Resistance to a nonselective 4-hydroxyphenylpyruvate dioxygenase-inhibiting herbicide via novel reduction-dehydration-glutathione conjugation in Amaranthus tuberculatus.

ABSTRACT: Metabolic resistance to 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides is a threat in controlling waterhemp (Amaranthus tuberculatus) in the USA. We investigated resistance mechanisms to syncarpic acid-3 (SA3), a nonselective, noncommercial HPPD-inhibiting herbicide metabolically robust to Phase I oxidation, in multiple-herbicide-resistant (MHR) waterhemp populations (SIR and NEB) and HPPD inhibitor-sensitive populations (ACR and SEN). Dose-response experiments with SA3 provided ED₅₀ -based resistant : sensitive ratios of at least 18-fold. Metabolism experiments quantifying parent SA3 remaining in excised leaves during a time course indicated MHR populations displayed faster rates of SA3 metabolism compared to HPPD inhibitor-sensitive populations. SA3 metabolit

SUBMITTER: Concepcion JCT 

PROVIDER: S-EPMC9292532 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature