Reznik, S. 2011. Ecological and evolutionary aspects of photothermal regulation of diapause in Trichogramma. Zhurnal evoliutsionnoĭ biokhimii i fiziologii, 47(6), 434.

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Facultative winter diapause in the genus of Trichogramma Westw. (Hymenoptera, Trichogrammatidae), like in most other insect species, is regulated by photoperiod and temperature. Their prepupae are diapausing, but sensitivity to temperature and day length (environmental cue factors inducing diapause) is characteristic of all stages of development from embryo to the egglaying female. The environmental cues can affect not only the current, but also the next generations. Under the natural conditions, the photothermal regulation provides the timely diapause induction coordinated both with the astronomical season (the photoperiodic response) and with the peculiarity of the given year (the thermal response). The special experiments revealed “rudimentary responses” that had lost their adaptive role. The results of these studies have proved once more that the specificity of photoperiodic and thermal diapause-regulating responses, their relative importance, and association with sensitive stages of development are determined not only by the ecological peculiarities of different insect taxa, but also by their previous evolution.