How does the Tobacco Mosaic Virus spread in plants?

Question

I am doing a research project on the Tobacco Mosaic Virus and I would like to know whether it is by reverse transcrition that the virus spreads through a plant.

Answer 1

Tobacco mosaic virus (TMV) is not a retrovirus, so it does not use reverse transcription. TMV moves from cell to cell in a leaf by setting up replication sites next to or in plasmodesmata. Plasmodesmata are pores through cell walls that connect plant cells to their neighbors. The TMV replicates, and the new RNA moves into the neighbor cell and starts another infection. TMV keeps moving this way until it reaches a vein.

When TMV reaches a vein the viral particles (RNA covered by a protein shell, called a virion) moves into the phloem. Phloem acts as a transporter of sugars and nutrients in plants, and the virus hitchikes along to get to other uninfected leaves. Once in a new leaf, the virus leaves the phloem and starts the cell to cell movement again.

Answer 2

Dear angel, TMV is a nucleo-protein. It is rod shaped. It contains single strand RNA. Dissemination : Usually,viruses enter the plant cells through the wounds either made mechanically or by vectors. In almost all cases, they reach phloem and then are transported within the parts of the plant. The sreading from one plant to another plant occur as follows: 1.through vegetative propagatoin, 2.through sap of the infected plants, 3.through seeds, 4.through pollen, 5.by insect vectors, 6.by mites, nematodes and fungi. Symptoms : 1.Chlorosis : The green tissues of the plant become pale due to thealteration in the normal development of chlorophyll. 2.Mosaic formation : The various degrees of chlorosis result in the formation of yellow and green spots on the leaf which give the appearance of the mosaic., The disease will affect the quality of the tobacco leaves which in turn will affect the yield.