INTERACTION BETWEEN SYNCHYTRIUM-ENDOBIOTICUM (SCHILB) PERC AND COLLETOTRICHUM-COCCODES (WALLR) HUGHES IN WART RESISTANCE TESTING

Resistance screens against wart disease were sometimes confounded by severe necrosis of the material used as the wart inoculum. The cause was latent penetration of the sprouts by Colletotrichum coccodes (C. c.), which only became manifest as a necrosis of the proliferating shoots after infection with Synchytrium endobioticum. In 1985, C. c. was found on 75 % of tubers (Table 1). There was usually less penetration of sprouts at the rose end than those at the middle- or heel-end, but during storage the pathogen grew towards the rose end and the differences disappeared (Table 2). The interaction between Synchytrium and Colletotrichum is discussed.