Inoculation of Pea Enation Mosaic Virus by the Green Peach, Potato, and Foxglove Aphids1

Abstract

Three aphid species, the green peach aphid, Myzus persicae (Sulzer), the potato aphid, Macrosiphum euphorbiae (Thomas), both reported vectors of pea enation mosaic virus (PEMV), and the foxglove aphid, Acyrthosiphon solani (Kaltenbach), previously reported as a nonvector, were tested for their capability of inoculating PEMV to pea leaves during brief test probes. Both the green peach and potato aphids proved capable of inoculating PEMV to peas with single probes of 15 seconds or less in duration. The foxglove aphid, an inefficient vector in transmitting virus to only 6 of 50 test plants during a 48-hour inoculation access period, failed to transmit PEMV during probes of up to 60 seconds in duration. Observation of sheath saliva left behind in pea leaves after probes of 15 and 60 seconds by the 3 aphid species revealed that penetration of the epidermis and parenchyma is primarily intercellular. Data would indicate that inoculation of PEMV by the green peach and potato aphids during brief test probes is intercellular in the epidermis.