Biology and Host Specificity ofCornops aquaticum(Broner)1(Orthoptera:Acrididae), a Potential Biological Control Agent for Waterhyacinth2

Abstract

The waterhyacinth grasshopper, Cornops aquaticum (Bruner), was studied in Uruguay and Argentina to determine if it is sufficiently host specific to introduce into the United States as a control agent against waterhyacinth, Eichhornia crassipes (Mart.) SolmsLaubach. Under field conditions, only E. crassipes , E. azurea Kunth, and rarely Pontederia cordata L. sustained damage, and only the former 2 species were acceptable for oviposition and egg development. Based on the high degree of feeding preference for Eichhornia spp. in the tests and the dependence of the insect on members of this genus for its development, C. aquaticum is considered sufficiently specific to Eichhornia spp. to be potentially useful to introduce for biological control of E. crassipes in the United States.