Changes Induced by Magnesium Ions in the Morphology of Some Plant Viruses with Filamentous Particles

Abstract

SUMMARY Particles of henbane mosaic virus in extracted plant sap were usually straight and 900 nm. long but occasionally flexuous and 800 nm. long. The length and flexuousness of the particles depended on the composition of the extracting medium. When exposed to magnesium ions (0.05 m), the particles were long and straight but when exposed to 0.05 m-EDTA they were shorter and flexuous. Similar morphological differences were found when pepper veinal mottle virus or bean yellow mosaic virus was extracted in the two solutions. With pepper veinal mottle virus, each form of particle could be converted to the other by changing the medium.