Axenic Culture of a Plant Pathogenic Spiroplasma

Abstract

EVIDENCE has accumulated that a number of insect-transmitted plant diseases of the “yellows” group result from the infection of plants by organisms resembling mycoplasmas^1–2. Circumstantial evidence suggests that two such diseases, corn stunt and citrus stubborn, may be caused by a novel type of helical prokaryotic microorganism lacking a cell wall, for which the trivial name “spiroplasma” has been proposed³. The agent of corn stunt has so far defied attempts at culture in a cell-free medium and although an organism associated with citrus stubborn disease has been successfully cultured from diseased plants^4,5 it has not, to our knowledge, been shown to be a plant pathogen.