Singing all day long: the role of substrate-born vibrations in mating behaviour of the leafhopper Empoasca vitis (Göthe)

Many insect species use chemical signals to bring together potential partners, however there are several alternatives to accomplish such a task. Substrate-borne vibrational signals are widespread in many insect taxa included Hemiptera, where they are often fundamental for the mating behaviour (Cocroft & Rodriguez, 2005). The leafhopper Empoasca vitis is a grapevine pest with holarctic distribution. Despite its economic importance (Alma, 2002), to date the mating behavior and associated vibrational communication of this species are still undescribed. For the first time in the present study, by means of laser vibrometer and behavioral observations, we investigated the mating behavior of E. vitis, describing the role of subtrate-borne vibrational signals in pair formation and the mating activity throughout the day. Pair formation begins with male’s call, which consists of a train of pulses (S1) at growing intensity, followed by a longer harmonic signal (S2, Fundamental Frequency 124,17 ± 8,36 Hz) and sometimes by one single or double stronger pulse (S3). The female replies in response of the male call with a “chirp” and a duet is maintained until the copula occurs. Even if the males call throughout the day, the number of matings is lower during the night. The knowledge acquired thanks to this work may contribute to the development of a specie-specific mating disruption approach, as it has already been done for another insect leafhopper pest, Scaphoideus titanus (Eriksson et al., 2012)