Potential bottom-up control of Metamasius callizona in Florida, USA

Abstract

Metamasius callizona (Chevrolat) (Coleoptera: Curculionidae) is an invasive weevil destroying Tillandsia utriculata L. (Bromeliaceae) populations in Florida, USA. A T. utriculata population in Belize coexists with M. callizona without adverse effects. Tillandsia utriculata and M. callizona from Belize and Florida were studied in the laboratory to determine how Belize T. utriculata can coexist with Belize M. callizona, using Florida and Belize T. utriculata, as well as pineapple, Ananas comosus (L.) Merr. (Bromeliaceae), as host plants. Florida M. callizona on pineapple leaves produced more eggs per female per day and had a shorter developmental time and pupation period, as well as a smaller adult width, than Belize M. callizona. Florida and Belize weevils did not differ significantly in rates of egg hatch, pupation, and adult emergence. Florida M. callizona laid similar numbers of eggs per day on Florida and Belize T. utriculata. Egg hatch rates were similar on pineapple and Florida and Belize T. utriculata. Pupation rates were similar on pineapple and Florida T. utriculata leaves; no larvae on Belize T. utriculata attained fourth instar. Field and laboratory observations revealed that Belize and Florida M. callizona mined Belize T. utriculata without destroying the meristem, allowing plants to survive, but Belize M. callizona destroyed the core of pineapple tops. Soluble solids were greatest in pineapple and least in Belize T. utriculata. Leaf toughness was greatest in pineapple and least in Florida T. utriculata. Metamasius callizona biology and behavior and T. utriculata plant characteristics may drive the severity of weevil damage on populations of T. utriculata. The discovery of a T. utriculata population in Belize coexisting with M. callizona offers a possible way to control M. callizona in Florida.