The biology and taxonomy of rust fungi associated with the neotropical vine Mikania micrantha, a major invasive weed in Asia

摘要

Three microcyclic rust species were collected during surveys of the perennial asteraceous vine Mikania micrantha (Eupatorieae: Asteraceae) throughout its native range in the Neotropics but were absent in its invasive range in Asia. The commonest species, Puccinia spegazzinii with brown te-lioid telia, occurred wherever M. micrantha was found in South and Central America including the Caribbean island of Trinidad. Dietelia portoricensis, with occasional vestigial spermogonia and grayish-white to paleyellow columnar aecioid telia, was collected only in Costa Rica; while D. mesoamericana sp. nov., apparently restricted to Mesoamerica, can be distinguished by its abundant, yellowish-orange, fertile spermogonia, yellow to pale brown telial columns, larger teliospores, and 4-spored rather than 2-spored metabasidia. The fact that all three species share a fundamentally similar symptomatology suggests a common origin.