Aphid attraction and preference for soybean and pepper plants infected with potyviridae

The progress of nonpersistently transmitted virus epidemics can be substant ially altered by the degree of aphid attraction and preference for virus-in fected plants. Our objective was to determine whether color or odor-mediate d cues of plants infected with Potyviridae mediate aphid attraction. We fou nd that Myzus persicae (Sulzer) and Rhopalosiphum maidis (Fitch) preferred alighting on intensely (highly saturated) yellow than on green (plant-like) or brown (soil-like) ceramic tiles, and expressed no preference for landin g on leaves infected with soybean mosaic virus (SMV) or on chlorophyll-defi cient soybean leaves. Furthermore, neither aphid species showed odor-mediat ed attraction to leaf extracts of SMV-infected leaves. Also, R. maidis rema ined longer on uninfected than on SMV-infected soybean plants before taking flight, although M. periscae exhibited no preference. Neither aphid specie s had a preference to remain on healthy or potato virus Y-infected plants. Therefore, we conclude that both aphid species when landing are equally lik ely to alight on healthy or SMV-infected soybean plants in the field, but R . maidis is likely to remain a shorter time on SMV-infected than on healthy plants before taking off. The fact that aphids leave the infected plant so on after probing increases the probability of Ending another plant and maki ng an infective probe before the vector loses its potential to inoculate th e virus. These results could be used to increase the precision of existing simulations models, such as the one previously developed for SMV.