Papaver rhoeas (corn poppy) is a major, troublesome weed in winter crops. In conventional agriculture, poppy control is essentially achieved through herbicide application. Following intensive use of these substances, resistance has evolved in many poppy populations across its range in Europe. Among the herbicide modes of action concerned by resistance are auxinmimetic herbicides (HRAC group 4/O). Resistance to this mode of action has little been investigated, and its determinants remain largely unknown. Literature data suggests that, while target-site-based resistance exist, non-target-site-based resistance mechanisms may be predominant. Target-site-based resistance to auxinic herbicides is likely oligogenic, while nontarget- site-based resistance is often a quantitative, polygenic trait. Thus, identifying the genes and alleles at the root of resistance to auxinic herbicides in poppy requires being able to scan variation at the genome and/or transcriptome scale. Poppy not being a model species, no genome or transcriptome resources were available for this species. To fill this gap, we established one reference genome and one reference transcriptome for poppy using a sensitive plant for each reference sequence. These resources will be described herein, as well a wholetranscriptome approach (RNASeq) that we implemented to identify candidate resistance genes on the basis of differences in expression patterns between resistant and sensitive plants. This approach will subsequently be extended and complemented by genome-wide association studies aiming at identifying additional genes or polymorphisms associated to resistance to auxinic herbicides. After validation, resistance-associated polymorphisms will be used for massive diagnosis of resistance to auxinic herbicides via high-throughput, molecular diagnosis assays.