Selective herbivory on low-zinc phenotypes of the hyperaccumulator Thlaspi caerulescens (Brassicaceae)

摘要: The European plant Thlaspi caerulescens hyperaccumulates zinc in its leaves to concentrations exceeding 2 %. This may represent a defense against herbivory, as shown by reduced feeding on plants grown high-zinc versus low-zinc substrates. However, the more evolutionarily relevant comparison involves whose metal content differs due genetic rather than environmental causes. In our study, were uniform hydroponic solution containing 10 mg/l Zn. Foliar Zn measured, and of contrasting concentration chosen for trials using Pieris napi oleracea larvae. Comparisons revealed no statistically significant preferences when young larvae used, but highly avoidance high-Zn later-instar caterpillars, suggesting that hyperaccumulation could evolve response selective pressures herbivory.