Evaluation location: Hauts-de-France, France
Myzus persicae and Ma. euphorbiae were reared on S. tuberosum cv. Desiree plants in environmental chambers. For each aphid species, at least 50 nymphs younger than 24 h were transferred in microcages clipped on the lower face of a potato leaf at the third or fourth level from the apex (10 plants with five nymphs per microcage). For each aphid species, two groups of five plants from the same accession or the standard were randomly placed in environmental chambers. Emerged adult aphids were each isolated in a microcage, and their demographic parameters were evaluated every third day during a period equivalent to their prereproductive period (Le Roux et al., 2004). Nymph survival, prereproductive period, that is the period of time from birth until onset of reproduction, adult survival and calculated daily fecundity were assessed for each accession. For each feeding assay, the intrinsic rate of natural increase was calculated.