It was confirmed that in the north of Poland winged specimens of Myzus persicae (Sulz.) start to migrate in spring approximately over three weeks later than in the central and sou them regions. It was observed that during the 1981-1990 and 1991-2000 decades, M. persicae started its flights approximately over two weeks earlier than during the 1971-1980 decade. With this respect one may conclude that the changes are permanent. There were also changes in quantity. In some places the M. persicae share in the entire aphid fauna on potato crops was observed to have decreased as the time passed, which, as it seems, may be associated with a decrease in potato crops area in Poland. Such a correlation can also be confirmed by the fact that in the area where M. persicae share increased, the potato crops area also increased extensively.

Monitoring of aphids - vector of potato diseases virus - continued in Poland for 30 years in 5 localities, indicated some changes in pressure exerted by these insectes. The biggest differences were observed for Macrosiphum euphorbiae (Thom.) and subsequently for Aphis frangulae Kalt. and Aulacorthum so/ani Kalt. Reduction in population of these aphids has been observed according to elapsing time in all five localities. In case of Myzus persicae (Sulz.) or Aphis nasturtii Kalt., these changes involved decrease or increase of the pressure, depending on the locality.