Analysis of tarnished plant bug movement using carbon and nitrogen isotopes

Authors: Parys, Katherine; Price, Leslie; Portilla, Maribel; Blackman, Bryce; Roberts, Gregory - Chad; JACKSON, RYAN - Syngenta, Inc; Luttrell, Randall

Submitted to: World Cotton Research Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 5/27/2016
Publication Date: N/A
Citation: N/A

Interpretive Summary: Tarnished plant bugs are the primary pest of cotton in the mid-south of the United States. These insects move into cotton fields from other plants, including a variety of other cultivated crops and wild host plants. Stable isotope analysis has been used in other studies to help determine what types of plants other insects developed on. These insects retain an isotopic signature similar to the plant on which they fed as larvae. Tarnished plant bugs use hundreds of plants as hosts, which utilize two different types of photosynthesis. Insects were collected using sets of 500 sweeps from both crops and weeds throughout the Mississippi Delta from June- December of 2015. Both tarnished plant bug adult and nymphs were subjected to stable isotope analysis. Of the nymphs screened, very few gave off a signal different than the host plant that they were collected from. Higher numbers of adult tarnished plant bugs moved between host plant types. This movement between host plants is a potential point of control for the tarnished plant bug.

Technical Abstract: Tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is the primary pest of cotton across the Midsouth of the United States. Movement into cotton fields occurs during the summer from other host plants, both cultivated and wild. Stable isotope analysis (SIA) has been used in other studies to determine the natal hosts of L. lineolaris adults, as they retain an isotopic signature similar to the host plant that they utilized for nymphal development. Tarnished plant bugs utilize hundreds of species of plants as food, including both C3 and C4 hosts. Collections of L. lineolaris were made using a standard set of 500 sweeps on a variety of both wild and cultivated host plants throughout the Mississippi Delta during 2015, and both nymphs and adults were subjected to SIA. The signal obtained from nymphs matched the signal of dominant host plants at the collection location, while adults lacked the same degree of host fidelity observed in nymphs. These host plant signals provide information that can be used to document movement among host plants and potentially identify alternate targets for L. lineolaris control measure before damage occurs in cotton.