Nymphs and adults of Paulinia acuminata accepted five aquatic macrophytes out of 20 plant species offered during 12 days: Pistia stratiotes, Salvinia auriculata, S. minima, Azolla sp. and Ludwigia natans. The low survival rates obtained on Azolla sp. for adults (26%) and on L. natans for nymphs (40%) and adults (30%) indicate that these two aquatic macrophytes may represent alternative food sources. Cage experiments with P. statiotes and S. auriculata in the field resulted in 51-64% increase of fresh plant weight without P. acuminata and in 40-45% decrease, both compared to the initial plant weight, when 20 grasshoppers (nymphs and adults) were present. All these data reinforce the potential of P. acuminata as biological control agent for specific aquatic macrophytes.
Paulinia acuminata; Pauliniidae; food preference; aquatic macrophytes