ABSTRACT
Plant viruses remain to be elusive and enigmatic causes of several destructive crop diseases defying human efforts to restrict the incidence and spread of diseases induced by them. The usefulness of various diagnostic techniques employed for detection, differentiation and quantification and biology of soil- and waterborne plant viruses is discussed hereunder. Detection of Tomato mosaic virus (ToMV) in ice indicated the possibility that stable human and other viruses might be preserved there, and that entrapped ancient viable viruses might be continually or intermittently released into the present environment. ToMV is one of the several soilborne plant viruses that spread under natural conditions without any known biotic vector. Different types of immunoassays have been applied for the detection, identification and quantification of plant viruses in plants, seeds, propagules, and alternative sources of infection such as weeds, soil, water and other environmental samples. Nematodes are involved in the transmission of plant viruses, in addition to their ability to induce different diseases.
