Synergistic effects of combining visual cues and pheromones for the monitoring and management of tarnished plant bug, Lygus lineolaris (Hemiptera:Miridae)

Authors: George, Justin; Reddy, Gadi V.P.

Submitted to: Entomological Society of America, Southwestern and Southeastern Branch
Publication Type: Abstract Only
Publication Acceptance Date: 2/15/2022
Publication Date: N/A
Citation: N/A

Interpretive Summary: The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is a polyphagous, sap-feeder that causes significant economic damage in several field crops, especially cotton (Gossypium hirsutum L.) in the mid-southern United States. Developing monitoring and trapping devices based on visual cues and pheromones will be very useful for making insecticide application decisions and populations dynamics studies. Previous studies have reported the possible role of different ratios of volatile pheromone odorants such as hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal in eliciting low attraction by L. lineolaris under field conditions. In this study, we tested different visual cues (colored sticky cards) and its combination with olfactory cues (odorant blends) to optimize the attraction and capture of L. lineolaris. The red colored sticky cards that were found highly attractive to L. lineolaris adults were then combined with different known L. lineolaris pheromone blends such as Byer blend (4:10:7), Stoneville blend (10:4:2), and Maricopa blend (7:10:4) under field conditions in paired experiments to understand its effectiveness in improving L. lineolaris capture. All these three odorant blends attracted significantly more L. lineolaris than paired control sticky cards. Byer blend attracted and captured significantly higher number of L. lineolaris than the other blends and control after the first week of the experiment. The cumulative number of L. lineolaris captured in the Byer or Maricopa blend containing sticky cards were significantly higher than Stoneville blend during the following six weeks of the experiment. Our results showed that combining the visual cues (red color) with olfactory cues (pheromone blends) significantly increased the capture of L. lineolaris.

Technical Abstract: The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), (Hemiptera: Miridae) is considered the most damaging pest of cotton (Gossypium hirsutum L.) in the mid-southern United States. Previous studies have reported the possible role of different ratios of volatile pheromone odorants such as hexyl butyrate, (E)-2-hexenyl butyrate, and (E)-4-oxo-2-hexenal in eliciting low attraction by L. lineolaris under field conditions. In this study, we tested different visual cues (colored sticky cards) and its combination with olfactory cues (odorant blends) to optimize the attraction and capture of L. lineolaris. The red colored sticky cards that were found highly attractive to L. lineolaris adults were then combined with different known L. lineolaris pheromone blends such as Byer blend (4:10:7), Stoneville blend (10:4:2), and Maricopa blend (7:10:4) under field conditions in paired experiments to understand its effectiveness in improving L. lineolaris capture. All these three odorant blends attracted significantly more L. lineolaris than paired control sticky cards. The three blend treatments and control sticky cards were further tested in a randomized complete block design experiment to identify the best blend that can be effectively used for monitoring L. lineolaris under field conditions. The residual activity of these blends was also tested for six weeks under field conditions. Byer blend attracted and captured significantly higher number of L. lineolaris than the other blends and control after the first week of the experiment. The cumulative number of L. lineolaris captured in the Byer or Maricopa blend containing sticky cards were significantly higher than Stoneville blend during the following six weeks of the experiment. Our results showed that combining the visual cues (red color) with olfactory cues (pheromone blends) significantly increased the capture of L. lineolaris.