fpls-08-00555 April 8, 2017 Time: 16:50 # 1 ORIGINAL RESEARCH published: 11 April 2017 doi: 10.3389/fpls.2017.00555 Physiological and Molecular Characterization of Hydroxyphenylpyruvate Dioxygenase (HPPD)-inhibitor Resistance in Palmer Amaranth (Amaranthus palmeri S.Wats.) Sridevi Nakka1, Amar S. Godar2, Prashant S. Wani3, Curtis R. Thompson1, Dallas E. Peterson1, Jeroen Roelofs3 and Mithila Jugulam1* 1 Department of Agronomy, Kansas State University, Manhattan, KS, USA, 2 Department of Plant Sciences, University of California, Davis, CA, USA, 3 Division of Biology, Kansas State University, Manhattan, KS, USA Edited by: Herbicides that inhibit hydroxyphenylpyruvate dioxygenase (HPPD) such as mesotrione Rafael De Prado, Universidad de Córdoba, Spain are widely used to control a broad spectrum of weeds in agriculture. Amaranthus Reviewed by: palmeri is an economically troublesome weed throughout the United States. The Pablo Tomás Fernández-Moreno, first case of evolution of resistance to HPPD-inhibiting herbicides in A. palmeri was Universidad de Córdoba, Spain Ricardo Alcántara-de la Cruz, documented in Kansas (KS) and later in Nebraska (NE). The objective of this study was Federal University of Viçosa, Brazil to investigate the mechansim of HPPD-inhibitor (mesotrione) resistance in A. palmeri. *Correspondence: Dose response analysis revealed that this population (KSR) was 10–18 times more Mithila Jugulam resistant than their sensitive counterparts (MSS or KSS). Absorbtion and translocation
[email protected] analysis of [14C] mesotrione suggested that these mechanisms were not involved in Specialty section: the resistance in A. palmeri. Importantly, mesotrione (>90%) was detoxified markedly This article was submitted to Agroecology and Land Use Systems, faster in the resistant populations (KSR and NER), within 24 hours after treatment a section of the journal (HAT) compared to sensitive plants (MSS, KSS, or NER).