Interaction between visual and olfactory stimuli during host-finding by leafhopper,Dalbulus maidis (Homoptera:...

Area of Science:

• Plant-insect interactions
• Chemical ecology
• Behavioral entomology

Background:

• Limited knowledge exists on plant volatile roles in host-finding for Homoptera, Suborder Auchenorrhyncha.
• Understanding olfactory cues is crucial for insect host-finding behavior.

Purpose of the Study:

• To investigate the influence of plant volatiles on the orientation and postcontact behaviors of the leafhopper, Dalbulus maidis.
• To determine the interplay between visual and olfactory stimuli in the host-finding process of D. maidis.

Main Methods:

• Laboratory bioassays were conducted using volatile extracts from maize (preferred host), gamagrass (marginal host), and sorghum (nonhost).
• Leafhopper contacts with green light were quantified under different volatile exposures and compared to a hexane control.
• Postcontact behaviors, including stationary time and movement, were analyzed within the green light boundary.

Main Results:

• Dalbulus maidis showed increased contacts with green light when exposed to maize volatiles compared to hexane.
• Maize volatiles synergistically enhanced leafhopper attraction to green light, indicating a visual-olfactory interaction.
• Postcontact, maize volatiles significantly increased stationary time but did not affect movement parameters.

Conclusions:

• This study provides the first evidence of visual and olfactory stimulus interaction in leafhopper host-finding.
• Plant volatiles mediate postcontact behaviors in leafhoppers beyond feeding, influencing their interaction with potential hosts.