Spatial and temporal genetic variability in French populations of the peach–potato aphid, Myzus persicae

Abstract

The peach-potato aphid, Myzus persicae (Sulzer), has a complex reproductive mode in which some lineages reproduce by continuous parthenogenesis, whereas others reproduce sexually once a year. The climate is thought to act directly on the reproductive mode, because sexual eggs are the only form that can resist frost in cold regions. Sexual reproduction necessitates an obligatory host alternation that may result in long-distance dispersal. Here, we examined the genetic variability at seven microsatellite loci of populations of M. persicae in France, where both reproductive modes occur. We provide clear genetic evidence that the breeding system affects genotypic variability, as cyclically parthenogenetic aphids are far more variable than their obligately parthenogenetic counterparts. A temporal decrease in genetic variability and a temporal genetic differentiation effect suggest the existence of selective factors that play an important role in shaping the genetic structure of M. persicae populations. Lastly, differences in the population structure between reproductive modes suggest that the migration associated with the change of host during sexual reproduction lowers the level of population differentiation.

Evidence for gene flow and local clonal selection in field populations of the grain aphid (Sitobion avenae) in Britain revealed using microsatellites

“…Similar studies have also revealed differences in the genetic structuring of natural aphid populations, relating to lifecycle strategy and clonal selection (eg Simon et al, 1999;Guillemaud et al, 2003). The genetic structuring reflects flight behaviour (eg low genetic differentiation over a wide area for highly migratory species), although selection for lifecycle types better adapted to the climate in particular regions is also apparent (eg Massonnet et al, 2002;Guillemaud et al, 2003).…”

Spatial and temporal dynamics of Myzus persicae clones in fields and suction traps

“…Sexually reproducing (holocyclic) populations are only present in peach-growing areas, whereas, asexual populations are more widespread, remaining more or less active all year round depending on temperature. Myzus persicae sexual populations are genetically diverse ( Wilson et al , 2002;Fenton et al , 2003;Guillemaud et al , 2003;Vorburger et al , 2003a ). Studies of long-term asexual populations of this aphid show instead an extreme effect of genetic bottlenecking ( Fenton et al , 1998( Fenton et al , , 2005Zamoum et al , 2005;Kasprowicz et al , 2007;van Toor et al , 2007 ).…”

“…The application of high resolution genetic markers to samples in peach-growing areas, taken from peach, from plants growing near peach and from suction traps, have all confirmed that these are diverse populations. Some genotypes have expanded asexually at local scales, ranging from a small number of clonal individuals on neighbouring branches in peach orchards ( Fenton et al , 2003 ) to many clonal individuals spread over a wide area ( Guillemaud et al , 2003;Vorburger et al , 2003a ).…”

Temporal Dynamics and Linkage Disequilibrium in NaturalCaenorhabditis elegansPopulations

“…There are as yet few molecular studies of the same population over time (Viard et al 1997;Guillemaud et al 2003;Meunier et al 2004;Charbonnel and Pemberton 2005;Trouvé et al 2005). However, to obtain a direct picture of dynamic phenomena such as migration, recombination, selection, or population extinction and to detect variation over time, temporal surveys of populations are required.…”