EFFECT OF ENGLISH, SIBERIAN, AND CHINESE ELMS ON THE ATTACK BEHAVIOR AND BROOD SURVIVAL OF SCOLYTUS MULTISTRIATUS (COLEOPTERA: SCOLYTIDAE)

Abstract

AbstractScolytus multistriatus female adults demonstrated a distinct preference for English and Siberian elm over Chinese elm in attacking bolts and establishing egg galleries. Density of attacks appeared related to bark roughness of the exposed bolt. A ranking of elm species suitability for S. multistriatus is thus possible. Some of the females forced to attack Chinese elm died after making nuptial chambers but before establishing egg galleries. Egg production by females was unaffected by attack densities observed, elm species, or the place where the trial was conducted. In the laboratory, survival from egg to adult was lower in Chinese elm than in English or Siberian elm. Ability of the larvae to mine outer bark at high densities is believed to be a response to intraspecific competition and probably enhances survival. The first estimates of subcortical population parameters are presented for this species in North America. Adaptive value of variations in relationships between the beetle and various elm species is discussed.