Integrating semiochemicals and trap cropping practices for Lygus lineolaris management in cotton.

Authors: George, Justin; Reddy, Gadi V.P.; HALL, DAVID - Natural Resources Institute Finland (LUKE)

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/27/2023
Publication Date: N/A
Citation: N/A

Interpretive Summary: Tarnished plant bug, Lygus lineolaris, is a major cotton pest around the world. We investigated the synergistic effects of trap color and addition of lures containing blends of pheromone components on catches of L. lineolaris on sticky traps, under field conditions. Different colored sticky cards were tested in cotton fields to determine their efficacy in attracting L. lineolaris. Red-colored sticky cards were more attractive to L. lineolaris adults than white, blue or yellow cards. Red sticky cards combined with blends of three potential pheromone components attracted significantly more L. lineolaris adults than sticky cards without a blend added. Traps baited with a blend of hexyl butyrate, (E)-2-hexenyl butyrate and (E)-4-oxo-2-hexenal in 4:10:7 ratio, respectively, caught a significantly higher number of L. lineolaris than those baited with 10:4:2 or 7:10:4 blends or an unbaited control in the first week of the experiment. Pheromone blend that attracted the most number of L. lineolaris was also tested with different trap colors to confirm there was no unexpected interaction of color and olfactory cues, in order to provide an optimized trap and lure for monitoring L. lineolaris. Our results show that these traps will be very useful in early monitoring of tarnished plant bugs in the field and will help in making pest management decisions. This pheromone blend-red sticky card trap was further tested in combination with trap crops to attract the L. lineolaris to the less expensive mustard trap crop, and can be killed by spraying insecticides. Planting trap crops significantly increases natural enemy populations and enhances biological control of different life stages of many cotton pests. Our preliminary results show that a combination of semiochemicals with trap crops attracts significantly more Lygus to the trap crops and reduces the plant bug damage in nearby rows of cotton.

Technical Abstract: dentifying and optimizing visual and olfactory cues used by tarnished plant bug, Lygus lineolaris, for mate finding and host location are critical in the development of monitoring tools and integrated management practices against this major cotton pest. We investigated the synergistic effects of trap color and addition of lures containing blends of pheromone components on catches of L. lineolaris on sticky traps, under field conditions. Different colored sticky cards were tested in cotton fields to determine their efficacy in attracting L. lineolaris. Red-colored sticky cards were more attractive to L. lineolaris adults than white, blue or yellow cards. Red sticky cards combined with blends of three potential pheromone components attracted significantly more L. lineolaris adults than sticky cards without a blend added. Traps baited with a blend of hexyl butyrate, (E)-2-hexenyl butyrate and (E)-4-oxo-2-hexenal in 4:10:7 ratio, respectively, caught a significantly higher number of L. lineolaris than those baited with 10:4:2 or 7:10:4 blends or an unbaited control in the first week of the experiment. Pheromone blend that attracted the most number of L. lineolaris was also tested with different trap colors to confirm there was no unexpected interaction of color and olfactory cues, in order to provide an optimized trap and lure for monitoring L. lineolaris. This pheromone blend-red sticky card trap was further tested in combination with trap crops to attract the L. lineolaris to the less expensive mustard trap crop, and can be killed by spraying insecticides. Planting trap crops significantly increases natural enemy populations and enhances biological control of different life stages of many cotton pests. Our preliminary results show that a combination of semiochemicals with trap crops attracts significantly more Lygus to the trap crops and reduces the plant bug damage in nearby rows of cotton.