Study of Wild Solanum Species to Identify Sources of Resistance Against the Green Peach Aphid, Myzus Persicae (Sulzer)

The green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), damages potato worldwide. In this study, we investigated 21 Commonwealth Potato Collection (CPC) accessions from seven wild Solanum species in order to identify sources of resistance against the green peach aphid. Test plants of wild potato species were grown from seed. After 4 weeks, 5 wingless adult aphids were put onto each test plant. The number of aphids was counted after 24 h, 7 and 10 days. At the second screening stage, plants were tested after 4 week’s growth, using the same aphid bioassay as in the first stage screen. Results showed that the most resistant Solanum species to M. persicae were S. trifidum and S. palustre and the most susceptible species tested was S. sanctae-rosae. Stability of the detected aphid resistance during plant development was measured by the correlation of repeated tests S. jamesii (CPC 7166) and S. trifidum (CPC 7123) were significantly more correlated than other accessions tested. The number of glandular hairs on these two resistant species was low and medium respectively. Therefore, resistance of these CPC accessions does not appear to depend on the presence of glandular hairs. Based on glasshouse tests, these two CPC accessions may be useful for novel aphid resistance traits in potato to M. persicae.