Densovirus infection facilitates plant-virus transmission by an aphid

Area of Science:

• Plant-insect-virus interactions
• Insect virology
• Plant pathology

Background:

• Interactions among plant viruses, insect vectors, and host plants are well-documented.
• The role of insect viruses in these tripartite interactions has been largely overlooked.
• Understanding these dynamics is crucial for managing plant diseases transmitted by insects.

Purpose of the Study:

• To investigate the impact of Myzus persicae nicotianae densovirus (MpnDV) on aphid behavior and plant virus transmission.
• To elucidate the mechanisms by which MpnDV influences its insect host and plant virus spread.
• To explore novel strategies for controlling insect vectors and plant viruses.

Main Methods:

• Bioassays were conducted using green peach aphid (Myzus persicae), potato virus Y (PVY), and MpnDV.
• RNA interference (RNAi) was employed to study gene expression.
• Gas chromatography-mass spectrometry (GC-MS) was used to analyze volatile compounds.

Main Results:

• MpnDV infection significantly enhanced the production of (E)-β-farnesene (EβF) in aphids by up-regulating the MpFPPS1 gene.
• MpnDV-infected aphids exhibited increased locomotor activity and population proliferation compared to uninfected aphids.
• Enhanced aphid activity and proliferation led to a significant increase in PVY transmission rates in tobacco plants.

Conclusions:

• Insect viruses can facilitate plant virus transmission by modulating insect vector behavior and population dynamics.
• MpnDV acts as a '।।।।।।।' vector, increasing aphid dispersal and proliferation, thereby enhancing PVY spread.
• These findings offer new avenues for developing integrated pest and disease management strategies targeting insect vectors.