Trials of Italian Pines for susceptibility to Melampsora pinitorqua Rostr.1

The susceptibility of different pine species of Italian origins to Melampsora pinitorqua was determined in natural and artificial environments on seedlings, varying in age from 1–2 months and older. Seedlings differed significantly in their susceptibility depending on species and age. Decreasing degrees of infection and varying localization of infections according to the stage of development were observed in the very young seedlings of Pinus pinea.