Management of Listronotus sparsus (Say), a weevil pest of celery and parsley in Florida

Listronotus sparsus (Coleoptera: Curculionidae) has recently emerged as a pest of celery and parsley in Florida. Female adults deposit eggs under the surface of petiole and crown tissues, where larvae subsequently feed and reduce the vigor and quality of the crops. Field experiments were conducted between 2021 and 2023 to compare the efficacy of insecticides considered for L. sparsus management. In celery, foliarly applied oxamyl was the most effective insecticide, reducing weevil injury and the number of larvae. In addition, foliar applications of cyantraniliprole and novaluron showed trends for suppressing weevil infestations. In parsley, oxamyl was not evaluated. However, two foliar applications of novaluron, a premix of novaluron and acetamiprid, cyantraniliprole, thiamethoxam, and a tank-mix of cyantraniliprole and thiamethoxam all provided significant weevil control. One drench application of cyantraniliprole, thiamethoxam, a tank-mix of cyantraniliprole and thiamethoxam, and a premix of chlorantraniliprole and thiamethoxam also reduced weevil injury and infestations. These field trials have supported the first weevil management recommendations for celery and parsley in Florida. These field trials have also supported requests for the registration of novaluron for use on celery and parsley.