Production of the nutritional requirements for growth of Cronartium ribicola by a nonhost species

Abstract

Tissue cultures derived from the cortex of Pseudotsuga menziesii provided the nutrients required to support growth of Cronartium ribicola, a rust fungus. In nature, this obligate parasite is sustained by Pinus and Ribes spp. only. The pathogen was separated from its source of nutrients by a cellulose membrane. These experiments demonstrated that the nutritional factors required for growth of this rust are not host-specific and have small molecular size.