Diapause induction in the codling moth, Cydia pomonella: effect of prediapause temperatures

Abstract

The effect of four prediapause temperatures (18, 22, 26 and 30 °C) on the photoperiodic response of the codling moth, Cydia pomonella (L.), was studied under controlled conditions. The highest rates of diapause were recorded, for all day‐lengths, at temperatures of 22 and 26 °C while relatively lower rates of diapause were elicited at 18 and 30 °C. The same trend was demonstrated by projecting the values of the critical photoperiod which induces 50% diapause (= CPhP50) over the prediapause temperature. The change in diapause incidence as a function of photoperiod, at all prediapause temperatures, exhibited a response characteristic of long‐day insects, i.e. high rates of diapause at short days (12–13.5 h) and a decrease in diapause incidence at long days (14–15 h). The results for temperatures 22, 26 and 30 °C support the view that lower prediapause temperatures enhance diapause induction, at a given photoperiod, while higher temperatures tend to avert or diminish the process. On the other hand, the low rates of diapause obtained at 18 °C contradict this view. Nevertheless, high correlation was found between the laboratory evidence and field data, indicating the adaptability of the Israeli codling moth to subtropical climate.

Variability in diapause propensity within populations of a temperate insect species: interactions between insecticide resistance genes and photoperiodism

“…Similarly, a significantly earlier trend to diapause was recorded in field‐collected RR‐JO individuals relative to both SS‐JO and RS‐JO ones, but also relative to SS‐WA individuals. Because of local climate conditions, variation between both RR‐JO and SS‐WA individuals could partly result from additional environmental influences on diapause induction, which may express through both fruit maturity (Riedl, 1983) and prediapause temperatures (Steinberg et al ., 1992). The similar responses displayed by both SS‐JO and SS‐WA individuals, however, suggest that day length was a common major triggering factor for diapause induction in these two separated localities, but also support pleiotropic effects of resistance in explaining the diapause response displayed by RR‐JO individuals.…”

“…Consequently, the geographical adaptations of this species display a clinal‐type latitudinal variation of the diapause structure resulting in an increasing voltinism towards southern latitudes in the northern hemisphere (Shel’Deshova, 1967; Riedl & Croft, 1978). Other factors such as food availability and quality (Brown, Berryman & Bogyo, 1979; Riedl, 1983) and prediapause temperatures (Steinberg, Podoler & Applebaum, 1992) are regarded as modifiers of the diapause response to decreasing day‐lengths. In south‐eastern France, two complete generations of adults occur each year.…”

Maternal temperature has different effects on the photoperiodic response and duration of larval diapause in blow fly (Calliphora vicina) strains collected at two latitudes

“…Insects are ectothermic and so their physiology, metabolism and development are dependent to a very great extent on the ambient temperature (Beck, 1991). Increasing the constant temperature is known to reduce the incidence of diapause in a variety of insect species, for example within the Lepidoptera, Pyrausta (ϭ Ostrinia) nubilalis (Beck & Hanec, 1960), Diatraea grandiosella (Chippendale & Reddy, 1973), Cydia pomonella (Steinberg et al, 1992); Sesamia nonagriodes (Eizaguirre et al, 1994), in the parasitoid wasp Nasonia vitripennis (Saunders, 1965) and among the Diptera, in Drosophila spp. (Kimura, 1982;Kimura, 1988;Saunders & Gilbert, 1990;Yoshida & Kimura, 1994), Haematobia irritans (Lysyk, 1992), Sarcophaga argyrostoma (Saunders, 1975) and Protophormia terraenovae (Vinogradova, 1986).…”

Assessment of control strategies against Cydia pomonella (L.) in Morocco

“…It infests all production areas of apple, pear, quince, and walnut (Shel'Deshova 1967). Its wide distribution area, from cool temperate climates to the Mediterranean climate, results from its effective colonisation favored by human action and strengthened by its optional diapause (Steinberg et al 1992). Codling moth occurs one to five generations (the latest generation is mostly partial) per year in different parts of the world.…”