Cytochrome P450CYP72A219is Involved in Evolution of Metabolic Resistance to Tembotrione inAmaranthus palmeriPopulations

Abstract

SUMMARYEvolution of metabolic herbicide resistance is a major issue for weed management. Few genes and regulatory mechanisms have been identified, particularly in dicotyledonous weed species. We identified putative causal genes and regulatory mechanism for tembotrione-resistance inAmaranthus palmeri.Cytochrome P450 candidate genes were identified through RNA-seq analysis. We validated their functions using heterologous expression inS. cerevisae. Promoters of the candidate P450 genes were analyzed. We performed QTL mapping to identify genomic regions associated with resistance.CYP72A219_4284 deactivated tembotrione. This gene had increased expression in otherA. palmeripopulations resistant to multiple herbicides, including-tembotrione. Resistant plants exhibited polymorphisms in the promoter of CYP72A219_4284. We identified QTLs linked to herbicide resistance, including one on chromosome 4 approximately 3 Mb away from CYP72A219_4284.CYP72A219_4284 is involved in tembotrione resistance inA. palmeri. Increased expression of this gene could be due tocis-regulation in the promoter, as well astrans-regulation from transcription factors. The elucidation of regulatory genes is crucial for developing innovative weed management approaches and target-based novel molecules.