The Aphid Monitoring Programme was introduced into the Seed Potato Classification Scheme in 1992. The aim of the programme is to identify seed crops on which aphids have been poorly controlled and which consequently have a higher than normal risk of being infected by virus.  Before such crops can be accepted for classification, a representative sample of tubers is subject to a post-harvest tuber test for the presence of viruses. Only if this test result is satisfactory is the stock accepted. Following the outbreak of aphicide resistant Peach-Potato aphids in 2001, the procedures involved in the aphid monitoring programme were revised in 2002 by removing the issuing of aphid alerts for areas to empower growers to make decisions on aphicide applications based on local intelligence.  Ultimately this approach might encourage a reduction in the extent of prophylactic application of insecticides. 

Inspection of the 2008 Scottish seed potato crop revealed a slight decrease in the number of crops containing virus affected plants, to a total of just below 14% of the total area entered for classification.  The incidence of severe mosaic symptoms fell from 1.7% in 2006 to 0.9% and mild mosaic symptoms decreased from 12.6% to 9.6%.  The incidence of crops containing any leafroll increased from 1.6% to 3.4%.  Recent evidence collected at SASA indicates that cereal aphids may have an important role in transmitting PVY, the prevalent cause of mosaics.  As the two species of cereal aphids most closely linked with PVY transmission were moderately abundant during 2008, the incidence of mosaics in 2009 should be similar to that observed in 2008.

Following average winter temperatures, forecasts indicate that the first suction trap catches of M. persicae in 2009 will occur in mid-June and there should be minimal potential for populations to build up to relatively high levels during the period of crop growth.  Levels of leafroll did increase in 2008 and should remain at around 3.4%, or decline slightly, in 2009.