The effects of temperature stress and population origin on the thermal sensitivity of Lymantria dispar L. (Lepidoptera: Erebidae) larvae

Increased environmental temperature is one of the most frequent stresses effecting metabolic rate in herbivorous insect species. Our goal was to compare the influence of increased environmental temperature and induced thermotolerance on the activity of midgut phosphatases and brain tissue hsp70 concentration in 5th instar Lymantria dispar larvae originating from an unpolluted and polluted forest. Thermal regimes in this experiment predominantly influenced the ALP activity and it was affected by temperature, population origin, and their combined effect. Tot ACP activity was changed only by the joint effect of temperature and population origin. Brain hsp70 concentration was under a significant individual and joint effect of temperature and population. In both populations, brain tissue hsp70 concentration and ALP activity should be taken under consideration as a battery with biomarker potential for thermal stress in L. dispar larvae as a bioindicator species.