The effects of the broad-specificity lipase inhibitor, tetrahydrolipstatin, on the growth, development and survival of the larvae of Epiphyas postvittana (Walker) (Tortricidae, Lepidoptera)

Effects of tetrahydrolipstatin (THL) on larval growth to 21 days and percentage pupation of Epiphyas postvittana larvae. [Display omitted] ► Epiphyas postvittana larvae were fed tetrahydrolipstatin (THL) in their diet. ► Survival, growth rate, development, and percentage pupation were reduced. ► Enzyme activity of midgut lipase was reduced in THL-fed larvae. ► Gene expression of gastric lipase genes is up-regulated in THL-fed larvae. The effects of the lipase inhibitor, tetrahydrolipstatin (THL), on neonate Epiphyas postvittana (Walker) (Lepidoptera, Tortricidae) larvae were investigated by feeding on control artificial diets (with and without 2% ethanol) and diets containing 2% ethanol and one of three concentrations of THL (0.011%, 0.037% and 0.11%). Small but significant reductions in growth rate, percent pupation and time to pupation were observed for larvae feeding on 2% ethanol control diet compared with standard control diet, but larger reductions in all parameters occurred with increasing THL concentration. Third instar larvae fed 0.011% THL in the diet had 40% of the midgut lipase activity in the relevant control larvae and showed up-regulation of gene expression of the gastric lipase-like family but not the pancreatic lipase-like family of midgut lipases.