Submitted to: Insect Biochemistry and Molecular Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 7, 2004
Publication Date: November 5, 2004
Citation: Zhu, Y., Snodgrass, G.L., Chen, M. 2004. Enhanced esterase gene expression and activity in a malathion resistant strain of the tarnished plant bug, lygus lineolaris. Insect Biochemistry and Molecular Biology. Interpretive Summary: In this study, we examined esterase gene structure, gene expression levels, and enzymes activities between malathion-susceptible and -resistant strains of the tarnished plant bug. We also investigated how esterase inhibitors suppressed enzyme activities and synergized malathion toxicity to the tarnished plant bug. This study provides information on resistance gene regulation in malathion-resistant strains of the tarnished plant bug. Esterase-mediated metabolic resistance resulted in more than 10-fold higher esterase activity in a resistant strain conferring more than an 11-fold increase in resistance to malathion in a natural population. Increased esterase gene expression levels may be responsible for the resistance development. Two esterase inhibitors exhibited significant suppression to esterase activities, and synergism for malathion. Results from this study will facilitate further studies to investigate regulatory factors for gene overexpression, to develop molecular or biochemical markers for monitoring resistance in field populations, and to provide information for developing pest management strategies.