Mechanical Sap Transmission

Abstract

The transmission of a virus from infected to healthy plant is an important procedure to study the biological properties of the virus. Mechanical transmission is an in vitro method of virus transmission used for a variety of assays such as isolation and propagation of virus isolates, establishing pure culture and sub-culturing of virus isolates, assay for virus infectivity, diagnosis of the virus through indicator hosts, determination of host range and properties of the virus in crude sap and so on. In the laboratory, this is usually accomplished by grinding the leaf of a diseased plant, and rubbing the infectious sap on to the leaf of a healthy plant. The procedure is referred to as mechanical or sap transmission. The different steps and requirements for the process of mechanical transmission are discussed in the chapter.