Transmission of Potato virus Y in Tobacco Plants by Myzus persicae nicotianae and M. persicae s.str.

The transmission efficiency of Potato virus Y (PVY) from and to tobacco plants by Myzus persicae nicotianae, a tobacco specialist, and M. persicae s.str. (Hemiptera: Aphididae), a generalist, was evaluated. In direct transmission tests, 1,004 spring migrants collected as nymphs from peach and 1,434 wingless females from 12 clonal lineages of both taxa were examined. Both the winged and wingless females were starved before being transferred individually for a 3-min acquisition period on infected plants and then moved to healthy plants for a 10-min inoculation access period. Little variation in transmission efficiency was observed. Although not statistically significant, M. persicae nicotianae was slightly more effective. This may suggest similar genetic properties (e.g., virion receptors in mouthparts) between the taxa in relation to virus transmission. M. persicae s.str. transmitted the virus less efficiently when a shorter inoculation period was given. This may indicate differences in probing behavior during the early phase of host selection. Nevertheless, behavioral differences related to host selection have been found using arena tests with infected and healthy tobacco plants where 180 winged females from each taxon were tested. M. persicae s.str. had significantly higher propensity to transmit PVY than M. persicae nicotianae (31.9 versus 15.3%).