Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Plants, Soils, and Climate

Committee Chair(s)

H. Loran Blood


H. Loran Blood


Collections of tomato mosaic virus obtained from Utah and California produce a localized severe leaf and stem necrosis on dature meteloides. After the streaked plant has stood sufficiently long to permit secondary growth to occur, a systemic diseased expression develops in a few of the plants. No reference to a similar development on Dature meteloides following inoculation with the tobacco mosaic virus was found in the literature. The tomato mosaic virus is thought to be the same as the Johnson's tobacco mosaic virus No. 1. The virus obtained from the tissue of Dature meteloides exhibiting the systemic infection produces symptoms which cannot be distinguished from the symptoms of the Utah tomato mosaic or the tobacco mosaic virus No.1 on the tomato. This same virus can be transferred through several generations of tomato and back to Dature meteloides without loosing its identity. These observations led to the questions: Is the tomato mosaic virus the same as the tobacco mosaic virus? Does the tomato mosaic virus change on dature meteloides to produce the systemic virus or is the systemic virus one of a complex of viruses existing on the tomato in the West? Is the systemic virus a modified form of the tomato mosaic virus?