Incidence of virus diseases in trials to grow foundation-stock seed potatoes in Israel

Sampling of aphids in the Galilee mountains indicated a remarkable ebb in the numbers of alateMyzus persicae individuals during the hottest summer months of June–September. This apparen seasonal lack of vectors was reflected in the results of a preliminary field trial carried out there in the summer of 1966, whereby hardly any aphid transmission of potato virus Y (PVY) could be noticed.