Co-Authors:
Globerson, D., Division of Field Crops, Agricultural Research Organisation, The Volcani Center, Bet Dagan, Israel
Netzer, D., Division of Plant Pathology, Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel
Tjallingii, F., Institute of Phytopathological Research (IPO), Wageningen, Netherlands
Abstract:
Fifty-eight lettuce cultivars were tested for their reaction to three races of downy mildew in Israel and to four races in the Netherlands. It was found that in these two countries at least seven different races exist. The inheritance of resistance to each race was established. The resistance to each of six races (IL-2, IL-3, IL-4, NL-1, NL-3 and NL-4) is controlled by one dominant gene; only to race NL-2, control is by two dominant complementary genes. From the reaction of the various cultivars and their progeny, a genetic designation for host-parasite relationship is suggested. © 1974 H. Veenman En Zonen B.V.