'
builds up which makes it more difficult to transmit virus within the crop. The crop is
again more vulnerable to virus spread if there is regrowth after dessication.
Cultivar resistance. Different varieties of seed will have different
inherent natural resistance to PVY. Using a more resistant cultivar will reduce the
risk of virus transmission.
Volunteers and seed quality. In most situations it is unlikely that
aphids will bring PVY into your crop (see next note). The greatest risk is from aphids
spreading what little virus may already be present. This can come from two possible
sources. Volunteers from previous potato crops and low levels of virus in the seed
Surrounding crops. The risk of aphids spreading PVY to your crop
from elsewhere is increased when ware crops are grown close to your seed. This is
because there will be greater numbers of aphids and ware crops generally have a
higher incidence of virus present.