Adaptation Features of Diapause Duration of the Gypsy Moth Lymantria dispar (L.) from Populations of Different Latitudinal Origination
V. I. PONOMAREV1, G. I. KLOBUKOV1, A. V. ILYINYKH2, I. M. DUBOVSKIY3
1Institute Botanic Garden, 620144, Ekaterinburg, 8 marta str., 202а
2Institute of Systematics and Ecology of Animals, Siberian Branch of RAS, 630091, Novosibirsk, Frunze str., 11
3Novosibirsk State Agrarian University, 630039, Novosibirsk, Dobrolyubova str., 160
Keywords: Lymantria dispar (L.), сумма эффективных температур, диапауза, оцепенение, отрождение, gypsy moth, diapause, quiescence, sum of effective temperatures, eclosion
Abstract
The analysis of influence of the sum of effective temperatures (SET) that gypsy moth embryos receive in midsummer-autumn period until overwintering on diapause duration and SET of eclosion, and the assessment of the effect of short-term temperature rising during dormancy period on eclosion duration and diapause strength have been performed. The effect of the midsummer-autumn SET on diapause duration and on the SET of spring eclosion subject to conditions of diapause and following quiescence was found. We showed that short-term rising of temperatures over the development threshold led to proportional decrease of eclosion duration in case the SET of eclosion was lower than 200 degree days. If the SET of eclosion was higher than 200 degree days, the effect of this exposure had either no effect on the eclosion duration, or led to stronger dormancy. The short-term temperature rising led to increased mortality of the embryos which received low midsummer-autumn SET (about 400-450 degree days with threshold about 7 оC). The embryos that received high midsummer-autumn SET (about 1300-1500 degree days with threshold about 7 оC) showed no increased mortality. Based on these results, we suggest that the populations of south origination have stronger diapause due to the adaptation to the short term casual temperature risings above the embryo development threshold in winter-spring period, that can lead to the untimely eclosion of gypsy moth larvae.
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