Pea leafminer Liriomyza huidobrensis (Diptera: Agromyzidae) uses vibrational duets for efficient sexual communication

Abstract

The pea leafminer (Liriomyza huidobrensis) is a notorious pest of vegetables and ornamental plants worldwide. Despite a large number of studies on its biology and ecology, the courtship behavior and sexual communication of this species remain unclear. Here, we studied vibrational communication in the sexual interaction of the pea leafminer. On host plant leaves, females and males behaviorally displayed the bobbing-quivering alternation, which finally led to copulation. Moreover, records of laser vibrometry revealed three-signal duets underlying the behavioral alternation. Sexually mature males spontaneously emitted calls (MCs) to initiate the duets. The females rapidly responded to MCs by emitting replies (FRs) that are longer in duration. The FRs further triggered male replies (MRs) in their search for potential partners. Leafminer-produced vibrational signals convey efficient information to partners and generate pair formation on stretched substrates, such as plant leaves and nylon mesh, but cannot elicit responses on dense substrates, such as glass and plastic. Vibrational playbacks of both MCs and FRs can elicit replies in females and males, respectively. This study completely characterizes substrate-borne vibrational duets in a dipteran insect. The discovery of vibrational sex signals in the pea leafminer provides new insights for the development of novel approaches to control the pest and its relative species.

Female adult puncture-induced plant volatiles promote mating success of the pea leafminer via enhancing vibrational signals

“…In the pea leafminer, the playback of female response signals is sufficient to elicit mate-searching behaviour in all males [28]. To increase the vibration-based trap effect, adult insects must be aggregated on the same substrates.…”

“…Therefore, HIPVs probably play additive roles in the sexual encounters and communications of herbivorous insects. Although pheromones are almost ubiquitous among arthropod species and effective over short to long spatial ranges [26,27], agromyzid flies use vibration for sexual communication on leaves [28] and the mating systems of specific insect species may even lack sex pheromones [29,30]. Under these circumstances, plant volatiles and conspecific species-induced HIPVs provide a reliable signal for the conundrum of habitat location and sex encounter [16].…”

“…Recently, we reported that the leafminer individuals use vibrational duets for sexual communication on plant leaves. The playback of these sexual signals can elicit orientation behaviours in the opposite sex, implying that vibrational signals have potential applications in the trapping control of Liriomyza pests [28]. Given that adult females puncture leaf surfaces with ovipositors to facilitate feeding and oviposition and induce host plants to release a specific blend of volatiles, HIPVs may serve as important cues for sexual encounters.…”

Flies getting filthy: The precopulatory mating behaviours of three mud-dwelling species of AustralianLispe(Diptera: Muscidae)

“…Males are unique in that they perform side-ways 'hops' during courtship, which may act as a visual signal like the side-to-side dances exhibited by male L. cana (White et al 2020). Also unique to this species is that while holding the females from behind, male L. xenochaeta vigorously 'thump' their mid-legs and 'flick' their wings, which almost certainly produces vibrational and aural cues, as in species of Drosophila (Fabre et al 2012) and Liriomyza (Ge et al 2018). This suggests that rather than solely as a form of mate guarding, 'holding' also serves to establish female receptivity in the lead-up to matingthis may also be true for L. sydneyensis and L. cana.…”

Female answer specificity to male drumming calls in three closely related species of the stonefly genus Zwicknia (Plecoptera: Capniidae)

“…This study contributes to our understanding of the mate‐searching vibrational communication in these insects with only a few pieces of information leaving many questions open. For example, similarly to other duetting insects (e.g., Noh & Henry, 2010; Derlink et al ., 2014; Ge et al ., 2019) the specificity of male preferences for female answer signals may also contribute to reproductive isolation. The intraspecific, interpopulation variation of female preferences and male drumming call characters should be examined in subsequent studies to reveal more details about the evolutionary processes shaping vibrational communication in these species.…”