Abstract
Mechanical and aphid inoculations were compared as modes for screening cowpeas for resistance against cowpea aphid-borne mosaic virus (CAMV). Aphid transmission of CAMV could vary depending on whether the test host is aphid-resistant or aphid-susceptible. In aphid-resistant lines aphid inoculation was better than mechanical inoculation, inspective of the reaction of the line to CAMV. Mechanical inoculation, however, proved to be a better method of CAMV transmission in aphid-susceptible lines. Aphids were unable to acquire CAMV from the aphid-resistant source plant with the same ease as they did from susceptible ones. Generally, only slight differences were observed between mechanical and aphid transmission of CAMV. Therefore mechanical inoculation is to be preferred over aphid inoculation for screening cowpeas against CAMV, because the former is easier, faster and involves less variables.
