“…The molecular genetic advantages of Arabidopsis (RBdei, 1975;Meyerowitz, 1987Meyerowitz, , 1989 have been recently exploited to investigate the genetic control of plant-pathogen interactions (Susnova and Poljak, 1975;Melcher, 1989;Slusarenko, 1990a, 1990b;Li and Simon, 1990;Simpson and Johnson, 1990;Ausubel et al, 1991;Bent et al, 1991;Dangl et al, 1991Dangl et al, , 1992Daniels et al, 1991;Davis et al, 1991;Debener et al, 1991;Dong et al, 1991;Simons et al, 1991;Tsuji et al, 1991;Whalen et al, 1991;Uknes et al, 1992; reviewed by Dangl, 1992b). Two approaches have been taken.…”