Risultati di un triennio di prove per verificare la suscettibilità di alcune selezioni di pero al fitoplasma della moria.

Several pear cultivars mainly grafted on OHxF 40 were inoculated with pear decline infected materials to verify their susceptibility to the disease. Cultivars /selections employed were: 80-57-83 (Bohème) 80-104-72 (Aida), Turandot, Tosca, Norma, Harrow Sweet, and Carmen. The pathogen inoculation was performed with symptomatic and/or PCR positive pear tissues at the end of the summer. Control to verify symptom and phytoplasma presence were performed at the end of the summer of the year after inoculation. Nested PCR tests allow the identification of pear decline phytoplasmas in both symptomatic and asymptomatic inoculated plants. Harrow Sweet was the cultivar most susceptible to pear decline phytoplasmas since it was PCR positive in both the experiments where it was present, and moreover at least one plant per experiment was also symptomatic. Selection Norma grafted on BA29 was the only one asymptomatic and negative to molecular tests, however the same selection when grafted on OHxF 40 severl plants resulted PCR positive and symptomatic. Selection Tosca grafted on the latter rootstock was always negative to molecular analyses and selection Aida, although positive to molecular tests did not show symptoms.