Electron microscopy of mycoplasma-like bodies associated with insect and plant hosts of peach Western X-disease

Abstract

Preparations of the leafhopper, Colladonus montanus (Van Duzee) and celery, Apium graveolens L., were examined in the electron microscope. Mycoplasma-like bodies ranging from 200 to 400 nm in diameter were found in the tissues of leafhoppers and in the phloem cells of celery infected with Western X-disease. The Western X mycoplasma-like bodies (WXM) were found in the intestine of the leafhopper 19 days after acquisition feeding on diseased celery, and in the brain 20 days after injection with diseased leafhopper extract; WXM were also found in the phloem cells of celery 20 days after inoculation. Large, electron transparent bodies, either spherical or pleomorphic in form, and small, electron transparent bodies of WXM were commonly observed during the early stages of WXM multiplication, whereas the spherical dense bodies of WXM were observed at the later stage of multiplication. A second mycoplasma-like body, apparently unrelated to Western X-disease, was found in both healthy and diseased leafhoppers, but never in celery.