Maintenance In Vitro of the Aster Yellows Mycoplasmalike Organism

Abstract

Longevity in vitro of the aster yellows mycoplasma-like organism (AYO) isolated from the leafhopper vector, Macrosteles fascifrons, was determined by an infectivity assay after incubatin in isolation media in which the factors of pH and osmolarity were varied. Longest in vitro survival, up to 72 h, occurred at a neutral to slightly alkaline pH (pH 7.0-7.5) and high osmolarity (800-1000 mOs/kg). At pH greater than 7.5, at any osmolarity tested, survival of the AYO was minimal. The addition of spermine (10 .mu.g/ml) appeared to enhance maintenance at suboptimal osmolarity.