Transmission and movement of plant viruses

Abstract

Plant viruses are obligate parasites and their survival depend on being able to spread from one susceptible organism to another. Viruses cannot penetrate the intact plant cuticle and the cellulose cell wall. Therefore penetration is made trough wounds in the surface layers, such as in mechanical inoculation and transmission by vectors. There is specificity in the mechanism by which the plant viruses are naturally transmitted. They are important economically only if they can spread from plant to plant rapidly. They are contagious agents that differ in their transmissibility. No transmission of virus occurred when the virus titer in the inoculum was too low and there is no susceptibility between virus, vector, and host. Also the presence of some substances in the inoculum, which inhibited the infection process, hampered the transmission of viruses. Knowledge of the ways in which plant viruses spread is essential for the development of control measures.