Reznik, S. Y., Vaghina, N. P., & Voinovich, N. D. (2011). Effects of previous experience and age-related changes on host eggs parasitization by Trichogramma buesi Voegele (Hymenoptera, Trichogrammatidae) females. Entomological Review, 91(3), 281-291.

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The influence of the previous parasitization experience and age-related endogenous changes on the parasitization of Sitotroga cerealella Oliv. (Lepidoptera, Gelechiidae) eggs by Trichogramma buesi Voegele (Hymenoptera, Trichogrammatidae) females was estimated in the laboratory conditions. The experiment included two exposures separated by a period lasting from 0 to 20 days at 20°C. The first exposure lasted for 4 h and was conducted at a temperature of 25°C which promoted parasitization. The second exposure lasted 48 h and was conducted at a temperature of 15°C which inhibited parasitization. The survival of the control females (deprived of the hosts at the first exposure) was slightly higher than that of the experimental females. The mean number of mature eggs and the mean fecundity during the second exposure were lower in females that parasitized during the first exposure than in the controls and in females that rejected the host during the first exposure. The proportion of T. buesi females that parasitized S. cerealella eggs during the second exposure was much higher among the females that started parasitization during the first exposure than among controls and among those that rejected the host during the first exposure. This effect of the previous parasitization experience on the following parasitization of the same host species persisted for 16 days. However, on day 20 after the first exposure the proportion of the parasitizing individuals among the experienced females was the same as among the controls and those that rejected the host during the first exposure. This sharp decay in the effect of experience coincided with an increase in mortality and with a decrease in the proportion of parasitizing females among the controls. Thus, the experience-induced behavioral changes per se could be considered as practically permanent, since the period of their persistence is close to the female active life span.