Bottom up effects of nutrients and water on black vine weevil Otiorhynchus sulcatus (Coleoptera: Curculionidae) and Heuchera micrantha "Palace Purple" (Saxifragacea)

Abstract

This thesis investigated: a) the effect of fertilization and water regimes on chemistry and growth of Heuchera micrantha and the effect of plant quality on black vine weevil performance b) the effect of black vine weevil larvae on Heuchera micrantha growth and c) the effect of fertilization on tolerance of Heuchera micrantha plants to different densities of black vine weevil.

I found a positive effect of nitrogen fertilization and water on plant chemistry and growth. Leaf nitrogen, carbon: nitrogen ratio, and phenols were strongly affected by nitrogen fertilization.

Fertilization had no effect on adult and larval survivorship, ovipositional period or feeding preference of black vine weevil adult. Larvae had a strong effect on top and root biomass and this effect increased with increasing levels of fertilizer when water was not limited. Fertilizer did not increase tolerance of Heuchera micrantha to adults or larvae of black vine weevil.