Aphid-Transmitted Plant Viruses

Insects, mites, nematodes, and protists.

Aphids account for the transmission of 50% of the insect-vectored viruses and are exquisitely designed for their roles as vectors.

Aphid populations can increase at extraordinarily high rates due to asexual reproduction, potentiating disease epidemics and furthering the spread of viruses.

<p>A greater understanding of mechanisms behind the transmission process is important in determining how forces have played a role in shaping the evolution of plant viruses.</p> Signup and view all the answers

<p>It appears to be required for aphid transmission and may play a role in vector specificity.</p> Signup and view all the answers

<p>Symbionin is hypothesized to be an essential factor in transmission functioning to stabilize virions in the aphid haemolymph.</p> Signup and view all the answers

<p>They achieve aphid transmission competence by associating with luteoviruses in plants dually infected by both viruses. The luteovirus helper virus contributes to the transmission of the umbravirus by encapsidating the latter’s genomes with its CP.</p> Signup and view all the answers

<p>The primary difference is that once an infection in the aphid has been established, the association remains permanent for the rest of the life of the insect and virus may be transmitted to offspring through a transovarial route.</p> Signup and view all the answers

<p>Potyviruses and Sobemovirus families</p> Signup and view all the answers

<p>Viral capsid protein</p> Signup and view all the answers

<p>They function as a bridge, mediating the binding of virions in the stylet of the aphid vector</p> Signup and view all the answers

<p>When an aphid feeds on an infected plant and then feeds on an uninfected plant</p> Signup and view all the answers

<p>Cauliflower mosaic virus adopts a helper-dependent transmission strategy, requiring two viral-encoded nonstructural proteins, P2 and P3.</p> Signup and view all the answers

<p>Caulimoviruses and closteroviruses are well-characterized examples of semipersistent, aphid-transmitted viruses.</p> Signup and view all the answers

<p>Vector specificity is a prominent feature of luteovirus transmission, with compatible interactions between virions and factors in the aphid determining transmission.</p> Signup and view all the answers

<p>The CP (capsid protein) is a primary determinant of transmission for circulative, nonpropagatively vectored viruses, and it also determines vector specificity in luteoviruses.</p> Signup and view all the answers

<p>The large number of potyviruses in 2000, with 91 definitive and 88 tentative potyviruses, indicates their significance in the context of aphid-transmitted plant viruses. This suggests that potyviruses are prevalent and important in the transmission dynamics of aphid-vectored plant viruses.</p> Signup and view all the answers

<p>Aphid vectors mainly belong to the subfamily Aphidinae and possess unique features such as the ability to feed on a wide range of plant hosts, rapid reproduction, and a needle-like stylet for virus delivery. These features contribute to their success as virus vectors.</p> Signup and view all the answers

<p>Circulative viruses are classified as circulative nonpropagative or circulative propagative, depending on whether the acquired virus replicates within the vector. An example of circulative nonpropagative virus is Tomato spotted wilt virus, and an example of circulative propagative virus is Potato leafroll virus.</p> Signup and view all the answers

<p>Nonpersistent virus transmission is characterized by short acquisition and inoculation times, with aphids remaining viruliferous for short periods. An example of a nonpersistent virus is Cucumber mosaic virus (CMV), which is transmitted by aphids in a nonpersistent manner.</p> Signup and view all the answers