Preference for and Suitability of Asian Elm Species and Hybrids for the Adult Elm Leaf Beetle (Coleoptera: Chrysomelidae)

Abstract

Selected elms Ulmus spp. and their hybrids growing at The Morton Arboretum, Lisle, IL, were evaluated in laboratory bioassays for feeding preference and suitability for the adult elm leaf beetle, Pyrrhalta luteola (Müller). No-choice and multiple choice studies revealed that the hybrid U. japonica ✕ U. wilsoniana Accolade was the least suitable for feeding and reproduction by the elm leaf beetle. The hybrid U. japonica-U. wilsoniana X U. pumila Danada and U. pumila (standard) were highly preferred and suitable for feeding and reproduction by adult beetles. Preovipositional period was a function of suitability as adults feeding on the least suitable species/hybrids oviposited later than females feeding on the most suitable elms such as Danada and U. pumila. Suitability had no significant effect on male and female longevity nor did male/female longevity affect suitability or preference of elm species/hybrids evaluated in this study. Less and intermediately suitable species of U. japonica ✕ U. wilsoniana Accolade, U. daridialla, U. japonica, and U. wilsoniana show promise for future elm breeding programs.