Saltcedar is an invasive, non-indigenous plant that degrades many riparian areas in the western U.S. A leaf beetle from central Asia has been introduced to control saltcedar, but it must tolerate a wide range of environmental conditions where the plant is found, including some which have become highly salinated. We conducted laboratory experiments to determine whether feeding beetles are able to assess tissue nitrogen and salt levels, and whether these factors affect growth and reproductive potential. Larvae showed a preference for plants grown with nitrogen augmentation over those grown under low N conditions, but salt had little impact on host choice; however, larval growth rate was approx. 20% greater on plants with both enhanced nitrogen and salt levels compared with other treatments. Adult responses will be assessed during the summer. Results so far indicate that this biological control agent should be able to develop successfully across most environments, including those heavily afffected by elevated soil salt levels.
Species 1: Coleoptera Chrysomelidae Diorhabda elongata (saltcedar leaf beetle)
Species 2: Tamaricales Tamaricaceae Tamarix parviflora (saltcedar, tamarisk)
Keywords: plant insect interactions, invasive riparian plants
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA