Electronic Analysis of Nonpersistent Transmission

In this section, we will review the existing literature on electrically recorded aphid-probing activities and address crucial questions related to the process of nonpersistent virus transmission in an effort to better explain and understand the peculiar and unique properties of these viruses. These exclusive properties of nonpersistently transmitted viruses are difficult to understand and a satisfactory explanation for all of them has not yet been formulated. However, electrical monitoring of...

The Virus

Members of the genus Caulimovirus are DNA viruses with a pregenomic RNA template for replication via reverse transcription. This genus belongs to the pararetroviruses, a supergroup including caulimo-, badna- and hepadnaviruses. This supergroup is a paraphyletic taxon thought to be phylogenetically close to retroviruses. The two most important differences between retro- and pararetroviruses are that (1) the transmissible virus particles of the latter contain double-stranded DNA, whereas those of...

Role of Coat Protein in Potyvirus Transmission

Structure of Potyvirus Coat Protein As indicated above, in many potyviruses loss of transmissibility has been attributed to the coat protein 36 , The potyviral genome is coated with nearly 2,000 subunits of coat protein. Sequence comparison and particle assembly properties suggest the presence of three regions in the CP molecule a surface-exposed N-terminus (varying in length and sequence), a highly conserved core with 215-227 amino acids, and a surface-exposed C-terminus with 18-20 amino...

Groups of Eriophyid Mite Associated Diseases

Diseases Caused or Possibly Caused by Rymoviruses Eriophyid mite-associated diseases can be divided into three groups. As shown in Table I, the largest group of eriophyid mite-borne plant pathogens that have been confirmed to be viruses contains 10 viruses that infect monocots, including well-characterized viruses such as wheat streak mosaic 16-18 , agropyron mosaic 19-21 , and ryegrass mosaic 22, 23 , The viruses all have flexuous rod-shaped particles measuring about 700 nm in length, and...

References

The classification of plant viruses. Wisconsin Agricultural Experiment Station Research Bulletin No. 76. 2. Doolittle, S.P., and Walker, M.N. (1928). Aphis transmission of cucumber mosaic. Phytopathology 18, 143. 3. Hoggan, I.A. (1929). The peach aphid (Myzuspersicae Sulz.) as an agent in virus transmission. Phytopathology 19, 109-123. 4. Hoggan, I.A. (1931). Further studies on aphid transmission of plant viruses. Phytopathology 21, 199-212. 5. Francki, R.I.B., Mossop, D.W.,...

Thrlps as Tospovirus Hosts

Replication of Tospoviruses in Thrips Considering the morphological similarity of TSWV to bunyaviruses, Milne and Francki 39 suggested that TSWV might replicate in thrips. The first claim that TSWV multiplied in its vector was made in 1987 by Cho et al. 40 . They showed that the virus titer decreased between 4 and 10 days after acquisition but increased after 19 days. Conclusive evidence was obtained by Ullman et al. 3 and Wijkamp et al. 4 , The former authors measured the titer of the...

Thrips Vectors and Tospovirus Transmission

Pittman 7 discovered that Thrips tabaci transmits TSWV It was believed for decades that this species was the main vector of TSWV, although other vector species were known 8 , However, the vector status of T. tabaci has been challenged in recent years 9 and appears more complex than previously surmised 10, 11 . The cosmopolitan T. tabaci seems the main vector of this virus in tobacco in Eastern Europe, whereas Frankliniella schultzei is considered the main vector in tobacco in the United States...