INCIDENCE OF STEM FITTING OF LOVELL ROOTSTOCK AND OWN-ROOTED REDHAVENAND CRESTHAVEN PEACH-TREES

Own-rooted 'Redhaven' and 'Cresthaven' peach [Prunus persica (L.) Bats ch.] trees and 'Redhaven' and 'Cresthaven' on Lovell seedling rootstoc k were planted in fumigated acid nonfumigated areas of a site where pe ach trees previously displayed peach stem-pitting (PSP) symptoms. The combined incidence of stem pitting of the 'Redhaven' and 'Cresthaven' peach trees was 16% on nonfumigated soil in the Ip years of the study. The combined stem-pitting incidence of own-rooted trees (9.1%) was si gnificantly lower than on Lovell roots (22.1%). Incidence of PSP in th e adjacent fumigated areas was relatively low (1% Lovell and 4% own-ro oted) and, therefore, precluded a comparison of own-rooted and Lovell- rooted trees. Within affected sections of rows, 67% of the 'Cresthaven '/Lovell and 64% of the 'Redhaven'/Lovell trees had PSP symptoms, but only 25% of own-rooted 'Cresthaven' and 18.8% of own-rooted 'Redhaven' trees were symptomatic. Although these data suggest that rooted cutti ngs of these cultivars may be less susceptible to stem pitting, the us e of rooted cuttings does not eliminate fumigation as a means of provi ding acceptable stem-pitting management in a heavily infested site.