Mating disruption of a grapevine pest using mechanical vibration: from laboratory to the field

Mating disruption using mechanical vibrations is a novel idea for integrated pest management of insect pests. We present results of research on using artificial vibrational noise to prevent mate recognition and localization mediated by vibrational signals in the grapevine pest Scaphoideus titanus. Building on the proof-of-concept published previously, mating trials were set up in laboratory to determine the amplitude threshold for playback efficacy and reveal the mechanism of its function, while field trials were performed to validate this threshold and explore the possibility of reducing energy use by exploiting the diel pattern of this species' mating activity. The threshold obtained in laboratory trials - 15 μm/s peak amplitude - was confirmed by measurements of attenuation and insect mating in field cages at successive distances from the source. We also discovered that shutting off the disruptive noise between 1000 and 1800 hours did not reduce efficacy of the method in the field, allowing energy saving in this period. The noise had an all-or-nothing effect on S. titanus mating behaviour and we were unable to ascertain the exact mechanism of the communication breakdown, but the approach appears robust enough to merit largescale testing in the future

Active space and the role of amplitude in plant-borne vibrational communication.

Unlike airborne signals, substrate-borne vibrational signals are confined within the size and shape of their medium of communication, which in the case of small arthropods often coincides with the host plant. By following the substrate continuity, a vibrational signal creates a more or less complex active space network that enables communication between individuals. Due to the heterogeneity of plants, physical properties of the substrate can vary in the efficiency of signal transmission and in the diffusion of signals along the tissues. Under such circumstances, the identification and location of a potential partner may be a difficult task. Amplitude cues can be of great importance in orientation to the source of a vibrational signal by providing information about both direction and distance. As examples, we present two case studies on mating behavior of a leafhopper and a planthoppe