Variation in the chromosomal distribution of amplified esterase (FE4) genes in Greek field populations of Myzus persicae (Sulzer)

Fluorescence in situ hybridization (FISH) has been used to study variation in the distribution and number of loci with amplified esterase genes in clones established from field populations of Myzux Persicae-group aphids from assorted crops in northern Greece. In that area insecticides have been used extensively on M. Persicae aphid populations. Peach is the primary host, and the one on which annual sexual reproduction occurs. The secondary host field crops include tobacco, on which reproduction is totally parthenogenetic. The insecticides have been used on both kinds of hosts. High levels of resistance based on the amplification of two genes encoding insecticide-degrading esterases are the result. Variation exists in the chromosomal distribution of amplified esterase (FE4) genes in Greek field populations of M. persicae (Sulzer).