Geographic variability in demographic performance of the potato moth, Phthorimaea operculella(Zeller) (Lepidoptera: Gelechiidae), in Australia

Abstract

AbstractMeasurements of several parameters of demographic performance for 16 field-derived Australian populations of Phthorimaea operculella (Zeller) were obtained under laboratory conditions. Fecundity, female weight and low temperature development rates were the most important parameters contributing to differences between populations. It is suggested that the increased fecundity and female weights found in warmer regions may be selected for in part by the continuous high mortality imposed by parasitoids, which have a reduced impact in the colder parts of P. operculella's range. A more rapid development rate in populations from colder areas is probably due to selection for a decreased lower threshold temperature in these areas, indicating better survival characteristics under cold conditions.