Substrate-Borne Vibrational Communication in the Vector of Apple Proliferation Disease Cacopsylla picta (Hemiptera: Psyllidae).

ABSTRACT

Cacopsylla picta (Förster, 1848) (Hemiptera Pysllidae) is the main vector of apple proliferation, a phytoplasma-caused disease. It represents one of the most severe problems in apple orchards, and therefore, there is a mandatory requirement to chemically treat against this pest in the European Union. Sexual communication using substrate-borne vibrations was demonstrated in several psyllid species. Here, we report the characteristics of the vibrational signals emitted by C. picta during courtship behavior. The pair formation process can be divided into two main phases identification and courtship. Females initiate the communication on the host plant by emitting trains of vibrational pulses and, during courtship, if males reply, by emitting a signal consisting of a series of pre-pulses and a 'buzz', a duet is established. Moreover, a scanning electron microscopy investigation showed the presence of a stridulatory structure on the thorax and wings of both sexes, whereas the video recordings elucidated associated wing movement. The results provide new information about the biology of this phytoplasma vector and could form a basis of an environmentally friendly pest management strategy.