SUSCEPTIBILITY TO PEACH LEAF CURL (TAPHRINA DEFORMANS BERK.) TUL. IN A PEACH GERMPLASM COLLECTION

The susceptibility of 1103 peach genotypes (738 dessert peach, 168 cli ngstone, 197 nectarines) and 152 unselected seedlings to leaf curl (Ta phrina deformans) was assessed. No cultivars rated zero, which is equi valent to immunity, only six rated 1, while 62% had the highest suscep tibility rating 5. Presence or absence of leaf glands and fruit type w ere not correlated to resistance or susceptibility. The distribution o f the different fruit type and the unselected seedlings over the vario us susceptibility categories indicates a loss of resistance to leaf cu rl during selection for improved agronomic characters.