Geographical Variation in Responses to Photoperiod and Temperature by Leptinotarsa decemlineata (Coleoptera: Chrysomelidae) During and After Dormancy

Down-regulation of gene expression between the diapause initiation and maintenance phases of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

“…CRALBP is essential in the processing of trans-retinol to 11-cis-retinal (vitamin A) which binds to opsin to form the active photopigment rhodopsin (Noy, 2000). Though there is evidence that CRALBP and vitamin A are involved in insect seasonality (Veerman et al, 1985;Overmeer et al, 1989;van Houten & Veerman, 1990;Claret & Volkoff, 1992;Bosse & Veerman, 1996;Gao et al, 1999), L. decemlineata remains responsive to photoperiodism independent of diapause history (Tauber et al, 1988). Therefore, the decrease in the level of expression in CRALBP observed in this study would appear not to be affecting the ability of L. decemlineata to respond to photoperiodism.…”

Population dependent effects of photoperiod on diapause related physiological traits in an invasive beetle (Leptinotarsa decemlineata)

“…In older studies on diapause development in L. decemlineata, and many other species, behavioral cues, such as burrowing, were used as sole measure of diapause initiation (e.g. de Wilde et al 1955, Goryshin et al 1987, Tauber et al 1988, Senyanake et al 2000. However, it is shown in many studies, including my thesis, that behavior can be highly variable and not necessarily causally linked to an underlying physiological status (such as the size of energy reserves).…”

“…Diapause is driven by short photoperiods experienced by the adult beetles shortly after eclosion (de Wilde et al 1959) although it is positively influenced by low temperature and shortage of food (de Kort 1990). There is population dependent variation in critical photoperiod (CPP) (when 50 % of mature adults initiate diapause), but evidence for the extent of photoperiodic adaptation is not conclusive (de Wilde et al 1959, Danilevski 1965, Tauber et al 1988. Adult beetles destined for diapause normally migrate to the sides of potato fields, or into neighboring forest patches, where they burrow into the soil, to depths between 20 and 80 cm , Milner et al 1992).…”

“…To investigate the burrowing response as an indication of diapause initiation, burrowing into the soil (burrowed into the soil or on the soil surface) was recorded when beetles were 10 days old and had been in the overwintering jars for three days (Tauber et al 1988, Seyanake et al 2000) (II, III). In an additional experiment I assessed burrowing depth of a subset of beetles from Petroskoi (N = 40) and Padua (N = 40) used in study IV.…”

Intraspecific mitochondrial DNA variation in the Colorado potato beetle,Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)

“…Specimens from different parts of North America are morphologically indistinguishable from each other and are considered a single species based largely on similarity in male genitalia (Jacques, 1972(Jacques, , 1988. However, investigations of selected geographic populations from the western and southwestern United State showed differences in host plant affinity (Hsiao, 1978;Hare and Kennedy, 1986;Horton et al, 1988;Tauber et al, 1988a, b), photoperiodic response (Hsiao, 1981), and insecticide resistance (Forgash, 1981;Dively et al, 1987;Hare, 1990).…”