Potential improvement of Lymantria dispar L. management by quercetin

Lymantria dispar, a polyphagous insect pest, copes with a wide variety of host-specific allelochemicals. Glutathione S-transferases (GST) are important for catalyzing detoxification in L. dispar. Larval mortality, GST activity in midgut tissue and mass of L. dispar with different trophic adaptations (originating from two forests with a suitable host, Quercus robur, and an unsuitable host, Robinia pseudoacacia), differed after feeding on quercetin supplemented diets (2% or 5% w/w). Quercetin inhibited GST most potently in oak forest larvae that were less adapted to flavonoids in their diet. The larvicidal effect of quercetin on L. dispar larvae depended on the host-use history. We believe this is important in strategies for sustainable control of insect pests.