Susnoschi, M., Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Krikun, J., Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Zuta, Z., Hazera Seed Co., Israel

Experiments were conducted to investigate the relative susceptibility to Verticillium wilt of common potato varieties (not bred for resistance) grown under arid zone conditions. The response of varieties grown in infested plots was compared with that of varieties grown in non-infested plots serving as control. The reductions in growth period and yield were considered as criteria in determining the degree of susceptibility to the pathogen. The cvs. Désirée, Alpha and Baraka were found to be tolerant to the fungus. In comparison with control plants, these cultivars showed no reduction in growth period and only limited yield losses, despite high levels of stem and tuber infection. Their field resistance is related to their strong haulm development and lateness of maturity. © 1976 Kluwer Academic Publishers.