Cytopathology of maize chlorotic mottle virus in Zea mays L.

Maize plants infected by maize chlorotic mottle virus (MCMV) were observed by electron microscopy to contain viroplasms in xylem and parenchyma leaf c ells. Viroplasms often occluded the lumen of xylem vessels, and were freque ntly associated with highly disorganized chloroplasts in infected leaf cell s. Mixed infections of MCMV and a strain of sugarcane mosaic potyvirus (SCM V-MDB) in maize plants, resulted in the expression of corn lethal ne crosis . Maize plants affected by corn lethal necrosis, contained both MCMV-like p articles and the characteristic cylindrical inclusions induced by SCMV-MDB, in the cytoplasm of infected leaf cells.