Loebenstein, G., Virus Laboratory, ARO, The Volcani Center, Bet Dagan, Israel
Raccah, B., Virus Laboratory, ARO, The Volcani Center, Bet Dagan, Israel

Transmission of non-persistent viruses, characterized inter alia by acquisition and inoculation of virus during brief probes, absence of a latent period after acquisition, and loss of virus after short feeding periods, has not been reduced satisfactorily by vector control using insecticides. Breeding for resistance is one of the most efficient ways for control, but progress in breeding programs is slow, and resistance depending on one gene only is often overcome by new strains of the virus. Avoidance of infection, and the use of oil sprays, reflective surfaces, yellow sticky traps, white nets and border crops, are reviewed, as possible alternative control approaches. Of these, oil sprays are presently used in practice. The possible mechanisms of the mode of action of oils are discussed. It is expected that these methods, singly or in combination, may become of further importance, especially in highvalue crops such as virus-tested propagation material of flower bulbs and corms. © 1980 Springer Science + Business Media B.V.