Copulatory signaling and polygamy of glassy-winged sharpshooters (Hemiptera: Cicadellidae)

Authors: Gordon, Shira; Krugner, Rodrigo

Submitted to: Annals of the Entomological Society of America
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/15/2021
Publication Date: 7/1/2021
Citation: Gordon, S.D., Krugner, R. 2021. Copulatory signaling and polygamy of glassy-winged sharpshooters (Hemiptera: Cicadellidae). Annals of the Entomological Society of America. 114(4):522-527. https://doi.org/10.1093/aesa/saab019.
DOI: https://doi.org/10.1093/aesa/saab019

Interpretive Summary: The glassy-winged sharpshooter (GWSS), Homalodisca vitripennis, is an important insect vector of the bacterium Xylella fastidiosa, the causal agent of Pierce’s disease of grapevine. Development of methods to suppress GWSS population growth in vineyards and adjacent habitats requires knowledge on the reproductive biology of the pest. Recently, a mating disruption method based on interference with GWSS pre-copulatory communication was proven effective under experimental field conditions, but additional information is needed to refine the methods prior to commercial implementation. To this end, experiments were conducted to evaluate insect mating behaviors that affect female reproduction. Results showed that both male and female GWSS can mate multiple times, pairs in copulation stay connected for about 15 hours, and individuals emit communication signals during copulation. A greater understanding of key GWSS reproductive behaviors occurring before, during, and after copulation contributes to current research on improvement of the mating disruption method and provides insights for identification of new targets in the GWSS biology.

Technical Abstract: Finding a partner for an insect to mate with may be only part of ensuring successful siring of offspring. Females often exhibit cryptic female choice (CFC) during or after copulation, which can influence whose sperm from her multiple partners is chosen for egg fertilization. Known behavioral mechanisms for CFC include assessment of males by their nuptial gifts, duration of copula, and seminal fluid contents. In this study, mating behaviors that affect reproduction of glassy-winged sharpshooters, Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae) were investigated. GWSS use vibrational communication to determine whether copulation will occur. However, little is known about reproductive behaviors that occur during and after copulation. Results from this study determined that vibrational communication also occurs during copulation. Vibrational signals similar to those emitted during pre-copulatory communication were identified during copulation alongside a new, “hum-like” signal that occurred shortly after the pair joined in copulation. Duration of copulation was on average of 15 hrs, though with a 10-hr range (8.5 to 18.5 hrs) among observed male-female pairs. Finally, both males and females mated more than once. Collectively, results identified key reproductive parameters required for CFC to occur in GWSS. The study expands on the known animals that use CFC and emphasizes the role that copulatory vibrational communication may play. Understanding of insect behaviors necessary for successful production of offspring is important from an ecological perspective and for development of pest control methods.