A plant species requiring two taxonomically different hosts to complete its entire life cycle. The rust fungi, such as White Pine Blister Rust, are classic examples.
Requiring more than one host species to complete a life cycle (e.g., of Uredinales) ( 15)
A heteroecious parasite is one that requires at least two hosts. The primary host is the host in which the parasite spends its adult life; the other is the secondary host.