Do aphids spread plant diseases

Answer 1

Viral is the type of disease which aphids transmit.

Specifically, the insect in question (Aphidoideasuperfamily) applies mouthparts known as stylets to break through plant tissue in order to access phloem and xylem sap. In the process, an aphid injects toxic saliva and leaves sheaths around entry-points. An aphid's mouthparts, saliva and sheaths all may transmit viruses to the plant, which is weakened by the loss of vital life-sustaining hormone-, mineral-, sugar-enriched watery solutions.

Answer 2

Yes, aphids spread plant diseases.

Specifically, animals and plants are susceptible to bacterial, fungal and viral diseases any time that their surfaces are punctured. Aphids (Aphidoidea superfamily) have piercing mouthparts that are capable of breaking through plant leaves, stalks and stems. They additionally leave behind stylets to keep the punctures open and transmit pathogens and toxins through saliva.
Yes, aphids spread plant diseases.

Specifically, the insect in question applies sharp mouthparts known as stylets to break into plant tissue. They are in search of the plant's life-giving phloem and xylem sap. In the process, they introduce pathogens by way of the sheaths which they leave around entry-points, the noxious saliva which they introduce onto plant parts, and the fungal-attracting honeydew which they excrete on plant surfaces. All three behaviors may result in the ultimate overwhelming of the plant by bacterial, fungal and viral attacks.